# Long range, high speed Spitfire fighter: the best approach?



## tomo pauk (May 5, 2013)

The Spitfire was one of the best known planes ever, and, especially in the UK, it is still regarded as the best fighter of ww2 by many. However, it was not good in some things: the fuel tankage was modest, even with changes introduced mid-war, and (with Merlin engines, ie. most of the examples produced) it was 'only' as fast as LW opposition, unlike the similarly-engined P-51B/C/D/K. 
So what would be your take: what changes to introduce, in order to push the Merlin Spitfire beyond, say, Ruhr, while gaining some speed (in 20000-35000 ft altitude range, focus being 25-30000 ft) in process? We need the plane to be fielded in May/June 1943 at least.


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## drgondog (May 5, 2013)

Laminar flow wing to reduce profile drag by 30%.

Greater sloped flat glass windscreen to further reduce stagnation Drag (as it did later)

Aft fuselage tank


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## KiwiBiggles (May 5, 2013)

drgondog said:


> Aft fuselage tank



Given the Spitfire's longstanding CoG issues, an aft fuel tank would have been a complete non-starter. In fact, moving the engine forward 18" would have allowed more tankage, and would have improved the CoG range.

And if you then really wanted to retain the Spit's marginal longitudinal stability, I guess you could then chuck in an aft tank.


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## gumbyk (May 5, 2013)

Laminar flow wing
Engine cooling system similar to the mustang
fully faired wheel wells.

Then start looking at increasing fuel tankage.


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## davebender (May 5, 2013)

You can only cram so much internal fuel into that small airframe. Start with a clean sheet of paper just as Messerschmitt did when they designed Me-309 airframe to hold 770 liters of internal fuel, almost twice as much as Me-109. Larger airframe would also be a better fit for RR Griffon engine just as larger Me-309 airframe was a better fit for DB603 engine.


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## Tante Ju (May 5, 2013)

Take a Mark VIII and heck saw. Saw off about 3 feet from each wingtip, and wrap it up in a way you find aesthetically pleasing.

Some duct tape over the undercarriage well wouldn't hurt either.


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## bob44 (May 5, 2013)

Redesign the wings for less drag, carry fuel similar to P51, redesign the cooling scoops similar to P51, clean up the fuselage, if possible add aft fuel tank?


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## dobbie (May 5, 2013)

I think you would have ended up with a different fighter than the Spitfire. As it was designed as an interceptor, there would be far too many necessary changes in order to turn it into an escort type aircraft. However, Id love to see what the result would be! 
If modifying the Spit is the only option, maybe laminar flow wings and as to the fuel tankage, possibly a wet wing? Its either that or stretch the fuselage to incorporate a fuselage tank, either ahead or behind the pilot.


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## gumbyk (May 5, 2013)

I Know! We could call it something different too! Like "Spiteful"


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## davebender (May 5, 2013)

Probably end up with a lemon, tarnishing the otherwise stellar Spitfire record as a lightweight fighter aircraft. Is that what we want?


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## nuuumannn (May 5, 2013)

> Probably end up with a lemon, tarnishing the otherwise stellar Spitfire record as a lightweight fighter aircraft.



Not really, I mean, look at what was actually done with it. The centre fuselage section from Frame 5, the firewall to Frame 19, the diagonal where the tail section joins was the same in every Spitfire/Seafire mark from the V to the Seafire 47, with either a cut down or high back rear fuselage. Any number of mods to engine, wing to which the undercarriage was fitted, and tailplane could be incorporated. Altering the fuse to take increased tankage might be a bit difficult and stretch the "Spitfire" legacy a bit much, hence the Spiteful being renamed. The Mk.21 was going to be renamed because of the vast differences between it and previous marks, but its centre fuse was the same and the name stuck.







This is a Mk.21.


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## wuzak (May 5, 2013)

I think forget the laminar flow wings. Just concentrate on good surface finishes all over, fix the windscreen rake, add fuel somehow - in the wings if possible, in the rear fuselage. The Mk XIV and 21 had longer noses despite having a shorter engine - I presume mire fuel was stuck in the difference?

The opportunity to do more wing tanks was available with the Mk 21 wings. There were small tanks in the leading edges between the fuselage and the cannon bays. Why not outboard the cannons? In early Spits the 4 x 0.303" bays were in teh way, but not for the 21.

Tidy up the radiators. They did use the Meredith effect, and they did have boundary layer splitters. Just needed some work on volumes and input and output areas, plus a flap that was more adjustable (most had 2 positions on the Spits, IIRC).

May not be as fast as a laminar flow wing model, but it would be fast enough and would retain the Spitfire's handling qualities.


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## gumbyk (May 5, 2013)

wuzak said:


> I think forget the laminar flow wings. Just concentrate on good surface finishes all over,


Why wouldn't you use them?

There is a reason laminar flow aerofoils are in popular use. They work.


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## wuzak (May 6, 2013)

gumbyk said:


> Why wouldn't you use them?
> 
> There is a reason laminar flow aerofoils are in popular use. They work.



The Spitfire's wing worked quite well.

The Spiteful's laminar flow wings helped it go faster (it also had different rads), but it wasn't as well liked as the Spitfire.


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## gumbyk (May 6, 2013)

wuzak said:


> The Spitfire's wing worked quite well.
> 
> The Spiteful's laminar flow wings helped it go faster (it also had different rads), but it wasn't as well liked as the Spitfire.



It was the low thickness to chord ratio that helped it. now, keep that, and the plan-form, but introduce a laminar aerofoil section, and IMO you'd have a better wing.
Or, the ability to increase wing thickness, and actually be able to fit things like wing cannons into the wings, without having the bulges.


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## Aozora (May 6, 2013)

gumbyk said:


> Why wouldn't you use them?
> 
> There is a reason laminar flow aerofoils are in popular use. They work.



The laminar flow wings designed for the Spiteful/Seafang were a pig to get right, with lots of airflow problems around the ailerons, and the bugs were never really ironed out because by 1945 jet aircraft promised better performance. It may well be that successful laminar flow wings could have been designed for the Spitfire had Supermarine consulted with NAA and NACA, but that's pure speculation.


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## Jabberwocky (May 6, 2013)

All sorts of stuff.

Minor changes:

1. Fully enclosed wheel wells (tested in the Mk III)
2. Retractable tail wheel (happened in the Mk VIII)
3. Fully flush riveted construction (happened in the Mk VIII)
4. Leading edge fuel tanks (happened in the Mk VIII)
5. Larger forward fuel tanks (happened in the Mk VIII)
6. Fit Hispano Mk V cannon (happened in the Mk 21)
7. Fit inboard .50 cal (happened in the Mk IXe)

Moderately easy changes:

7. Re-angle front windscreen and fit curved 'Speed Spitfire' window fairing (tested on the Mk XIV, showed 8 mph improvement in speed)
8. Fit 29 imp gal rear fuselage tank (happened in the Mk V)
9. Re-design the aircraft to use US-style aircraft fasteners (much lower panel gaps on US fighters)
10. Re-profile the nose skinning to Griffon-engine style 1 piece skin 
11. Lengthen the nose profile slightly to add more fuel and aid the CoG issue

Difficult changes:

12. Reprofile the radiators to take better advantage of boundary layer and Meredith effect
13. Partially laminar flow wing


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## parsifal (May 6, 2013)

what are laminar flow wings?

Range of the Spitfire did increase significantly with the Seafire 47 and a few other subtypes


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## Jabberwocky (May 6, 2013)

The ultimate LR armed Spitfire would have been the Mk XVIII

This was a Mk XIV with some strucutral reinforcements and 188 gallons of internal fuel. That's 221% of what the Mk I through IX had. 

Of course, the Mk XVIII also weighed more empty than the Spitfire Mk I did fully loaded.


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## OldSkeptic (May 6, 2013)

KiwiBiggles said:


> Given the Spitfire's longstanding CoG issues, an aft fuel tank would have been a complete non-starter. In fact, moving the engine forward 18" would have allowed more tankage, and would have improved the CoG range.
> 
> And if you then really wanted to retain the Spit's marginal longitudinal stability, I guess you could then chuck in an aft tank.



Those CoG issues were largely sorted out in mid-late 41. Firstly by a temporary expedient of bob weights added to the elevator control line, later by redesigned elevator horns.
The CoG became even less of an issue with the 60 series engines (being longer and heavier) and of course even more so the Griffon.

With a rear tank(s) (actually fitted to late model IX, XVI and XIV Spits) of ranging between 66 and 75 gallons (imperial) the Spit was unstable, but so was the Mustang with its rear tank full.
The key was to burn that off first on climbs and cruise. Then it became a normal Spit again.

My calculations, based on a Mk VIII, with the leading edge tanks, showed a combat radius of 500 miles (= Berlin) was quite possible.

Jeffery Quill (the great Spit test pilot) did an example flight, which he documents in his book. Mk IX, rear tank, 90 gallon drop tank and a bob weight on the elevator control line. Flew to the North of Scotland and back with no issues (same as a Berlin round trip).

In fact you could squeeze a little more of out the Spit VIII for long range missions by, removing the 4 x .303 guns and adding another 26gallons (13 in each wing) in additional leading edge tanks.
The USAAF also flew 2 Spits across the Atlantic with modified Spits, with Mustang like double drop tanks in each wing.

There was no technical issue with a LR Spit (as I have shown before here), not a Mustang though as that was was really a VLR plane.

The range issue is about, after you have a stable aircraft and you have dropped your external tanks, how much fuel do you have left for combat and returning?
In my calculations I allowed a 15min combat time and cruise to Berlin and back.
Obviously shorter ranges would have allowed longer combat time, though ammo would have been the key issue then.

Link to late model Mk IX/XVI models 66 (imperial) gallon rear tanks: http://www.spitfireperformance.com/spitfire9-fuelsystem-lr.jpg


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## wuzak (May 6, 2013)

Jabberwocky said:


> The ultimate LR armed Spitfire would have been the Mk XVIII
> 
> This was a Mk XIV with some strucutral reinforcements and 188 gallons of internal fuel. That's 221% of what the Mk I through IX had.
> 
> Of course, the Mk XVIII also weighed more empty than the Spitfire Mk I did fully loaded.



What was the range of the XVIII?

The XIV and XVIII had engines angled to give the pilot a better view over the nose. Because of that they had to use a smaller diameter prop, and thus went for 5 blades. I wonder how much of an effect this had on propulsive efficiency? Also, I believe the prop tips would be supersonic near the aircraft's top speed.

For the 21 and later the cockpit was raised slightly and the engine straightened. The landing gear was also longer, I believe. So they were abl;e to use a bigger prop again.


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## OldSkeptic (May 6, 2013)

Jabberwocky said:


> All sorts of stuff.
> 
> Minor changes:
> 
> ...



Pretty much bang on. except the wing.
The Spit wing very, very good and had lower drag than the Mustang's in several flight regimes (overall the Spit was better on the climb and worse on the dive, roughly similar on level flight(ie a low Cl), better at high speeds with better mach induced drag (where drag stops being linear with the square of the speed, and become exponential).

Therefore the lower speed for the same power came down to radiator drag and detail drag.

Small details matter. The 20mm cannon Mk Vs were 5mph slower than the Mk Vs with 8x0.303.
The bulletproof flat windscreen cost (with a rear mirror) about 10mph (ditto the Mosquito fighters, fighter/bombers, vs recon and bombers).
It got worse with speed as it had a critical mach limit of only about 0.6 (and a bit from memory), therefore the windscreen drag got worse at high speeds.

Radiator drag. The Spit, like the Me-109 used the first versions of utilising the Meridith effect to reduce radiator drag. The Mustang was a generation ahead.
It's placement was far better, being in the fuselage meant less turbulent air and thus better flow control and cooling efficiency. And the design was better, with variable shuttering vs the simple limited settings for the Spit and 109.
Yes the Mustang still had some net radiator drag, but it was very low.

Even one of the designers of the Mustang discounted the wing (which Supermarine found out when it made its own 'laminar' flow wing) as being the reason for its speed. Wind tunnel tests confirm this.

If you take, on similar powers, a 30mph difference in speed (yes it varied a bit for model to model and configuration to configuration, that's a rough average) then 50% was from radiator efficiency, the other 50% was details. I'd take 25mph as a gap to aim for, because the Mustang would also have lost 5mph with similar cannons.

The prototype Spit Mk III, with better radiators and lots of all those details cleaned up was rated for about 400mph compared to 375 for a similarly powered normal Spit. That's that magic 25mph region again.

Supermarine actually proposed moving the radiators to the same location as in the Mustang, and estimated (for a 60 series engine) 430mph. MAP rejected it due to production disruption issues and then came along the Griffon.

So they could have done it. If RR hadn't been able to keep increasing Merlin power and thing bringing on the Griffon then they would probably have been forced to. But they took the easy way of more power being available as it was easier to re-engine the Spit (a wonderful thing about its design) than do other changes.


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## nuuumannn (May 6, 2013)

Yep, Old Skeptic, this makes an interesting what-if, because so much was and could be done with the Spitfire, but I guess there was no need for such a thing from 1943 on (and being anticipated earlier), because of the Mustang - and the fact the British had no requirement for a long range escort, but that's another thread entirely...


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## stona (May 6, 2013)

bob44 said:


> Redesign the wings for less drag, carry fuel similar to P51, redesign the cooling scoops similar to P51, clean up the fuselage, if possible add aft fuel tank?



The Spitfire is to a large extent its wing. It is a very complicated shape indeed.

Redesign the wing and you don't have a Spitfire. The truth is that they went about as far as they could with the Spitfire at the time, you won't be able to achieve anything that wasn't done historically without producing another aeroplane.

How would you clean up the fuselage? It is the shape it is for complicated aerodynamic reasons, particularly the very large wing root fillet (look at a picture of an uncamouflaged Spitfire if you can). Later Marks were flush riveted throughout. There's only so much you can do to the finish of an aircraft in high volume war time production and much of that was done.

Laminar flow wing ? Show me a true laminar flow wing on an aircraft designed in the 1940s,never mind the 1930s like the Spitfire.

Cheers

Steve


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## davebender (May 6, 2013)

Mustang was a British fighter aircraft and it was in service by 1942. Isn't that a better starting point for a long range British fighter aircraft?


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## tomo pauk (May 6, 2013)

Well, the thread is about it 



Jabberwocky said:


> All sorts of stuff.
> 
> Minor changes:
> 
> ...



Agreed pretty much, though the laminar flow wing might not be necessary if the boundary layer (above radiator intakes) is better controlled, and the wheel well covers are installed. The Hispano V is too late for deadline (mid 1943)
The engine should be maybe the Merlin 70 - the Spit VIII IX were making 416 mph @ 27,500 ft with it, vs. 404 mph @ 21,000' ft for the Merlin 66 engined sub-versions. The reduced drag from above-mentioned items might add further 10 mph.


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## drgondog (May 6, 2013)

Simple boundary conditions - Spitfire IX (or VIII) to approximate Mustang LR capability

1. Decrease Profile drag by ~40% *accompanied with *a.) slighly less internal fuel, *and* b.) install wing pyons and plumbing to replenish additional fuselage tanks, *or* increase internal fuel approximately to 120% Mustang and match external fuel capability to attach 108 gallon tanks and plumbing.

2. The Wing, despite low inherent Induced drag due an elliptical wing (higher theoretical oswald efficiency), must dramatically enable the most improvement to the Profile drag of the Wing as the wing is by far the biggest contributor to Drag.

3.) The biggest contributors to the Total Drag of the Spit, in cruise condition, in order
Wing Profile drag due to airfoil type and aspect ratio, then the Parasite Drag, including surface roughness including grainy camo paint and including gaps for wheel and flap/aileron hinges
Fuselage Parasite Drag including canopy
Tail surfaces Parasite Drag including roughness
Engine, Radiator, exhaust stacks Parasite Drag
Appendages (masts, armament, tail wheel) Parasite Drag
Induced Drag
Compressibility Drag (V~ >55% M)

From memory the Wing Drag Alone including Profile Drag plus all the components of Parasite Drag of the Wing are ~50% of the Total Profile Drag/Parasite Drag of the airframe.

I would have to do the calcs to be more precise but IIRC the Cdo of the Spit IX is approx .0023.

Spit Induced Drag was inherently low compared to Mustang so all the focus should be on the Wing, and specifically on the wing section to reduce Profile Drag and still maintain high CL

The Mustang has an incredible CL/CD ratio>14:1 where CL=CD at V= best cruise.

If "All that could be done was Done" on the airfoil itself there are very few areas of investigation that will drive 40% out of CDo or even close. I speculate that stripping 20mm and replacing with .50 cal, closing wheel well, surface prep at factory to fill and sand (like Mustang), polishing wind surface, would take 3+% Parasite drag off the airframe and increase top speed 10-15mph at top speed - but stiil not match Total Drag of the Mustang.

Leaving you with necessity of driving internal fuel supply to exceed the Mustang AFTER you did everything else above except improve the wing airfoil...



At High Speed/High altitude Compressibility Drag increases dramatically for a Spit in the .84-.86 range.


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## OldSkeptic (May 6, 2013)

tomo pauk said:


> Well, the thread is about it
> Agreed pretty much, though the laminar flow wing might not be necessary if the boundary layer (above radiator intakes) is better controlled, and the wheel well covers are installed. The Hispano V is too late for deadline (mid 1943)
> The engine should be maybe the Merlin 70 - the Spit VIII IX were making 416 mph @ 27,500 ft with it, vs. 404 mph @ 21,000' ft for the Merlin 66 engined sub-versions. The reduced drag from above-mentioned items might add further 10 mph.



The wing position for the radiator was about the worst pl;ace you put it. It not only had issues of turbulence in the rad intake affecting radiator efficiency (and angle of attack issues as well), it also affected wing efficiency too.

Supermarine stuck with the wing position for the Spiteful, my god did they work at it to try and get comparable rad efficiency to the Mustang. They probably pulled it off in he end (just), but it would have been a lot easier to got a for a fuselage mount right from the beginning.

What would have helped was a bit further forward in the wing design, into clearer air as per the Spit Mk III, that would have allowed a more efficient design to be employed and thus cutting rad drag.

Basically you wanted the radiator to be inset into the body of the plane (leading edge was another alternative to the fuselage) and be deep, not hanging off the outside of the wing.
I think, from memory again, Hawker with one of the Tempest designs had a deep leading edge radiator and that they claimed zero net drag from it (the Mustang still had some positive drag, just less than anything else).

Amazing the significant impact of small things at the leading parts of the aircraft. When they were desperate for more low level speed for use against the V1, they found that things like chipped paint and poor filling (and so on) could have 5-15mph speed impacts. Significant improvements were often made just by cleaning up the plane.

That was another advantage of the Mustang, Art Chester (an unsung hero). Though not a formally taught engineer, his experience in flying and building racing aircraft gave him great practical knowledge of the combined drag impacts of very small design elements. Schued put him in charge of the power plant design group (am inspired decision) and all that experience paid off with a very smooth front end with meticulous attention to drag inducing details. That plus the radiator were almost certainly responsible for the speed difference.

What the 'laminar' flow (it wasn't) wing did though was to provide a good critical mach limit, despite being fairly thick (enough for both fuel and guns), due to its pressure distribution.
The P-38 showed the problem of having a fast aircraft with a low mach limit, so all the low drag work on the Mustang would have been useless if its mach limit was not high enough for combat.
And it was good, not as high as a Spit, but as high or higher than the German fighters and that was what counted.


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## tomo pauk (May 6, 2013)

Bill, wouldn't the addition of 2 wing racks be a more draggy thing than the existing single attachment point (capable to hold 204 USG drop tank)?


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## drgondog (May 6, 2013)

Yes - but a 200 gallon tank on a Spit is a monster and you still have to get internal fuel above 300 to reasonaly match a 51's range.


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## gumbyk (May 6, 2013)

Aozora said:


> The laminar flow wings designed for the Spiteful/Seafang were a pig to get right, with lots of airflow problems around the ailerons, and the bugs were never really ironed out because by 1945 jet aircraft promised better performance. It may well be that successful laminar flow wings could have been designed for the Spitfire had Supermarine consulted with NAA and NACA, but that's pure speculation.



That's not a fault with laminar flow wings, that's a fault with the designers.


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## OldSkeptic (May 6, 2013)

drgondog said:


> Yes - but a 200 gallon tank on a Spit is a monster and you still have to get internal fuel above 300 to reasonaly match a 51's range.



That's right. best, absolute best you could achieve would be about 2/3rds of the P-51. Still very useful in '43.


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## tomo pauk (May 7, 2013)

+1 on that. 450+ miles of combat radius should provide problems for LW defenders.



drgondog said:


> Yes - but a 200 gallon tank on a Spit is a monster and you still have to get internal fuel above 300 to reasonaly match a 51's range.



It was the monster that worked 
I was not trying to get the Spitire making 700 miles of combat radius, but some 500, ie. 'beyond Ruhr', per post #1 here. If we arrive to laminar flow wing, then also the U/C gear retracting can be changed, so the gear well is located in front of the main/front spar - that would leave the space between spars for fuel tanks. 
Hmm, wonder if the original Spitfire's wing was bale to be reworked for such U/C retracting.

Question for the Spitfire experts: could you please share details about the fuel tank located under the pilot, as found in (early?) PR Spitfires? Was it protected/self-sealing?


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## wuzak (May 7, 2013)

tomo pauk said:


> Hmm, wonder if the original Spitfire's wing was bale to be reworked for such U/C retracting.



Don't know if the original wing was strong enough to do that. More to the point, the structure would probably need totally redesigning.

Supermarine had the opportunity with the Mk 21 wing - which wasn't laminar flow. I think it had the saem profiles as the original, but had a slightly different plan form.

The 21 had the fully enclosed landing gear (outward retracting still) amd was much stronger. I wonder if there weren't so many interruptions (ie interim models, such as the IX, XII XIV) if Smith could have got the new wing onto production aircraft sooner?


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## tomo pauk (May 7, 2013)

> Don't know if the original wing was strong enough to do that. More to the point, the structure would probably need totally redesigning.



Fair enough; maybe it would be less of the task than making a whole new wing?

Another random thoughts:
-coolant and oil radiators in the 'beard 'position, like P-40F, Lanc or Beau, should've made boundary layer induction into those a non-issue? (less drag) Intercooler radiator remains in the place for now.
-hig-alt Merlin 70 + clipped wings - less drag (hopefully), better roll rate, but also less lift - wonder how such a plane would've behaved (speed and RoC wise) between 25-30000 ft?
-leading edge radiators, the British introduced those in a number of planes. The fuel can go where the radiators were 'eating into' wings.

Comments?

added: I've dug out the 'Spitfire - History' book; an interesting tidbit might be this: the Spit V was tested in August of 1942, with 170 IG blister tank and 29IG rear tank. Cruising at 15000 ft, the 'still air range' was 1625 miles. The fuel from blister tank was used for climb and initial part of level flight, then use the rear tank (drop the empty blister tank), then switch to main tank(s). Total fuel load 284 imp gals. Corrected (for fuel used for take off and landing?) range was 1550 miles. 
my comment: Spitfire VIII should add further 35 IG on this, while the 'torpedo' drop tank of 170 IG cuts drag to the level of the 90 IG blister tank. All available in early 1943...


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## OldSkeptic (May 8, 2013)

tomo pauk said:


> +1 on that. 450+ miles of combat radius should provide problems for LW defenders.
> 
> 
> 
> ...



Modified Mk VIII with a 66 (imperial) gallon rear tank and a 90 gallon (or maybe just a 45) drop tank will do 500 mile combat radius.

All consumption numbers taken from Spit VIII pilot notes:

*SpitFire VIII Long Range	*

Mission Range 500 
Combat Time mins 15 
Min Rear Tank Level - 

Spit VIII Capacities (UK Gals)	
Front Tanks 96 
Wings 26 
Rear Tank 66 
Drop Tank(s) 90 
Total Fuel 278 

*Combat Range Calculation	*

T/O Climb Fuel Use	
Main Fuel - 
Rear 26 
Drop - 
Total 26 

Cruise to Target Fuel Used 
Main Fuel - 
Rear 40 
Drop 37 
Total 77 

Cruise to Target Range (Miles) 
Main Fuel - 
Rear 260 
Drop 240 
Total 500 

Combat (15 mins) Fuel Use	
Main Fuel 34 
Total 34 

Return Fuel Left	
Main Fuel Wing 88 
Rear Tank - 
Total 88 
Left 19 
Reserve	10.2%

Return Range miles	
Main Fuel Wing 640 
Rear Tank - 
Total 640 
Reserve Range 140 
% Reserve Range	21.8%



*Notes:*
All cruise speeds at most economical, 20,000ft at 220mph.
Rear tank emptied first.
When going to target (meeting bombers at some specified point and escorting) the spare capacity in the 90 gallon drop tank allows faster cruise speeds for all or parts of the journey.
External tanks dropped before combat.
Moderate reserve fuel for returning, for periods of faster speeds, otherwise at most economical cruise.
Extra (up to) 26 gallons possible if .303 guns removed and additional leading edge tanks added, though they would impact roll rate.
15 mins combat would more than exhaust ammunition, but allows for climbing back to optimum height and fast disengagement.
Combat fuel allowance taken from pilots notes.
Careful tactics needed so that not all escorts run out of fuel/ammo too fast at the same time leaving bombers vulnerable.
Combat with drop tanks against twin engined Luftwaffe planes (110s and JU-88s) acceptable. Not acceptable for 109s or 190s (obviously).

Other thoughts
Merlin 70 (ie HF version) may be more appropriate than Merlin 66, as it allows higher altitude cruise performance, figures based on LF (Merlin 66) version.
Climbs close to bomber rendezvous (especially for the high cover squadrons) can be done on the drop tank, which has a fair reserve). 

If Spit IX used, then leading edge wing tanks need to be added ... obviously.

Pilots need thermal underwear .... and a large bottle....


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## Jabberwocky (May 8, 2013)

tomo pauk said:


> Fair enough; maybe it would be less of the task than making a whole new wing?
> 
> Another random thoughts:
> -coolant and oil radiators in the 'beard 'position, like P-40F, Lanc or Beau, should've made boundary layer induction into those a non-issue? (less drag) Intercooler radiator remains in the place for now.



Chin radiators were probably marginally less efficient that the Spitfire's existing radiator set up. Cooling drag is slightly higher overall, and then you have the issues of increased frontal area and, crucially for the Spitfire, nose heaviness.



> -hig-alt Merlin 70 + clipped wings - less drag (hopefully), better roll rate, but also less lift - wonder how such a plane would've behaved (speed and RoC wise) between 25-30000 ft?



The clipped wings on the Spitfires actually increased drag at high altitudes, due to much more turbulent wing vorticies and induced drag.

Plus, they have less than desirable effects on climb rate, turn and handling above 20,000 ft.



> -leading edge radiators, the British introduced those in a number of planes. The fuel can go where the radiators were 'eating into' wings.



LE radiators were slightly more efficient than either the chin or embeded wing radiators in terms of drag, but only marginally so. Napier put them somewhere between 4.5 and 6.5% better in terms of overall drag.


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## vinnye (May 8, 2013)

Didn't the Hurricane have a central radiator scoop?
I would have thought that the designers could have had a look and see how to do so on the Spitfire quite early in its development?


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## Aozora (May 8, 2013)

gumbyk said:


> That's not a fault with laminar flow wings, that's a fault with the designers.


 
And I didn't make the point by saying Supermarine should have/could have worked with NAA and NACA?


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## wuzak (May 8, 2013)

Where did PR Spits keep all their fuel?

IIRC they had full width leading edge tanks. Is there some what to use them and add 2 cannon, and 2 0.50s or another 2 20mms?


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## tomo pauk (May 8, 2013)

Jabberwocky said:


> Chin radiators were probably marginally less efficient that the Spitfire's existing radiator set up. Cooling drag is slightly higher overall, and then you have the issues of increased frontal area and, crucially for the Spitfire, nose heaviness.



Not even the greatest Spitfire fans would say that plane's radiators were that _good_. As for cooling drag being slightly higher overall (for frontal/beard raditor) - why would that be the case; ditto for frontal area? The oil tank would need to be removed, probably under pilot, so that should balance things somewhat. 



> The clipped wings on the Spitfires actually increased drag at high altitudes, due to much more turbulent wing vorticies and induced drag.
> 
> Plus, they have less than desirable effects on climb rate, turn and handling above 20,000 ft.



Guess you're right about it.



> LE radiators were slightly more efficient than either the chin or embeded wing radiators in terms of drag, but only marginally so. Napier put them somewhere between 4.5 and 6.5% better in terms of overall drag.



Okay - we could see some 5% increase in speed then - a 20 mph plus?




wuzak said:


> Where did PR Spits keep all their fuel?
> 
> IIRC they had full width leading edge tanks. Is there some what to use them and add 2 cannon, and 2 0.50s or another 2 20mms?



Use the PR wings as the base, while making room for the gun barrels? So instead of 2 x 66 IG, we have maybe 2 x 45-50 IG?
Were the PR wing fuel tanks protected/self-sealing?


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## Jabberwocky (May 9, 2013)

tomo pauk said:


> Not even the greatest Spitfire fans would say that plane's radiators were that _good_. As for cooling drag being slightly higher overall (for frontal/beard raditor) - why would that be the case; ditto for frontal area? The oil tank would need to be removed, probably under pilot, so that should balance things somewhat.



I agree that the Spitfire's radiators weren't that good, but the RAE reported that the Mk Vb's powerplant drag was 18.2% of the airframe's total drag, while the Hawker Typhoon's powerplant drag was 27.1% and the Tempest's powerplant drag was 24.2% of total.

To me, that suggests either one of two things: the Spitfire's radiator set up was more efficient than on the Hawker aircraft, OR, that the drag on the Hawker aircrafts' airframe drag was much lower. Given that a Mk XII with 1820 hp (Griffon IV at sea-level) was 3-4mph faster than a Hawker Typhoon with a 2020 hp (Sabre II at sea level), I'd plumb for the first case rather than the latter. 



> Okay - we could see some 5% increase in speed then - a 20 mph plus?



Not really. As engine/cooling drag is only about 10-25% of total airframe drag. Rolls-Royce estimated that if the Mk IX's radiators were completely reworked and operating at a theoretical minimal drag (which, in reality, was impossible to obtain), then the speed of the aircraft would be improved by 13 mph, which is about 3.2%.

If you want to know what a basic clean up of an airframe, then this Typhoon IB Performance Data makes fascinating reading.

Basic Typhoon IA achieved 405 mph in late 1941 tests. Tests of Gloster production aircraft in May/June 1942 showed top speeds had dropped to 380-385 mph due to addition of the four cannon, the external rudder mass balances and various other protrouberances. 

A quick clean up of production aircraft in July 1942, and top speeds were back up to about 392-398 mph. Further clean ups over the rest of the year and production aircraft were back at about 402-405 mph. A few more detail improvements in 1943 and production aircraft were hitting 413-417 mph by the end of the year, which was faster than the Browning armed prototype.

Detail improvements to the airframe meant that the aircraft gained about 35 mph with no increase in horsepower. Makes the effort of completely reworking the cooling system seem maybe a little much.


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## wuzak (May 9, 2013)

Jabberwocky said:


> Basic Typhoon IA achieved 405 mph in late 1941 tests. Tests of Gloster production aircraft in May/June 1942 showed top speeds had dropped to 380-385 mph due to addition of the four cannon, the external rudder mass balances and various other protrouberances.
> 
> A quick clean up of production aircraft in July 1942, and top speeds were back up to about 392-398 mph. Further clean ups over the rest of the year and production aircraft were back at about 402-405 mph. A few more detail improvements in 1943 and production aircraft were hitting 413-417 mph by the end of the year, which was faster than the Browning armed prototype.
> 
> Detail improvements to the airframe meant that the aircraft gained about 35 mph with no increase in horsepower. Makes the effort of completely reworking the cooling system seem maybe a little much.



There would have been some power improvement in that period. Possibly 10-20% improvement.


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## Jabberwocky (May 9, 2013)

wuzak said:


> There would have been some power improvement in that period. Possibly 10-20% improvement.


 
Sabre II wasn't re-rated for +9lbs until after July 1943.

The flight trials show only a minimal improvement in top speed (+2 mph), although below critical altitude there was up to 15 mph benefit.

Most of the gains from cleaning up were made before the engine was cleared for higher boost. The May 1943 tests show 410-414 mph top speed, the August 1943 tests show 417 mph, on a repaired aircraft, so its debatable whether its Sabre would have been re-rated or not.


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## tomo pauk (May 10, 2013)

Jabberwocky said:


> I agree that the Spitfire's radiators weren't that good, but the RAE reported that the Mk Vb's powerplant drag was 18.2% of the airframe's total drag, while the Hawker Typhoon's powerplant drag was 27.1% and the Tempest's powerplant drag was 24.2% of total.



Got me puzzled a little bit here - the Spitfire IX three radiators' system was 'accused' to require 400 HP to overcome it's own drag, per 'Aeroplane' article posted on this forum (I cannot post the lik on this instant), vs. P-51 system that required 50 HP to do the same. Guess we could use a thread dedicated to clarify the powerplant/cooling drag for ww2 airplanes.
The Hawker's duo was using an almost under-slung radiator system, unlike the more 'embedded' one we can find at Miles M20, or P-40F.



> To me, that suggests either one of two things: the Spitfire's radiator set up was more efficient than on the Hawker aircraft, OR, that the drag on the Hawker aircrafts' airframe drag was much lower. Given that a Mk XII with 1820 hp (Griffon IV at sea-level) was 3-4mph faster than a Hawker Typhoon with a 2020 hp (Sabre II at sea level), I'd plumb for the first case rather than the latter.



Do you compare high speeds at sea level, or at 2nd gear FTH?
The Typhoon have had the greater Cd0 (0.0238 ) and wetted area (12.5% +), vs. Spit Vc (Cd0=0.0218; the Mk.XII was in the ballpark), so it's total drag (as a force) was almost 15% greater.



> Not really. As engine/cooling drag is only about 10-25% of total airframe drag. Rolls-Royce estimated that if the Mk IX's radiators were completely reworked and operating at a theoretical minimal drag (which, in reality, was impossible to obtain), then the speed of the aircraft would be improved by 13 mph, which is about 3.2%.



Acknowledged - more material for the new thread 



> If you want to know what a basic clean up of an airframe, then this Typhoon IB Performance Data makes fascinating reading.
> Basic Typhoon IA achieved 405 mph in late 1941 tests. Tests of Gloster production aircraft in May/June 1942 showed top speeds had dropped to 380-385 mph due to addition of the four cannon, the external rudder mass balances and various other protrouberances.
> 
> A quick clean up of production aircraft in July 1942, and top speeds were back up to about 392-398 mph. Further clean ups over the rest of the year and production aircraft were back at about 402-405 mph. A few more detail improvements in 1943 and production aircraft were hitting 413-417 mph by the end of the year, which was faster than the Browning armed prototype.



Thanks, I've read the most of the stuff there, but it won't hurt to read it again.



> Detail improvements to the airframe meant that the aircraft gained about 35 mph with no increase in horsepower. Makes the effort of completely reworking the cooling system seem maybe a little much.



There was no such thing (35mph improvement) for Spitfires, eg. different 'series' of the Mk.IX on same engine and it's power setting.


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## nincomp (May 10, 2013)

OldSkeptic said:


> That's right. best, absolute best you could achieve would be about 2/3rds of the P-51. Still very useful in '43.



Interesting. Was this due to some characteristic of the fuselage, or would it have taken too much time and effort to do a complete "clean-up?" Other issues?

On the other hand, did I completely miss the point because you are talking about range instead of speed?

edited to add: Rats, I am a moron. I got confused and thought that the quoted comment was about speed.
I hate it when I do that.


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## OldSkeptic (May 10, 2013)

nincomp said:


> Interesting. Was this due to some characteristic of the fuselage, or would it have taken too much time and effort to do a complete "clean-up?" Other issues?
> 
> On the other hand, did I completely miss the point because you are talking about range instead of speed?
> 
> ...



Not enough room in the wings for tanks basically. The Mustang had 150 (imperial) gallons with a 71 gallon rear tank giving a total of 221 gallons.
The Spit VIII had 96 in the front tanks and 26 in the leading edge tanks, giving a total of 122. With a rear 66 gallon tank that makes 188 gallons in total.

There was no room in the wings for extra tanks with guns basically.

You might have been able to put in another 26 gallons in the outer leading edge if you deleted the 0.303 guns. Bringing the total to 214. But that is a maybe.

Taking the proven numbers the Spit VIII has 85% of the internal tankage. 
But The mustang has a higher most economical speed 253mph vs 220mph and it used a little less fuel per hour (around 4%-5%, depending on model and assumptions) .
Still a little bit better even with the 2x62.5 gal drop tanks vs the single 90 gal Spit drop tank, though the gap closed (maybe 2% to 3% better).

Adjusting for all that you get the LR Spit range being around 68% to 70% of the Mustang, depending on plane models (P-51C or D, Spit HF VIII or LF VIII, a few assumptions, etc).

So internal fuel capacity and parasitic drag basically.


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## wuzak (May 10, 2013)

OldSkeptic said:


> Not enough room in the wings for tanks basically. The Mustang had 150 (imperial) gallons with a 71 gallon rear tank giving a total of 221 gallons.
> The Spit VIII had 96 in the front tanks and 26 in the leading edge tanks, giving a total of 122. With a rear 66 gallon tank that makes 188 gallons in total.
> 
> There was no room in the wings for extra tanks with guns basically.
> ...



The Spitfire PR.XIX had (from memory) 266 UKG. That was with full length leading edge tanks, but no guns. Would it be possible to put access tubes through this L/E tank to enable 2 x 20mm + 2 x 0.50" or 4 x 20mm? How much capacity would that lose?

Alos, when talking about US and British aircraft it would probably be best to specify which gallon is being used - the UKG is about 20% larger than the USG. Or better yet, talk litres.


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## OldSkeptic (May 11, 2013)

wuzak said:


> The Spitfire PR.XIX had (from memory) 266 UKG. That was with full length leading edge tanks, but no guns. Would it be possible to put access tubes through this L/E tank to enable 2 x 20mm + 2 x 0.50" or 4 x 20mm? How much capacity would that lose?
> 
> Alos, when talking about US and British aircraft it would probably be best to specify which gallon is being used - the UKG is about 20% larger than the USG. Or better yet, talk litres.



I did, just used the term 'imperial' gallons.
The PR Spits had 66 gallons in each wing on th leading edge. Some later models had additional 20 gals in each wing (such as the XiX). Bit of course no weapons.

But I might be a little conservative here, just using the inboard 13 gallon leading edge tanks of the Mk VII and Mk VII. 
Looking at the 66 gallon design, of you removed the 4-.303s then another 13 gallons in each wing seems possible
Plus reading all the things they tried for the early PR spits, there is repeated mention of 20 or even 30 gallon tanks being placed under the pilot's seat.

If you add those in you get (all gallons are UK ones):
Fronts tanks: 96 gallons
Wing tanks inner: 13 gallons each (26 in total).
Wing tanks outer: 13 gallons each (26 in total).
Under seat tank: 20 galls
Rear tank: 66 gals.


Total: 234 gallons

Now you would assume than and under the seat tank would not affect CoG much, so you don't have to run it down at first and can retain it for the return flight. 
And that you can live with the poorer roll caused by the outer leading edge tanks being full (PR pilots did after all), so you can again retain them full for returning.

All that pushes your maximum combat escort radius to 700 miles, using the same assumptions I used before, not that far off a Mustang (about 85% actually).


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## tomo pauk (May 11, 2013)

wuzak said:


> The Spitfire PR.XIX had (from memory) 266 UKG. That was with full length leading edge tanks, but no guns. Would it be possible to put access tubes through this L/E tank to enable 2 x 20mm + 2 x 0.50" or 4 x 20mm? How much capacity would that lose?
> ...



I've posted this some time ago. The red 'ovals' and trapeze point to the possible places for fuel tanks. The '?' marked place - anybody knows what was there, was it possible to use it as a place for the fuel tank? Were the LE fuel tanks in the PR spitfires protected/self-sealing?


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## OldSkeptic (May 11, 2013)

Even in the PR Spits with an extra 20 gal tank in the wing had them more inboard than that (basically where the cannons are).

Remember that far out the Spit's wing is getting very, very thin, especially behind the leading edge, so there is not much room anyway.
Debatable whether or not there is more room than in the leading edge if you dump the 0.303s. Andd at least you know there will be no structural issues using the edge.

Look at my calcs, if you can manage an extra 13 (UK) gals in the leading edges giving 4 x 13 =52 gals.
That plus the front tanks (VIII size) of 96 gals, plus a rear 66 gal then you have 214 gals.

That's not a bad start, if you can also squeeze in another 20 gals under the pilots seat that's 234, which is more than the P-51.

26 wings, plus 96 front, plus 66 rear, gives 500 miles combat radius.
52 wings, plus 96 front, plus 66 rear, gives 600 miles combat radius.
Add another 20 gals then you get 700 mile combat radius.

Remember at cruise you are getting over 6.5 air miles per gallon (the exact amount depending on whether the drop tank is on or not).


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## Shortround6 (May 11, 2013)

Tomo, look at this drawing.

http://public.sn2.livefilestore.com...Mw4ndMlX6GCY/spitfire_side.jpg?rdrts=42904509


ANd if you want the tanks to be protected you have to subtract the thickness of the protection form the thickness of the wing. Thickness of the protection is constant. Weight per sq. ft. of protection is constant. Thin tanks well out in the wing can weigh a lot more per gallon held than tanks well inboard in the wing.


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## wuzak (May 11, 2013)

http://spitfiresite.com/2010/04/concise-guide-to-spitfire-wing-types.html/2

That's 66 UKG _per wing_.

Subtract some for the Hispano/Browning 0.50" gun bays, and you would probably still be looking at 50 UKG each wing.

So, 100 gals in the wing
+ 96 gals in the front tanks
+ 66 gals in the rear tank

=262 gals.

Add the 20 gals under the seat, and you have 282 gals. 

Spitfire Mk XIV Testing

That gives the XIV 85 gallons in the fuselage tanks plus 27 gallons in the wing tanks.

Range was 500 miles, so radius about 200?


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## OldSkeptic (May 11, 2013)

wuzak said:


> http://spitfiresite.com/2010/04/concise-guide-to-spitfire-wing-types.html/2
> 
> That's 66 UKG _per wing_.
> 
> ...



That's pushing it a bit, remember the Spit's wing gets thinner and thinner as it goes out. It was the thinnest wing around, even by today's standards.

50 gals a wing with a 20mm and a 0.5" is probably a bit too far. And it will hit roll rates badly.
26 gals (2 x 13) a wing with just a 20mm seems quite feasible, though it will affect roll rates, but not nearly so much.

Look at my calcs, that still gives a 600 miles combat range. Well beyond Berlin from SE England bases.


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## wuzak (May 11, 2013)

OldSkeptic said:


> That's pushing it a bit, remember the Spit's wing gets thinner and thinner as it goes out. It was the thinnest wing around, even by today's standards.



66 gallons is what they put into that tank according to that website.




OldSkeptic said:


> 50 gals a wing with a 20mm and a 0.5" is probably a bit too far. And it will hit roll rates badly.
> 26 gals (2 x 13) a wing with just a 20mm seems quite feasible, though it will affect roll rates, but not nearly so much.



I suppose if you can't use that fuel before combat it would. But then again, if you did, roll rates won't lose out by much.




OldSkeptic said:


> Look at my calcs, that still gives a 600 miles combat range. Well beyond Berlin from SE England bases.



Your calcs are based on the VIII.

I aim to get a XIV over Berlin, or beyond.

While the VIII would be good, and more than competitive over Germany, I think the XIV would dominate.


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## tomo pauk (May 11, 2013)

The Mk.VIII has a crucial advantage - it was there a full year before the XIV. With Merlin 70 it was already 25 mph faster at 25000 ft than LW opposition in 1943 (416 mph vs. 391 mph of Fw-190A-5). Conduct some streamlining and another ~10 mph should be there.



OldSkeptic said:


> Even in the PR Spits with an extra 20 gal tank in the wing had them more inboard than that (basically where the cannons are).
> 
> Remember that far out the Spit's wing is getting very, very thin, especially behind the leading edge, so there is not much room anyway.
> Debatable whether or not there is more room than in the leading edge if you dump the 0.303s. Andd at least you know there will be no structural issues using the edge.
> ...



Wuzak covered this - the PR Spits were flying with 2 x 66 of fuel in laeding edge tanks, plus whatever there was in fuselage. With volume allocated for gun barrels, the fuel should be around 2 x 55 IG, in unprotected tanks. The self-sealing would 'steal' some volume.



Shortround6 said:


> Tomo, look at this drawing.
> 
> http://public.sn2.livefilestore.com...Mw4ndMlX6GCY/spitfire_side.jpg?rdrts=42904509
> 
> ...



Thanks for the link, I just love schematics.
As yo can see, my proposal does not use the outer quarter of the LE volume, so the weight penalty per gallon carried should be reasonable. Using the historic LE tank used in Mk.VIII as a rough rule of thumb, we could expect maybe 2 x 40 IG of fuel there, in self-sealing tanks.


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## tomo pauk (May 11, 2013)

duplicate - please delete


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## wuzak (May 11, 2013)

tomo pauk said:


> The Mk.VIII has a crucial advantage - it was there a full year before the XIV. With Merlin 70 it was already 25 mph faster at 25000 ft than LW opposition in 1943 (416 mph vs. 391 mph of Fw-190A-5). Conduct some streamlining and another ~10 mph should be there.



Yes, and the XIV starts rolling off the production line not much later than the P-51B starts arriving in England.

But not in large numbers.

I wonder what the hold up is?

I suspect it is a combination of factors. 1) The IX has precedence over the VIII in production, 2) Griffons weren't being built in big enough numbers.

The XIV is basically a Griffon powered VIII. The IX wasn't suiable as a base for the XIV. So if factories were spitting out VIIIs in 1942/43 they would have been easier to turn to XIV production than IXs.


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## OldSkeptic (May 11, 2013)

Trouble Wuzac that then becomes a 'what-if' alternative history. 

I used the Mk VIII for calculations, but if they had really gone for large scale production of a LR Spit in 43 they would have more than likely retro-fitted existing IXs with VIII leading edge tanks (and the larger front tank plus the rear tank) and of course added them to new ones coming off the production line.

So you would have seen a hybrid IX with VIII tanks, at least until VIII production ramped up.

And those wing tanks count, even with just the standard 26 gal ones. Without them you your max combat range is 400miles.

As for the XIV, they did trial 75 gals tanks but when they actually fitted rear tanks they used 66 gals. 
But, push comes to shove and with the greater weight and length of the Griffon helping the CoG issue you could theoretically get:
Front: 96 gals
Rear: 75 gals
Wing: 52 gals
Drop tank: 90 gals
Gives 233 gals in total internal (313 with drop tank).

That will get a get a XIV to Berlin and back, though a bit tight.
But if you can be a little less conservative and leave some fuel (say 20 gals) in the rear tank for combat and the return trip, actually even 10 gals would do it comfortably (niot recommended for the IX/VIII but you might get away with it on a XIV perhaps with a whopping big bob weight on the elevator control).

On rough calculations, 10 gals left in the rear tank would mean a reserve for the XIV of 28 gals on a 500 mile combat mission.

Note that I have always allowed an absolute min of 15 gals (more is needed for a XIV) as a reserve for all the calculations shown previously, got to allow a fair amount for winds, weather, enemy action, etc.


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## Shortround6 (May 11, 2013)

tomo pauk said:


> Thanks for the link, I just love schematics.
> As yo can see, my proposal does not use the outer quarter of the LE volume, so the weight penalty per gallon carried should be reasonable. Using the historic LE tank used in Mk.VIII as a rough rule of thumb, we could expect maybe 2 x 40 IG of fuel there, in self-sealing tanks.



Look again and look at the rib sections in the lower right hand corner. By the time you get to the 4th gun the wing is about 1/2 the thickness it is at the beginning of the wheel well and start of the "normal" leading edge tank.
Even rib 14 (just inboard of the of the 2nd gun) shows a sizable reduction cross section of the leading edge compared to Rib 5. 

And here is a link to a photo of the inside of the leading edge. 

http://www.vintagewings.ca/Portals/0/Vintage_Stories/News Stories E/Just Wingin' It/Wings10.jpg

Trying to fit large tanks in the leading edge WITH protection is going to be a nightmare.


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## OldSkeptic (May 12, 2013)

Shortround6 said:


> Look again and look at the rib sections in the lower right hand corner. By the time you get to the 4th gun the wing is about 1/2 the thickness it is at the beginning of the wheel well and start of the "normal" leading edge tank.
> Even rib 14 (just inboard of the of the 2nd gun) shows a sizable reduction cross section of the leading edge compared to Rib 5.
> 
> And here is a link to a photo of the inside of the leading edge.
> ...



Perfectly correct, concentrating on outer leading edge tanks is more practical.

Been doing some checking and Boscomb Down cleared the FR XIV for combat with about 15 gals in the rear tank.
Given that Berlin in a XIV is possible, even with just the standard inner leading edge tanks.

One thing I need to find out is that the VIII had 96 gals in the 2 front tanks (the IX had the usual 85 gals) but the XIV reverted to the 85 gals.

Not sure why that was, since the XIV is a VIII with a Griffon, unless there was some sort of issue with space. Any ideas would be useful.


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## wuzak (May 12, 2013)

Griffon was actually shorter than the Merlin. So there shoudl have been more space.

Maybe it needed a bigger oil tank?


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## tomo pauk (May 12, 2013)

OldSkeptic said:


> ...
> 
> One thing I need to find out is that the VIII had 96 gals in the 2 front tanks (the IX had the usual 85 gals) but the XIV reverted to the 85 gals.
> 
> Not sure why that was, since the XIV is a VIII with a Griffon, unless there was some sort of issue with space. Any ideas would be useful.



Contrary to Merlin Spitfires, the Mk.XIV carried engine oil between top fuel tank and engine. Per 'Spitfire - History', pg. 419 cutaway.

added: the drop tank from the P-38, 126 IG (150 USG), would not looked bad on the Spitfire either.


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## drgondog (May 12, 2013)

OldSkeptic said:


> Perfectly correct, concentrating on outer leading edge tanks is more practical.
> 
> Been doing some checking and Boscomb Down cleared the FR XIV for combat with about 15 gals in the rear tank.
> Given that Berlin in a XIV is possible, even with just the standard inner leading edge tanks.
> ...



I don't have access to the weight/balance charts that were used to calculate the CG for fixed and disposable loads. My speculation is that a.) the Griffon is longer, thereby reducing space, b.) probably heavier. 

Possibly the combination of more engine mass forward, combined with more fuel forward could have had an adverse effect on Take off relative to 'forward' cg issues.


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## wuzak (May 12, 2013)

drgondog said:


> I don't have access to the weight/balance charts that were used to calculate the CG for fixed and disposable loads. My speculation is that a.) the Griffon is longer, thereby reducing space, b.) probably heavier.



According to Lumsden, the 2 stage Merlin is 88" long, and the 2 stage Griffon is 81" long. So the Griffon is shorter.

But it is definitely heavier -1640-1670lb for the Merlin (depending on accesories) vs 1980lb for the 2 stage Griffon (100 series Griffons were slightly heavier, because they had 3 speed supercharger drives and many had CR prop shafts). 




drgondog said:


> Possibly the combination of more engine mass forward, combined with more fuel forward could have had an adverse effect on Take off relative to 'forward' cg issues.



I do believe the XIV is longer, so the engine is more forward.

But to counteract that they put balance weights in the tail.




drgondog said:


> I don't have access to the weight/balance charts that were used to calculate the CG for fixed and disposable loads.



Spitfire Mk XIV Testing

Does that help?


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## tomo pauk (May 12, 2013)

Shortround6 said:


> Look again and look at the rib sections in the lower right hand corner. By the time you get to the 4th gun the wing is about 1/2 the thickness it is at the beginning of the wheel well and start of the "normal" leading edge tank.
> Even rib 14 (just inboard of the of the 2nd gun) shows a sizable reduction cross section of the leading edge compared to Rib 5.
> 
> And here is a link to a photo of the inside of the leading edge.
> ...



Great photo.
In order to accommodate the LE fuel tanks, the Spitfire VII/VIII/XIV have had leading-edge ribs 6 and 7 removed (together with 'W' shaped supports), while the top and bottom skin were doubled in order the wing retains rigidity. I would not bet my house on this, but it does not seem too much a stretch: do the similar thing with the remainder of the leading edge, while installing the self sealing tanks between ribs 10-16 (start of the outboard .303 gun bay).


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## parsifal (May 13, 2013)

thinking outside the box for a second, what about trade offs to achive weight savings so as to increase the fuel load? What might be considered expendable or reducable?

Armament
Armour
Radio
Ammunition supply

Any others?


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## wuzak (May 13, 2013)

parsifal said:


> thinking outside the box for a second, what about trade offs to achive weight savings so as to increase the fuel load? What might be considered expendable or reducable?
> 
> Armament
> Armour
> ...



I thought the issue would be finding the volume to place the fuel, not the weight.


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## parsifal (May 14, 2013)

maybe, but one would think that the elliptical wing with all that volume, would make an odeal integral fuel tank, along the lines of the zero and its internal fuel tankage arrangements. has some nasty side effect ("flying ronson"), but I would not think volume or space was such an issue.


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## wuzak (May 14, 2013)

parsifal said:


> maybe, but one would think that the elliptical wing with all that volume, would make an odeal integral fuel tank, along the lines of the zero and its internal fuel tankage arrangements. has some nasty side effect ("flying ronson"), but I would not think volume or space was such an issue.



That lovely elliptical wing is thinner than most in its era. 

It had a 13% thickness to chord ratio at the root (~16% for the P-51). But it also was an older, non-laminar flow, section - that means the thickest point is closer to the leading edge than for the P-51. The Leading edge, and just behind the main spar would make for reasonable spaces for fuel storage, but after that, not so much. Also have to have structure in the wing, guns, coolers and landing gear. I guess if teh coolers were moved to teh fuselage, some space could have been made there.


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## Neil Stirling (May 14, 2013)

Planned long range Spitfire XXI







Neil.


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## tomo pauk (May 14, 2013)

Great stuff 

Neil, would it be possible top post the aircraft data sheets for the other Spitfires with one or two rear fuselage tanks? Maybe also for the PR/FR versions?


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## fastmongrel (May 14, 2013)

Why the effort to get to Berlin. Leave the big city to BC at night and concentrate on turning the Ruhr into a wasteland by day. For this the LR MkVIII Spit with 90 gall slipper tank and rear fuselage tank would have been fine without cramming fuel into every available space.


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## Neil Stirling (May 14, 2013)

Neil

Last three images got through some how and are not what was asked for.


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## Neil Stirling (May 14, 2013)

Neil.


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## tomo pauk (May 14, 2013)

Neil Stirling said:


> Last three images got through some how and are not what was asked for.



No problems about that 
If we would post only what was asked for, the forum would've been a dull place.


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## Camden (May 14, 2013)

I've sometimes wondered why the Hispano V wasn't produced earlier. The measures used to increase the rate of fire (shorter barrel; lighter bolt) were all well-understood pre-war and could easily have been introduced in 1940. You could fit 2 of these to a Spitfire and remove the Hispano II's and machine-guns without any significant change in firepower, then fit extra tanks where the mg's had been. Once the wing tanks were empty, the aircraft would also be about 150-200 pounds lighter than the actual aircraft, and would probably have a somewhat better roll-rate.


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## Aozora (May 14, 2013)

Neil Stirling said:


> Planned long range Spitfire XXI
> 
> View attachment 233329
> 
> ...



Shown below are the fuel systems and capacities of the Seafire 45 and 46, which are the same as, or very similar to, the Spitfire 21/22:














The main problem I can see was the numbers of tanks and the handling required; lots of things to go wrong:










One of those images slipped through totally accidentally.


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## parsifal (May 14, 2013)

youve done it again Aozora......what were we discussing????


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## OldSkeptic (May 14, 2013)

Me too, I've completely lost track of the thread


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## gumbyk (May 14, 2013)

With that pic, I lost track of which website I was looking at!


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## nuuumannn (May 14, 2013)

> One of those images slipped through totally accidentally.



Must be one of the fuel diagrams; the rest look perfectly normal to me. In fact, it looks like my bedroom wall when I was a teenager...


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## OldSkeptic (May 15, 2013)

> "The main problem I can see was the numbers of tanks and the handling required; lots of things to go wrong: "




Hmmm can see why...


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## OldSkeptic (May 15, 2013)

Getting back on tack (somehow) that's interesting (I mean the Spit ... clean your minds). Obviously the wing thinness is affecting the capacity, plus the 2x20mm.

But even that, plugging it into my model, gives a 550 miles combat radius with a 120 mile reserve on the return. That's more than enough in '43 to make a big difference.
Even a big help post June 44 for many except the really long missions, because the escorts often found themselves very stretched on a numbers basis, until the Luftwaffe finally collapsed.

Having even just few extra wings of LR Spits (ideally far more) would have been of tremendous help to the US Mustang fighter groups, those guys got really pushed at times (when you read their accounts).

To answer a point raised: I use the 500 miles to Berlin as a yardstick, because if you draw a radius with that distance it covers a lot of Germany and many important industrial centres.


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## wuzak (May 15, 2013)

On Mike Williams' site there is a reproduction of an AFDU tactical trials report on the Spitfire XIV.

Some of the conclusions are interesting:



> Even with the 90 gallon tank, the Spitfire XIV can equal or outclass the FW.190 (BMW.801D) and the Me.109G in every respect. Its main advantages remain the tight turn and maximum climb.



and 



> The Spitfire XIV has a slightly better maximum climb than the Spitfire IX, having the best maximum rate of climb yet seen at this Unit. In the zoom climb the Spitfire XIV gains slightly all the way, especially if full throttle is used in the climb.



So, presumably the Spitfire XIV could have gone into combat with is long range tank in place and partially full.

vs the Spitfire IX



> At all heights the Spitfire XIV is 30-35 mph faster in level flight. The best performance heights are similar, being just below 15,000 and between 25,000 and 32,000 ft.



vs the Spitfire VIII



> Performance- Speeds near the ground are identical, at 10,000 and 15,000 feet *the Spitfire VIII is faster*, at 20/25,000 ft. similar, at 30,000 ft. and over the Spitfire XIV accelerated faster and was the superior aircraft.
> 
> Climb- Zero to 30,000 feet the Spitfire VIII is the better aircraft, at 30,000 ft. and over the Spitfire XIV is by far the better.



Interesting that the speed of the VIII was considered equal to that of the XIV, since the IX was 30-35mph slower than the XIV at all heights. This was an early conversion aircraft, the tests taking place in late July 1943. Would this suggest that the XIV (VIIIG) tested wasn't as fast as the production version comapred to the IX.


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## Aozora (May 15, 2013)

From a post war report written by a former O.C of the AFDU (Sqn Ldr Wade) as shown in WW2 Aircraft performance Comparative Performance of Fighter Aircraft: 







In this he showed that the Spitfire XIV had a combat radius of just over 230(?) miles (Spitfire 21 c. 280 miles, Spitfire XIV c. 390miles) based on the following conditions:



> In all cases the range is given at the individual aircraft’s rated altitude, with full complement of drop tanks where applicable. Throttle settings are standardized in that five minutes are allowed for take-off at full power, climb at maximum throttle settings to rated altitude, five minutes combat at full throttle, 15 minutes at maximum cruising and the balance at economical cruising. This method is purely arbitrary, and should not be taken as representative of an operational sortie.



the normal fuel capacity of the XIV was 111 gallons (top and bottom main tanks, 2 wing LE tanks: from Pilot's Notes) + 90 gal = 201 Imp gal (although Wade wrote 199 gal), so even with the 90 gal drop tank the ordinary Spitfire XIV would have struggled to be a useful long-range fighter, even flying at economical cruising speeds for the entire flight.






In my previous posting I was showing the improved fuel capacities of the late model Spitfire/Seafires with the revised wing, which could carry more fuel in the outer leading edges. The downside was a complicated fuel system, particularly the Seafire 46/Spitfire 22 with 3 drop tanks and the fuselage tank, ten tanks in total, meaning seven sets of fuel tanks to manage for a total capacity of 247 gal. Cf the P-51 which had five fuel tanks (two wing, fuselage tanks plus drop tanks), yet almost twice the fuel capacity.


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## Shortround6 (May 15, 2013)

Camden said:


> .... and machine-guns without any significant change in firepower, then fit extra tanks where the mg's had been. Once the wing tanks were empty, the aircraft would also be about 150-200 pounds lighter than the actual aircraft, and would probably have a somewhat better roll-rate.



The Problem with the Spitfire ( and many other fighters) was NOT getting TO the fight, that was handled by drop tanks. The Problem was GETTING HOME from the fight. That requires protected fuel tankage that is FULL or nearly so when the fight starts.


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## zjtins (May 15, 2013)

> Clean sheet of paper


 What bender said. 

Moding a simple passenger plane is very difficult to get right... let alone a high performance fighter. There are so many factors that must be considered to the get all the performance variables into acceptable ranges at all altitudes and speeds(it that is required).
We all talk about eh P-51 wonder plane made in 90 days but how many attempts failed? From clean sheet designs in that era?

Willy Messerschmidt tried with 109, one of the top minds of his day and could only be considered a modest success.

The Spitfire was good in the BoB bu twas the same as the ME-109, more current designs outclassed it.


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## Njaco (May 15, 2013)

> Willy Messerschmidt tried with 109, one of the top minds of his day and could only be considered a modest success.
> 
> The Spitfire was good in the BoB bu twas the same as the ME-109, more current designs outclassed it.



maybe I'm mis-reading this but could you explain how either the Bf 109 or Spitfire were "modest success'"?


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## nuuumannn (May 15, 2013)

> Willy Messerschmidt tried with 109, one of the top minds of his day and could only be considered a modest success. The Spitfire was good in the BoB but was the same as the ME-109, more current designs outclassed it.



Geez, some people need to read up on their aviation history. There's no 'D' in _Messerschmitt_ for starters. The Bf 109 was built in greater numbers than any other fighter; it was in production before and after the war and was enormously successful and remained front line equipment with the Luftwaffe until the end of the war, despite the Fw 190 and Me 262. As for the Spitfire, like I said in another thread, there were only two occasions when the Spitfire was bested by its German opponents, the Spit V against the Bf 109F and Fw 190 - and we know what happened next, the Spit IX, and the advent of jet fighters, which overtook all piston engined fighters - even still, the Spit remained in RAF service until 1952. Constant innovation and modification kept the Spitfire current throughout the war.

Chris, you're being far too diplomatic.


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## drgondog (May 15, 2013)

Interesting that the Thunderbolt II was declared winner in combat radius - as capable of going to Vienna and back - when it never made an operational mission to Munich and only two as far as Berlin during WWII.


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## FLYBOYJ (May 15, 2013)

zjtins said:


> Willy Messerschmidt tried with 109, one of the top minds of his day and could only be considered a modest success.



Almost 34,000 units built during WW2, with another 200 HA1112s built in Spain and 600 built by Avia, along with an operational life from 1937 - 1965 from all variants, yea, I think it was only a "modest success."  

Oh, I also think the -109 destroyed more aircraft in aerial combat than any other combat aircraft in the history of aerial warfare. Yep, a modest success


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## DerAdlerIstGelandet (May 15, 2013)

Wow, I don't know what to say. The 109 only modest success? The Spitfire just good?

Someone should really stick to net gear and welding discussions.


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## fastmongrel (May 15, 2013)

Sounds like someone has been reading A simple knowledge of everything by Stewart Davies and is Shooting but missing.


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## zjtins (May 15, 2013)

Production numbers alone don't tell the whole story. By the at measure the P-51 and P-47 were only half as good as the ME-109.

And they also destroyed more obsolete aircraft than any other.

So if your measure of success is only production numbers and number of obsolete aircraft shot down then you should go to all the threads about best this or that and give them your 2 cents.

If you want to have a discussion on why I say what I said, be happy to.


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## FLYBOYJ (May 15, 2013)

zjtins said:


> Production numbers alone don't tell the whole story. By the at measure the P-51 and P-47 were only half as good as the ME-109.


And can you qualify that in operational terms with regards to maintenance or from a pilot's perspective?


zjtins said:


> And they also destroyed more obsolete aircraft than any other.


As well as "non-obsolete." And can you define what you consider "obsolete"? The last time I looked I believe warfare involved removing your enemy's will to fight and that might be achieved by the destruction of said army or in this case air forces - I think its irrelevant what's obsolete or not.


zjtins said:


> So if your measure of success is only production numbers and number of obsolete aircraft shot down then you should go to all the threads about best this or that and give them your 2 cents.


I should and have and will....


zjtins said:


> If you want to have a discussion on why I say what I said, be happy to.


I'm all ears....


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## DerAdlerIstGelandet (May 15, 2013)

So the P-51s, Spifires, P-38s,'P-47's that were shot down were all obsolete?

I too am all ears...


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## zjtins (May 15, 2013)

> And can you qualify that in operational terms with regards to maintenance or from a pilot's perspective?



Does this mean performance, reliability, firepower, ruggedness, range all do not matter to you?

All (almost) the Russian plans at the beggining of the war were obsolete. Even the next few models out of there design bureaus were not good (not my words... Ralls.)

Depending upon how one breaks up the time frames, the Germans never lost more than 1:1 until 1945 in the eastern front (except for individual locales or short time frames). 
I have seen some published accounts shoe the Russian Air force gone with only a handful of Germans shot down by aircraft in the begging. 

Then the German have to pick between anti fighter and anti bomber. Anyone here care to show how good a ME-109 with 2x20mm or 30mm slung beneath its wing was better than just about any western fighter of the time? 

Ralls one words were he like the model the best for fighter vs fighter, but he was the best what about the other 99% untrained inexperienced pilots? Most died swiftly.

Like I said after the BoB the ME-109 was only a modest success. You only have to look at the FW-190 for more successful model. When it was re-engined it became far more difficult an adversary, 4x cannon and 2 HMG, was more rugged due to internal construction (Mess gave up alot for speed), also much better vision. And if you want to count the morphing into the TA-152, yet a higher grade still especially at altitude. But the war ended with little contribution.


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## zjtins (May 15, 2013)

> So the P-51s, Spifires, P-38s,'P-47's that were shot down were all obsolete?



Lets start there, how many for the ME109 vs FW190 vs flak vs other? And how ME109 and FW190s were shot down by those aircraft mentioned. 
Someone provide the numbers because if I do I get too much flak (no pun intended). I will accept pretty much any source the rest sign up to.


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## DerAdlerIstGelandet (May 15, 2013)

zjtins said:


> Lets start there, how many for the ME109 vs FW190 vs flak vs other? And how ME109 and FW190s were shot down by those aircraft mentioned.
> Someone provide the numbers because if I do I get too much flak (no pun intended). I will accept pretty much any source the rest sign up to.



Why don't you start here. 

Kacha`s Luftwaffe Page

You get Flak because you claim things that prove you are over your head.


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## Njaco (May 15, 2013)

I didn't know Erich Hartmann only flew the "successful" Fw 190.... who knew?


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## FLYBOYJ (May 15, 2013)

zjtins said:


> Does this mean performance, reliability, firepower, ruggedness, range all do not matter to you?


It does, now applied to what aircraft and during what era? If you want to discuss this with regards to the -109 it was all of the above. Were there "better" aircraft with regards to those traits? Yes, but that still doesn't diminish the -109


zjtins said:


> All (almost) the Russian plans at the beggining of the war were obsolete. Even the next few models out of there design bureaus were not good (not my words... Ralls.)


The -109 did not only shoot down Russian Aircraft, at least the last time I looked...


zjtins said:


> Depending upon how one breaks up the time frames, the Germans never lost more than 1:1 until 1945 in the eastern front (except for individual locales or short time frames).
> I have seen some published accounts shoe the Russian Air force gone with only a handful of Germans shot down by aircraft in the begging.


And your point?


zjtins said:


> Then the German have to pick between anti fighter and anti bomber. Anyone here care to show how good a ME-109 with 2x20mm or 30mm slung beneath its wing was better than just about any western fighter of the time?


It wasn't, but it sure knocked down a lot of allied bombers...


zjtins said:


> Ralls one words were he like the model the best for fighter vs fighter, but he was the best what about the other 99% untrained inexperienced pilots? Most died swiftly.


And pilot training has what to do with showing the success of the -109?


zjtins said:


> Like I said after the BoB the ME-109 was only a modest success. You only have to look at the FW-190 for more successful model. When it was re-engined it became far more difficult an adversary, 4x cannon and 2 HMG, was more rugged due to internal construction (Mess gave up alot for speed), also much better vision. And if you want to count the morphing into the TA-152, yet a higher grade still especially at altitude. But the war ended with little contribution.


The -190 was most certainly a better aircraft, it also came along several years later as did the P-51, P-47 and later versions of the Spitfire. I think you're confusing "success" with performance. the -109 did have limited growth potential but was still a force to be reckoned with even later in the war. If anything marginalized the -109s capability, one should look at campaign tactics and how the aircraft was deployed.


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## OldSkeptic (May 15, 2013)

Shortround6 said:


> The Problem with the Spitfire ( and many other fighters) was NOT getting TO the fight, that was handled by drop tanks. The Problem was GETTING HOME from the fight. That requires protected fuel tankage that is FULL or nearly so when the fight starts.



100% correct. That's what my (albeit simple) model calcs.

You put in the internal tankage, add drop tanks, put in the range required and combat time.

It then works through, using the pilots note figures.
Climb and takeoff on the rear tank. Initial cruise on rear tank until empty. Then the drop tank. Until you get to range required.
The drop tank with all remaining fuel is then excluded (dropped so to speak). 

The fuel used for the combat time is taken off the internal tanks, then the remaining internal fuel is used for the return.
Most economical cruising speed is used except for the combat time, with an allowance for the higher fuel consumption when carrying the drop tank.

On the original calcs, with the Mk VIII internal fuel plus a 66 (UK) gal rear tank, a 500 mile escort radius leaves a 15 gals (101 miles) reserve, 7.7% of the total internal fuel, or 20% of the required return range.
In fact the 90 gal drop tank has 53 gals left when it is dropped. Which leaves a large allowance for rendezvous issues (having to hang around because the bombers are late, or using some more speed to catch up if the bombers are ahead of schedule). 

It is quite conservative in that it assumes that the climb is not used to head towards the target. Also that the bombers are attacked at the maximum range, so there is the minimum internal fuel for return.
If the bombers are attacked before the maximum range is reached then the fighters, after combat will usually return from that shorter range. Apart from anything else they will usually be out of ammo anyway.
That is what happened in real life with the Mustangs most of the time. If they were attacked then after the combat the ones actually involved usually returned (others not involved remained of course).


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## OldSkeptic (May 15, 2013)

> The -190 was most certainly a better aircraft, it also came along several years later as did the P-51, P-47 and later versions of the Spitfire. I think you're confusing "success" with performance. the -109 did have limited growth potential but was still a force to be reckoned with even later in the war. If anything marginalized the -109s capability, one should look at campaign tactics and how the aircraft was deployed.



Overall I agree. But there was the issue of a lack of an alternative high altitude fighter. The 190A's performance dropped off pretty quickly and because of the high altitude of the US bombers was not at its best performance envelope. The 190D was a partial fix for that, but that came pretty late on.

Because the Germans had stuffed around for so long trying to come up with an alternative fighter all they had left was the 109 for that higher altitude work, and of course it was easy to manufacture.

They got caught in that terrible logic trap that you see all too often, they never fixed up (which I'm sure they were perfectly capable of within a very short time) the major weaknesses of the 109 because the of 'next' fighter that was going to replace it. Which never happened. So they ended up with the worst of all possible worlds.

Take a simple example and contrast with the Spits development and the different attitude. The 109 had long standing aileron and elevator issues. Now a revised tailplane should have been able to have been worked out within a month or so and then put into production. Ditto the ailerons. They fixes didn't need to be perfect, just better than what they were replacing.

The more logical approach is shown with the Spit and its aileron and CoG issues are a total contrast. They got a quick fix by going to metal ailerons and introduced bob weights as a quick CoG fix (for the Mk Vs). Further testing showed that a revised elevator horn would do the job, which was then introduced and the bob weights removed.

So they didn't wait for years until a successor plane (or a total revision like the Mk XVIII) was introduced, they just got on with it and fixed it to the bet of their abilities at the time.
You can see a similar attitude with the Mustang, introducing the tailplane strake.

Basically good enough was good enough, rather than wasting years striving for perfection.

Those quick 109 fixes would have improved its operational abilities markedly, then an updated (like a 190A to D, or Typhoon to Tempest revision) could have been introduced a bit later. 
Longer fuselage, revised tailplane, bigger wings, that sort of thing. One of the things you would aim for was to extend its effective combat operating envelope, so that it was more effective at mid/low altitudes and high speeds, where those aileron and elevator issues were at their worst, rather than just the high altitudes.

As it was, it was still very dangerous at higher altitudes right to the end.


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## wuzak (May 15, 2013)

OldSkeptic said:


> So they didn't wait for years until a successor plane (or a total revision like the Mk XVIII) was introduced, they just got on with it and fixed it to the bet of their abilities at the time.



The XVIII was an updated XIV. The wing was teh same as the XIV, which was the same as the VIII on which it was based.

The VIII wing was strengthened - but I'm not sure whether it was specifically for that model, or for all models then in production?

The 21 used the new wing, and would be the "totally revised" version.


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## OldSkeptic (May 16, 2013)

wuzak said:


> The XVIII was an updated XIV. The wing was teh same as the XIV, which was the same as the VIII on which it was based.
> 
> The VIII wing was strengthened - but I'm not sure whether it was specifically for that model, or for all models then in production?
> 
> The 21 used the new wing, and would be the "totally revised" version.



Sorry I should have said the XX. But the XVIII did have a strengthened wing, but more to increase load carrying than improved torsional strength to improve aileron performance. 

The Spit went through a couple of upgrades that improved its aileron performance. The first was the metal ailerons, but the introduction of the universal wing in the MK V was thicker skinned and torsionally stronger, pushing up the aileron reversal speed still further.

So it's reversal speed started about 480 mph, compared to a maximum theoretical of 545mph. But the fabric ailerons ballooning increased stick force well before the theoretical limits. 
The metal ailerons plus the universal wing increased that markedly to 580mph.
The roll rates of the clipped wing were much faster and their performance dropped more slowly than for a standard wing. I suspect the plug used to close off the wing when the wingtips were removed also stiffened it torsionally a little bit more.

It was also very sensitive to how well the cables were adjusted and over time they changed procedures and added some extra tools to help set them up better. Some of the poor results very early on probably came from poor setup. 

So until the XX they never totally overcame the issue, but they managed to improve it markedly And that was what was needed at the time. Much more sensible to have something 'better' now, than waiting for 'perfection' much, much later.

There was no real change in the wings for the MK VIII, but the fuselage was strengthened for better load capacity (essential for the Griffon version).


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## zjtins (May 16, 2013)

Question would anyone here still debate this if a replacement had worked in late `43 like the ME309?

Based on production limitations for Germany to convert to another plane after that would have put a hole in the output of fighters when they needed them the most. I submit that Germany kept producing versions of the ME-109 after late 43 because they had no real choice. Tooling, parts, production, build lines all were set up for the 109. Until the ME262 came along (and Hitler let go of the bomber concept and jet engines were developed to a minimal level which can also be debated) the new concepts did not gain enough in their eyes to be worth the lost production.

My theory is they never built larger air cooled versions so there was no option there yet Russia, Japan, and the US all did that successfully. So they were already pushing out liquid cooled revisions as fast as they could, some did not work, others also went to bombers limiting fighter use. 

As for quoting German fighter ace records, anyone care to show how many kills they scored pre Jan1944 and post Jan 1944? And how many of said aces died in combat pre and post Jan1994?
Also the same numbers for non aces to see how many were slaughtered in the 'great 'plane. Without those numbers the fighter Ace records are only records, there is no context.


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## OldSkeptic (May 16, 2013)

> Based on production limitations for Germany to convert to another plane after that would have put a hole in the output of fighters when they needed them the most.



Quite true. By that time it was too late, the bad decisions made in 40/41 42 now came to haunt them. Perhaps they should have brought in Kurt Tank and his team to work out an upgraded version in 41


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## drgondog (May 16, 2013)

zjtins said:


> As for quoting German fighter ace records, anyone care to show how many kills they scored pre Jan1944 and post Jan 1944? And how many of said aces died in combat pre and post Jan1994?
> Also the same numbers for non aces to see how many were slaughtered in the 'great 'plane. Without those numbers the fighter Ace records are only records, there is no context.



The question has no context - are you interested in German Fighter aces that became aces in 109s, then were killed in same? the number of German 109 pilots KIA that had more than 500 hours, or less than 250, but not aces? the number of aces that started flying pre-1939, the number of aces that started after 1942 or after 1943? The number of Aces KIA in west against RAF and USAAF vs VVS? The number of aces that survived war versus the ones that fell?

If you had all that data what would you surmise?


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## Njaco (May 16, 2013)

Hitler did not stone-wall the production of the Me 262 as much as the need for materials did - the very same materials that were being destroyed by the 8th AF - you know, those aerial operations that really didn't have an effect on the war.

Remember this:


> They did not know then but we know now the air raids on Germany did only a modest affect on the production of necessary material, aside from keeping troops home as anti-aircraft units which was a significant factor.



http://www.ww2aircraft.net/forum/aviation/hellcat-vs-spitfire-would-you-take-36880-27.html


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## zjtins (May 17, 2013)

> Hitler did not stone-wall the production of the Me 262 as much as the need for materials did - the very same materials that were being destroyed by the 8th AF - you know, those aerial operations that really didn't have an effect on the war.



Post war BDA comparison showed a factory bombed is not a factory destroyed. The tools were essentially untouched. I cant remember who but one of the interviews with a German ME262 pilot clearly stated had Hitler not wanted a bomber some ME262s would have been available in 43. The question is then how many and to what affect. Dont believe it would have won the war but it would have hurt more. 

You whole assertion of a significant affect on German war production is not supported by the number available. In 1944 they produce more of ever category they chose to increase, usually by wide gains. This was attributed by most as finally putting German economy on a War footing in late '43 with Speer in charge.

A far bigger consequence to production was transportation limitations and lack of critical raw materials, nickel, chrome, manganese, molybdenum, copper etc. Germany had no local sources. 
By 1943 low and mid altitude bombers and fighter bombers were tearing up rail yards, trains, trucks, anything that moved or enabled movement. If a factory can't get part or raw materials it cant produce. But this did not seem to register until late '44 which coincided with reduce the need for bomber fighter cover and released the fighter bombers for ground attacks.


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## Hop (May 17, 2013)

> Post war BDA comparison showed a factory bombed is not a factory destroyed. The tools were essentially untouched. I cant remember who but one of the interviews with a German ME262 pilot clearly stated had Hitler not wanted a bomber some ME262s would have been available in 43. The question is then how many and to what affect.



Fighter pilots are not engineers or managers. They are not authorities on the details of what does and doesn't get built, and when.

Hitler first asked if the 262 could carry bombs at a meeting in the autumn of 1943. He was told it could. On 26 November Hitler inspected a prototype 262 and asked Willi Messerschmit if it could carry bombs. Messeschmit assured Hitler it could carry 1 1,00kg or 2 500kg bombs. Hitler was satisfied. 

On 23 May 1944 Hitler was at a meeting discussing aircraft production. He asked how many of the Me 262s built so far could carry bombs. Milch told him that none of them could. No design work had been done on fitting them with bomb racks.

At that point less than 50 262s had been built, their engines were very unreliable, and they were all being used for pilot training and testing.

Hitler's order about fitting bombs to the 262 delayed the programme slightly after May 1944. But the aircraft was nowhere near combat ready until late 1944 (if then). There is no way they could have been in service in 1943, not even by the summer of 1944. At best, without Hitler's interference, there would have been a handful more fighter 262s in service in the autumn of 1944.

It wasn't really materials that held back the 262 either, it was simply the problems of designing and building a brand new type of engine.


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## tyrodtom (May 17, 2013)

From 1940 to 44, German aircraft production went from about 11,000 aircraft per year to 41,000 , not quite a 4 times increase.
The USA went from 6,000 to 96,000 in the same time span, a 16 times increase. And i'll bet those 44 figures for Germany have a greater % of single engine fighters than the US figures.

IMO Germany would have been capable of a much greater increase if they'd been unhindered by bombing like the US.


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## Shortround6 (May 17, 2013)

Actual numbers for the US for combat and large transports was from 3,064 to 80,938 aircraft ( gets rid of trainers of small transports) for 26.4 times increase. For pounds of airframe for combat and large transports it went from 17,176,700lbs to 930,593,400lbs for over a 54 times increase and engine HP (not engines) went from 15,723,000hp to 423,196,000hp for 26.9 times. 

The Germans would have done better without being bombed, how much better?


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## zjtins (May 17, 2013)

> IMO Germany would have been capable of a much greater increase if they'd been unhindered by bombing like the US.


The problem no one seems to consider is the lack of raw material. Germany had lots of Iron and Coal. They could make some forms of steel. At best they might have increased the output for a short while, but once a critical material was gone their design had to change to accommodate less capable metals. 
Germany by 44 and maybe late 43 was making aircraft propellers out of wood, the ME109 had a wood tail (or portions). For tanks face hardened armor was almost gone, chrome was gone from gun tubes, they had to invent the use of steel casings for rounds due to copper shortage (more weight less reliable then brass), etc. 



> The Germans would have done better without being bombed, how much better?



The Germans did not have massive production automotive and other production lines in existence like the US did at the beginning in say even 1941. Plant line conversion was much less costly and faster than new facilities, and the US still had the manpower to expand and build new facilities. The US had 3x or 4x the population with a lower percent in the military (more able to work) plus had not already lost how many millions to war already. 
Also the US led in production technology specifically, cast tanks hulls, liberty ship sectional manufacturing (4 a day!?), gang cutting air cooled engine piston fins on cylinders instead of forming or single cut, cast plastic technology (aircraft windshields/hoods) to name a few. Germany did not have that kind of mass production technology. 

So a comparison of the US capability to German possible capability would be extremely difficult.

Again the USAAF ran their own comparison of their own war time BDA vs after and found a serious over estimation of damage when viewed from the air vs actual affects.


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## fastmongrel (May 17, 2013)

zjtins said:


> The US had 3x or 4x the population



USA 1940 census population of 132,164,569

Germany 1942 population 72,620,000

Not quite 3 or 4 times the population. Took me a whole minute to get those figures.


GERMANY : country population

US Historical Population, by Year


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## Njaco (May 17, 2013)

So the 8th AF did nothing.

I'm getting a headache.


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## Glider (May 17, 2013)

I always thought that Bombing forced a distributed production network, which is far less efficient. Bombing forced a number of critical factories to be built underground at a huge expense of people, time, money and resources. Bombing caused a serious drain on materials making the shortages critical as well as a drain on fuel and resources to defend the targets. 
Think of the resources in electronics used to defend Germany, the radars and command and control. The significant increase on fighter losses, the need to produce fighters when a decent long range bomber force would have had significant impact on the Russian front. Bombers caused significant damage which the Germans were remarkable effective in repairing. But those repairs took massive amounts of resources. The railway distribution system was often hit, slowing down the distribution of food and materials.

I do not doubt for a second that the attackiing forces overestimated the effectivness of their attacks, its a similar to claims for kills which were almost always overestimated. However it doesn't mean that the damage was insignificant, far from it.

The Bombers of the USAAF and the RAF paid a heavy price but they also inflicted a lot of damage and without that damage German production would have been much higher.


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## Aozora (May 17, 2013)

Ah well, for all the good it did the USAAF in Britain might as well have packed up and gone to the Pacific or back to the States and let the British and Russians mop up, because by late 1943 Germany was on its last legs anyway...oy vay!


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## zjtins (May 20, 2013)

If you wish to continue to take my comments out of context then there is no discussion. 
I said the BDA post war assessment was of modest damage not zero.
Stalin wanted a second front to take pressure off of the USSR, Bombing helped do that.
Bombing did help disrupt some industry, others were already dispersed (FW190 was designed to be built in rough conditions, along road assembly, parts built in bars.) others were underground other went underground. But what the Brits also found out is destroying someones home makes them angry and more dedicated to the war effort.

Again the real limitation was resources. German simply could not have doubled production if they were left alone as at some point they ran out to material to build aircraft. They were already essentially out of Chrome and Nickel in late 44, the tiny amounts they had were spread out too far to make difference and limited to only the most critical parts. 

The bombing held whole divisions off the fronts and made them use critical materials to produce 88mm and large guns and shells to use against the bombers along with pulling fighters off the front to guard Germany.


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## Tante Ju (May 20, 2013)

zjtins said:


> The problem no one seems to consider is the lack of raw material. Germany had lots of Iron and Coal. They could make some forms of steel. At best they might have increased the output for a short while, but once a critical material was gone their design had to change to accommodate less capable metals.
> Germany by 44 and maybe late 43 was making aircraft propellers out of wood, the ME109 had a wood tail (or portions). For tanks face hardened armor was almost gone, chrome was gone from gun tubes, they had to invent the use of steel casings for rounds due to copper shortage (more weight less reliable then brass), etc.



The Germans had various shortages of critical alloys, but few that would effect aircraft production. Wood was sometimes used for propellers since the war's beginning, because it had some advantages over metal props, it was entirely out of choice. Wooden compontents were used not because of aluminium shortage (Germany was the 2nd largest producer after the US) but because it allowed the use of skilled woodworking shops for the aircraft industry. Copper was in short supply as was chromium (Turkey) and nickel (Finland) but it was not critical until the wars end; OTOH face hardened armor was simply dropped because it was not practical for the increased armor thicknesses, which called for more softer and more ductile armor that resisted rounds better, and techniques such as sloped armor (besides face hardening being time consuming and more of a question of capacity, rather than alloy). Some alloys were dropped from armored steel but were substituted by others (rather expensive, but available vanadion was used instead of molybdenium, but vanadium is also a very effective alloy). Most alloys in steel industry are replacable by others.

In the end, weapon production was never critical, though hurt by Allied bombing, the Germans always had plenty of guns. Their critical bottlenecks were fuel (which was hurt by the SBC as much as by the Red Army's advance, the latter also effected some critical alloy supplies in Ukraine) and manpower.


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## tyrodtom (May 20, 2013)

I think you mean dispersed, not disbursed.
Dispersion of the subassemblies manufactoring introduces new problems. You have to transport the parts on a schedule, otherwise you have a lot of subassemblies waiting around somewhere waiting for other parts that have to installed first. 
Sort of like the "just in time" method of manufactoring used by a lot of car manufactors today, it saves them from having to store parts in warehouses, instead the parts arrive right when they're needed, not too early, in which cased they'd have to be stored somewhere, and certainly not too late, which would mean the production line has to be stopped. 
Plus when making subassemblies in different places by different manufactors especially if under rough conditions, tolerances tend to get sloppy.


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## zjtins (May 20, 2013)

> I think you mean dispersed, not disbursed.


Thanks I grabbed the wrong word on auto correct. 




> The Germans had various shortages of critical alloys, but few that would effect aircraft production. Wood was sometimes used for propellers since the war's beginning, because it had some advantages over metal props, it was entirely out of choice. Wooden components were used not because of aluminum shortage (Germany was the 2nd largest producer after the US) but because it allowed the use of skilled woodworking shops for the aircraft industry.



Germany had zero bauxite mines in country ore came from countries they captured including, Hungary, Rumania, Yugoslavia. Now you know why Hitler took those countries. 

I did not list all metals for hardening but even as early as August 1944 German tanks on the western front were taking hit and shots penetrating that were later written penetrated up as: cause due to weak armor. There are accounts of some was so bad the armor shattered. 

They were running low so props, tail planes, flaps started to appeared at different times.


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## tomo pauk (May 20, 2013)

Maybe the German war production discussion should go in a thread of it's own, since it's way off topic here?


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## Njaco (May 20, 2013)

Make the title: "Revisionist History 101" or even better "WWII: Just Another Day At the Office".


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## zjtins (May 21, 2013)

> Maybe the German war production discussion should go in a thread of it's own, since it's way off topic here?


True


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## zjtins (May 21, 2013)

Long range-high speed Not sure what you are looking for but as compared to a P-51H why continue with a Spit? Money wasted unless as that was approaching the best you can get in a liquid cooled piston engine fighter of the time. 

Only the P47 versions with 3000 hp engines, DO-335 and possibly a P-38 with Merlins with matching props would do better (that come to mind). But all of those are at the cost for maneuverability as compared to the P-51, more of interceptors vs fighters. (also the F7F)


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## wuzak (May 21, 2013)

P-51H was a little to late to make much of a difference anywhere.

The period being talked about is 1943 into 1944, when escorts were at a premium.

Spitfire XIV would kick the arse of the P-51, P-47 or P-38 in a fight in early 1944. If only it could get somewhere useful.

I note in the report on WWII Aircraft Performance that it was considered that the XIV was superior to the German opposition even with the slipper tank in position.


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## zjtins (May 21, 2013)

Well higher speed was not in the cards due to the thick wing. Moving to laminar flow would move it into 44 when the H model was about to be developed. Also moving to laminar wing loses the Spits turning performance in the flight regimens it was famous for. Finally it still lacked the ability to mount 4x20mm cannon so it was firepower limited. 
To solve all of that would take more than a few months, and in fact later real versions never did solve that


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## tomo pauk (May 21, 2013)

zjtins said:


> Well higher speed was not in the cards due to the thick wing.



Spitfire have had thick wing??? Any numbers to back up the calim?



> Moving to laminar flow would move it into 44 when the H model was about to be developed. Also moving to laminar wing loses the Spits turning performance in the flight regimens it was famous for. Finally it still lacked the ability to mount 4x20mm cannon so it was firepower limited.



The ability to mount 4 cannons was there in 1941. Even with 2 x 20mm and 2 x .50, it's firepower was better than any Merlin Mustang, and comparable with any US fighter with R-2800 in the nose.



> To solve all of that would take more than a few months, and in fact later real versions never did solve that



Fact is that British have had modified some Spitfire IXs to carry circa 160 imp gals of internal fuel, in second half of 1944. Check out the 'RAF's long range fighters' thread in this sub-forum. Laminar flow wing would be a good addition, but they could've earned speed with refinement of raditor systems, fully enclosed main wheels, retractable tail wheel etc.


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## drgondog (May 21, 2013)

The Spit wing had smaller t/c ratio than any front line fighter. That is a fact easily validated with simple look ups. That is the Sole reason a spit could achieve a higher Mcr than both the P-51/P-47/Bf 109 and Fw 190 in a dive. The Actual wing thickness of the Spit where the 20mm were mounted is greater than the 15% T/C for the 45-100 because of the deep chord of the Spit wing compared to the P-51.

The Spit had higher drag CDo than both the Mustang and the FW, particularly the D-9.

Zjtins - the only credible thing you said was that if a laminar flow wing replaced the Spit wing airfoil, that such replacement - all else equal- the CLmax would be less and Turn performance would be reduced somewhat - but given the same comparison it should still out turn the P-51, Fw 190 and Bf 109 except perhaps at speeds below Corner speed.


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## tomo pauk (May 21, 2013)

drgondog said:


> ...
> The Spit had higher drag CDo than both the Mustang and the FW, particularly the D-9.
> ...



Bill - what would be the CD0 value for Fw-190D-9? 
The British credited Spit Vb with CD0 = 0.0213, Spit Vc = 0.0218, Spit IX = 0.0238; respective drag force ("total profile drag D0 100 (lb at 100 fps)") being 61, 63 and 66 lbs. 
For Fw-190A they give CD0 = 0.0269, drag force being 65 lbs.


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## OldSkeptic (May 21, 2013)

tomo pauk said:


> Bill - what would be the CD0 value for Fw-190D-9?
> The British credited Spit Vb with CD0 = 0.0213, Spit Vc = 0.0218, Spit IX = 0.0238; respective drag force ("total profile drag D0 100 (lb at 100 fps)") being 61, 63 and 66 lbs.
> For Fw-190A they give CD0 = 0.0269, drag force being 65 lbs.



Good points. What people seem to forget that the Spit's drag was pretty good compared to most of the other planes of the era. It wasn't particularly draggy by any means.

It was just the fact the Mustang was so good and was exceptional for that era (until the later 'super' planes like the Hornet, etc, came on the scene).


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## tomo pauk (May 22, 2013)

No doubt Mustang was the exceptional execution.

For Spitfire, we can see that CD0 increased almost 12%, IX vs. Vb (= same armament). Main culprit being the addition of inter-cooler radiator? 
Further - with better layout of whole radiator system (oil, engine, i.cooler), say, in leading edges, the CD0 goes close/under the 0.0200 mark?


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## OldSkeptic (May 22, 2013)

tomo pauk said:


> No doubt Mustang was the exceptional execution.
> 
> For Spitfire, we can see that CD0 increased almost 12%, IX vs. Vb (= same armament). Main culprit being the addition of inter-cooler radiator?
> Further - with better layout of whole radiator system (oil, engine, i.cooler), say, in leading edges, the CD0 goes close/under the 0.0200 mark?



Supermarine proposed modifying the Spit to move the radiator to under the fuselage (ah lah the Mustang) but MAP (Ministry of Aircraft Production) canned it as it would disrupt production too much..

Basically RR came coming to the party with ever more powerful engines and MAP took the pragmatic view that it was easier to follow that route than make major changes. Can't blame them.
If, RR hadn't been able to do that then they might followed a different path.

Interesting top compare the wind tunnel test of the Spit I and Mustang I. These just map the basic shapes, without the issue of things like of radiator efficiency effects, finish, etc. Plus they were on the same wind tunnel, so any distortions were common to both.

At zero coefficient of life (CL=0) the Mustang was much less draggy than the Spit, with a CD of about 0.15, while the Spit was about 0.18
At low CL (0.2) they were roughly the same at just under 0.02 up to about mach 0.7. At mach 0.75 the Spit is about 0.32 while the Mustang is about 0.38.
At CL 0.4 again very similar up to about mach 0.5, then the Spit starts to become better than the Mustang. At mach 0.7 the Spit is significantly better than the Mustang with a CD of 0.3 vs 0.34 . At mach 0.75 the Mustang is about 0.61 vs the Spit at about 0.55.


Note: all numbers can be a bit uncertain (plus or minus a bit) as I'm reading it off charts. 
Some other interesting observations, the CD of the Spit was very similar for CL 0 to CL 0.2, while the Mustang shows significant difference.

In the high mach (0.7+) region the Spitfire was consistently better, with the gap growing as the mach rose (to 0.75 or 0.8 ). 

So there was nothing wrong with the Spits shape (wings, fuselage, tail) difference came from the radiator system and details. In some areas (like tail area) it was better. The wings were probably about the same, up to high mach when the Spit's wing is better. The Engine cowling and intakes were better on the Mustang (beautiful low drag front).

Details matter a lot, the flat bulletproof windscreen cost the Spit 5mph, cannons on later models cost it another 5mph. The finish of the Mustang was far better (when new), not just the tailwheel and wheel covers, but the overall fit an finish. The Mustangs radiator had very low drag in most flight regimes and the faster it went the better it was. The Spit's (and this was a Spit I) much worse, made even worse when they went to twin radiators.

Other interesting facts: The Spit used 2 types of wing section. NACA 2213 at the root, 2208 near the tip. So not only did it get thinner the further you got out and had wing twist, the section changed (I think this was to reduce wing twist drag).


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## drgondog (May 22, 2013)

tomo pauk said:


> Bill - what would be the CD0 value for Fw-190D-9?
> The British credited Spit Vb with CD0 = 0.0213, Spit Vc = 0.0218, Spit IX = 0.0238; respective drag force ("total profile drag D0 100 (lb at 100 fps)") being 61, 63 and 66 lbs.
> For Fw-190A they give CD0 = 0.0269, drag force being 65 lbs.



Tomo - I don't have them offhand, but the Lednicer report had the Fw 190D Flat plate Drag at 4.77 to to Spit IX 5.4 and the P-51D at 4.61. I'll have to re-check the report to see the altitude and speed that the flat plate drag was calculated. 

If you have a published (reliable) flight test with GW, top speed at SL and rated Hp of the engine I can calculate it, or in the case of the Lednicer report noted above, the GW of the FW 190D for which the Drag was cited - I can extract that.

The Total Drag can be extracted from Lednicer if altitude and airspeed is say 360kts at 15000 feet - but need GW to extract Induced Drag to subtract from the Total Drag to get Parasite Drag...


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## Tante Ju (May 22, 2013)

OldSkeptic said:


> Good points. What people seem to forget that the Spit's drag was pretty good compared to most of the other planes of the era. It wasn't particularly draggy by any means.



Actually the Spit was one of the draggiest s/e fighter planes of the era, this is why it was so short ranged... even the lowest Cd0 fgiven for Mk Vb of CD0 = 0.0213 means that the total equivalent drag of the aircraft was 5.15 sq. feet, for the for Mk IX of CD0 = 0.0238 means that the total equivalent drag of the aircraft was 5,76 sq. feet. And that's a lot.

Don't mix Cd0 with "dragginess", cd0 is usually understood as a coefficient for wing area only.


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## tomo pauk (May 22, 2013)

OldSkeptic said:


> ...
> Note: all numbers can be a bit uncertain (plus or minus a bit) as I'm reading it off charts.
> Some other interesting observations, the CD of the Spit was very similar for CL 0 to CL 0.2, while the Mustang shows significant difference.
> 
> In the high mach (0.7+) region the Spitfire was consistently better, with the gap growing as the mach rose (to 0.75 or 0.8 ).



Any chance that charts might be posted here?



> So there was nothing wrong with the Spits shape (wings, fuselage, tail) difference came from the radiator system and details. In some areas (like tail area) it was better. The wings were probably about the same, up to high mach when the Spit's wing is better. The Engine cowling and intakes were better on the Mustang (beautiful low drag front).
> 
> Details matter a lot, the flat bulletproof windscreen cost the Spit 5mph, cannons on later models cost it another 5mph. The finish of the Mustang was far better (when new), not just the tailwheel and wheel covers, but the overall fit an finish. The Mustangs radiator had very low drag in most flight regimes and the faster it went the better it was. The Spit's (and this was a Spit I) much worse, made even worse when they went to twin radiators.



Be it as it is, the completely covered wheels help Mustang too.



> Other interesting facts: The Spit used 2 types of wing section. NACA 2213 at the root, 2208 near the tip. So not only did it get thinner the further you got out and had wing twist, the section changed (I think this was to reduce wing twist drag).



The NACA 2213 should mean that wing belongs to the NACA 2200 profile, 13% thick; 2208 is, again NACA 2200 profile, 8% thick. 



Tante Ju said:


> Actually the Spit was one of the draggiest s/e fighter planes of the era, this is why it was so short ranged...



Nope, it was short ranged when carrying 85-95 gals of fuel. 



> even the lowest Cd0 fgiven for Mk Vb of CD0 = 0.0213 means that the total equivalent drag of the aircraft was 5.15 sq. feet, for the for Mk IX of CD0 = 0.0238 means that the total equivalent drag of the aircraft was 5,76 sq. feet. And that's a lot.
> 
> Don't mix Cd0 with "dragginess", cd0 is usually understood as a coefficient for wing area only.



Yes, let's not mix up stuff. 
Let's go straight to the point and say that Spitfire have had far more wing area than, say, Yak fighters, La fighters, MC fighters, Bf-109... Even the Fw-190 have had ~15% less wing area. Size matters - that's why Yak-3, MC.205 and Bf-109 were capable to make circa 650 km/h even on, for mid and late war standards, modest power. We can compare MC.202 and Re.2001, and MC.205 and Re.2005 - there was no way for Regianne to be faster than Macchi, since the Re. have had more wing wetted area. 

So we can compare Spitfire with Ki-61, Re-2001/5, G.55 and THEN come to conclusion what airplane was draggy or not. And we can also note that such planes were capable to carry multiple internal cannons and generous fuel when tasked, no problems - contrary to Yaks, Bf-109 or MC.202/5. In other words, there aint such thing as free lunch.
Almost forgot - Spitfire was also able to carry the heavy powerful Griffon, again without problems. Maybe it would be the best not to try that with small, 'undraggy' fighters?


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## drgondog (May 22, 2013)

Tante Ju said:


> Actually the Spit was one of the draggiest s/e fighter planes of the era, this is why it was so short ranged... even the lowest Cd0 fgiven for Mk Vb of CD0 = 0.0213 means that the total equivalent drag of the aircraft was 5.15 sq. feet, for the for Mk IX of CD0 = 0.0238 means that the total equivalent drag of the aircraft was 5,76 sq. feet. And that's a lot.
> 
> Don't mix Cd0 with "dragginess", cd0 is usually understood as a coefficient for wing area only.



Tante Ju - Strictly speaking CDo is the total Parasite Drag at zero lift (to remove Induced Drag component).. so it encompasses Friction Drag, Form Drag, etc - literally everything but drag due to lift (i.e wing twist, LE slats, Flaps, Wing Body lift)

Having said this, you are absolutely correct that CDo is expressed as a function of Wing Area..


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## Shortround6 (May 22, 2013)

For some real simple comparisons of drag see Spitfire vs Hurricane, Spitfire V vs P-40F.

And lets not forget that at various cruising speeds and various altitudes the Spitfire V swapped back and forth with the 109F-4 as to which used the least fuel to cover 100 miles. Not strictly drag but total propulsive efficiency and they were usually within a few % of each other. Not bad for a "big, draggy" airplane.


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## tomo pauk (May 22, 2013)

drgondog said:


> Tomo - I don't have them offhand, but the Lednicer report had the Fw 190D Flat plate Drag at 4.77 to to Spit IX 5.4 and the P-51D at 4.61. I'll have to re-check the report to see the altitude and speed that the flat plate drag was calculated.
> 
> If you have a published (reliable) flight test with GW, top speed at SL and rated Hp of the engine I can calculate it, or in the case of the Lednicer report noted above, the GW of the FW 190D for which the Drag was cited - I can extract that.
> 
> The Total Drag can be extracted from Lednicer if altitude and airspeed is say 360kts at 15000 feet - but need GW to extract Induced Drag to subtract from the Total Drag to get Parasite Drag...



Bill, maybe it would be the best to look at these fight tests, in hope nothing gets lost in translation? 

Anyway, reading from the power chart Denniss kindly posted, at sea level, on 'Start-und-Notleistung' power setting, the engine was giving 1780 PS. The D-9 was tested, according to this, 557 km/h (346 mp/h) at SL ('Start-und-Notleistung Normal' setting, the engine gaps were not sealed). The normal take off weight of the D-9 is quoted at 4270 kg (~9405 lbs) by following table.

I've partly translated part of the table, earlier kindly provided by our member Bada, seems that on high speed the A-8/9 have had some 10% greater Cd than D-9? (open the table separately for hi-res)


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## drgondog (May 22, 2013)

I will crank over the next 24 hours. Offhand the Drag numbers in that chart look awfully high. For example D-9 wing and tail parasite drag per translation (only=.1647+.0440)= .2117 which is ridiculously high (by 15x) compared to what I would expect for Zero lift parasite drag of the wing and tail


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## tomo pauk (May 22, 2013)

We might arrive at interesting numbers, with high-speed Cd divided by wing area. Ie. For the D-9, 0.444/18.9 gives 0.0234 (in the ballpark with Spit XI), and A-8/9: 0,485/18.9 gives 0.0256. Don't quote me on this - the Cw (wiederstand coeffizient - drag coefficient) actually has the measuring unit - square meter. Equivalent flat plate?? 0.444 m^2 is equal to 4.779 sq ft.
Help.

edit - Lednicer gives f values for the A and D as being 5.22 and 4.77, respectively. Fw data gives for A-8 0.485 m^2 = 5.22 sq ft. Nice 
edit2: German term is 'Wiederstandflache' (CwF) - ie. 'Drag plate'


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## drgondog (May 22, 2013)

tomo pauk said:


> We might arrive at interesting numbers, with high-speed Cd divided by wing area. Ie. For the D-9, 0.444/18.9 gives 0.0234 (in the ballpark with Spit XI), and A-8/9: 0,485/18.9 gives 0.0256. Don't quote me on this - the Cw (wiederstand coeffizient - drag coefficient) actually has the measuring unit - square meter. Equivalent flat plate?? 0.444 m^2 is equal to 4.779 sq ft.
> Help.
> 
> edit - Lednicer gives f values for the A and D as being 5.22 and 4.77, respectively. Fw data gives for A-8 0.485 m^2 = 5.22 sq ft. Nice
> edit2: German term is 'Wiederstandflache' (CwF) - ie. 'Drag plate'



D/q = Cd*S so, what we see in the rollup data is the "D/q" calculation.. and then Cd follows as Drag Force divided by Area..

which now works..D in pounds, Q in pounds/sq.ft = equivalent square feet of flat plate drag

So (D/q)/S=Cd: .444/18.9 = .002349

I wasn't familiar with the presentation but shoulda noted the "(delta W)/q *m>>2) and recognized it as 

(delta D/q) = Cd*S for each major sub component.. too used to English units rather than metric and too old to convert.

q= .5*rho*(V*V); rho = .002377 in slugs ; V*V in fps = 346*1.467*(346*1.467)= 257,639.5 Ft.sq/sec.sq
q= 306 pounds/sq.ft
CL = (W/S)/q = (9405/197)/306.2 = .1559; CL>>2 = (.1559)>>2 = .0243

CDi= (CL)>>2/(Pi*AR*e); assume 'e' = ~.85 and assume about a 5% reduction in Aspect Ratio AR due to wingtip drag.

AR= (wing span)>>2/Wing Area *(1-.05) = ((34.4>>2)/197 )* .95= 5.8

CDi= .0243/(3.14*5.8*.85)= .00157

But CD = CDo+CDi; solving for Cdo -----> = CD-CDi = .02349 - .00157 = .02192 for Zero Lift Parasite Drag via SL dash speed data.

By comparison, the 51 was around .017, the Spit IX about .023 and the 109G about .026+
=


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## tomo pauk (May 22, 2013)

Great stuff, Bill. Many thanks


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## OldSkeptic (May 22, 2013)

Tomo, The charts come from an old RAE report (got to chase it down again) and they have different scales.
I re-scaled them (and made mach adjustments),bu they are a bit of a mess.

I've been meaning to do a tidied version for ages, might do it this weekend.


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## Glider (May 22, 2013)

drgondog said:


> D/q = Cd*S so, what we see in the rollup data is the "D/q" calculation.. and then Cd follows as Drag Force divided by Area..
> 
> which now works..D in pounds, Q in pounds/sq.ft = equivalent square feet of flat plate drag
> 
> ...



11.45pm UK time is the wrong time to open a post like this and try to understand it.


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## Aozora (May 22, 2013)

Glider said:


> 11.45pm UK time is the wrong time to open a post like this and try to understand it.



Just µ over ῼ = ‰ + ® divide by 23 and the answer is 42...easy

OR


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## OldSkeptic (May 24, 2013)

OK finally got these wind tunnel stuff sorted out (sort of).
They are from RAE Report 2535 and are a combination of test on the Spit Mk1, Mustang Mk, Spiteful and Attacker (plus alternate Spiteful windscreens).

They (as the report shows) only a reasonable fit to real life test, but they key thing is that they are a constant test without distortions caused by radiator efficiency, fit and finish, etc.
Therefore they represent the theoretical results of the body/fuselage/tail.

There is a key point for the Spitfire numbers, they had made a mistake in their readings and corrections.
As the article mentions that for comparison between the Spit and all the others you have to correct the mach numbers:
_0.6 becomes 0.607, 0.7 becomes 0.712, 0.75 become 0.768, 0.78 become 0.807, 0.8 becomes 0.838._

They say that they are not reliable above mach 0.75, which explains the odd Spit results at CL 0.4

I have put the charts together and (reasonably) matched them.
Because the CL varies with mach I have done 4 charts: mach 0.4, 0.6, 0.7 and 0.75. I'll show them in separate posts
The green vertical lines correct for the Spit mach numbers. I chose to keep the Spit's ones constant and show the corresponding _adjusted_ value for the Mustang.
Blue horizontal lines are for the Mustang and red for the Spit.
The key is where the green and blue/red lines intersect.

*Mach 0.4*





As we can see the Mustang is better at mach 0.4 at CL 0. Almost identical at CL 0.2 and CL0.4.


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## OldSkeptic (May 24, 2013)

Mach 0.6






Mutang better at CL0, same at CLL 0.2 and bit worse at CL 0.4.


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## OldSkeptic (May 24, 2013)

Mach 0.7 (note the correction).





Similar picture Mustang better at 0, same at 0.2 and worse at 0.4


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## OldSkeptic (May 24, 2013)

Mach 0.75. Again note the mach correction.





Now things change. Mustang slightly better at CL 0, but now worse at Cl 0.2 and much worse at CL 0.4,


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## OldSkeptic (May 24, 2013)

Basic overall conclusions, given the levels of accuracy of the measurements and my scaling and selecting, they were very close in most flight regimes of CL and speed. Only at the extremes do any significant differences show.

Note that on my early post about this I hadn't been so systematic about the different mach speeds and tried to 'eyeball' average values.
Definitely got some wrong then.


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## zjtins (May 24, 2013)

me109 wing vs p51 info I will get the Spit info next 



> Aircraft


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## drgondog (May 24, 2013)

OldSkeptic said:


> Mach 0.75. Again note the mach correction.
> View attachment 234081
> 
> 
> Now things change. Mustang slightly better at CL 0, but now worse at Cl 0.2 and much worse at CL 0.4,



Several items interesting about the plot. Question - do you have the originals? When I look at CL=.1 for the Spit the Total Drag CD is LOWER for CL=.1 from .5M to .7M than at CL=0 which should not be the case. In all cases total Drag should be at minimum when aircraft in Zero Lift AoA... (no Induced Drag and Form Drag at minimum)

Drag = Zero Lift Parasite Drag + Induced Drag + Form Drag + Compressibility Drag. 

AT CL=0 all these plots reflect increased compressibility (which becomes meaningful above .35M).. The Spit demonstrates no compressibility drag rise (IMO because of thin wing) until the .5M region. The Spit CD rises non-linearly in the .6M to .7M where it enters Onset Drag region (i.e. region where CD increases ~ .002 over short interval of velocity). 

Note: The Spit wing had max T/c at ~25% so the velocity gradient from free .stream Vo is higher than the more gradual increase for the Mustang at ~ 45%. It will enter the Mcr profile Sooner but will ultimately have less drag at M>.85 because of the thinner wing. 

The Mustang demonstrates a steady but small increase of CD until .6M to .7M where it 'flattens out' (IMO -again the wing) and doesn't reflect onset Drag Rise until .72-.75M. 

In ALL flight velocity range @CL=0 the CD of the Mustang is lower to significantly lower ([email protected] to Spit [email protected]). This reflects reality for all reported flight tests for level flight speed runs.

At CL=0 (which could only occur for zero G dive at .7M) the real differences are significant. For CL>0 the aircraft are in positive G increasingly high angles of attack where form drag increases dramatically... hence the 'spikes' for each CL increase..

Was this a full scale wind tunnel test? The RN is curiously low.


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## tomo pauk (May 24, 2013)

In my humble opinion, the web site linked at post #154 is utter BS.


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## drgondog (May 24, 2013)

It is written by someone with a cursory knowledge of aero terms, has some facts and opinions not so well based on facts.

First - the Straight stall speed for the Mustang will occur at CL max ~1.78 to 1.89 depending on GW (w/Flaps) and the CLmax for the 51 is ~ 1.6 for level flight (depending on GW).

The CLmax for the 109 w/Flaps and LE slats is ~ 2.0 for level flight. What is not clear is what effect (trim drag for example), the extra lift for the top wing causes to require increased rudder deflection to overcome natural yaw due to the LE Slats..

What is not stated (and I believe not well understood by the author of that piece) is that the form drag (i.e. BL separation on Fuse and wings, trim drag of deflected rudder/ailerons, etc) related to high AoA flight conditions is extraordinarily high near CLmax as separation is occurring on both the wings and the fuselage. I don't have the data but I suspect that the reason that both the Spit and the P-51 competed well in turn maneuvers with the 109 was that the combined Parasite and Form Drag of the Spit/51 was lower than the 109 in high G maneuvers. Staying power in a turning (or climbing) fight is all about a.) WL and b.) Excess Thrust over Drag.

According to the author, the only reason one could surmise that the 109 got shot down in a maneuvering fight is incompetency on the part of the 109 pilot. 

I suppose zjtins has a reason to post the opinion..but that is not particularly evident from prior track record of his posts so far..Do ya suppose Gaston has returned?


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## drgondog (May 24, 2013)

OldSkeptic said:


> Basic overall conclusions, given the levels of accuracy of the measurements and my scaling and selecting, they were very close in most flight regimes of CL and speed. Only at the extremes do any significant differences show.
> 
> Note that on my early post about this I hadn't been so systematic about the different mach speeds and tried to 'eyeball' average values.
> Definitely got some wrong then.



Don't apologise - I love the charts and hope to look at the originals.. They are consistent with other P-51 Drag vs M for different CL in that the drag rise for higher CL is showing up in the .65M range as it should.


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## tomo pauk (May 24, 2013)

Bill, you are, how sould I express this... to generous for someone undeserving (ie. to the author of the web page, linked at post 154). 
The author of the page lists the 109G as a 1941 machine, capable then to do 416 mph (we need to wait for 1942 for the F4 and G-1/2 to do this). Then he claims that Spit V was able to do 400 mph, and P-51D (of 1943!) capable for 395 mph??? Range with drop tanks - 624 miles for 109G, vs. 950 miles for the P-51D?? Rate of climb - 3300 fpm 109G, 1700 fpm P-51D - every time now I'll run out from question marks...
That is from Comparison chart #2, the chart #1 is nowhere to be seen. However, the chart #2 is actually a table.
The caption under a picture there says:



> The P-51 Mustang and the Spitfire are often thought of as the mightiest fighters of WWII. They were not. The Me109 was and here are some of its secrets! The SECRET of the Messerschmitt Me109G!



What a source.


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## zjtins (May 24, 2013)

So much for a near current pilot flying both planes... he must be a liar.


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## Glider (May 24, 2013)

Maybe just a bad memory. Note two examples

1 Some German aces such as Hans Joachim Marseille shot down 17 English *Spitfires *in one day (8 were in 10 minutes) in his Bf109
2 The max speed of a SPit V 400mph and the P51D 395 mph


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## drgondog (May 24, 2013)

LOL - Tomo, I was only dealing with the small part that was fact. The pilot in the youtube video owns a 109 and certainly entitled to his opinion.. wish he could have demonstrated his skill against my father or Henry brown or Preddy or name 500 others flying a P-51D or B or Spit IX..

My numbers after looking at 6000+ 8th AF encounter reports suggest the number of credited 109s shot down by 8th AF was ~ 2519 Bf 109s, then 1964 Fw 190s (out of total 5169 all types) for loss in the air of ~ 640 P-47/P-38/P51/Spits. 

Of course I can't get a handle on losses due *only* to 109s but if 100% that would be 2519/640 =3.9:1.........


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## drgondog (May 24, 2013)

zjtins said:


> So much for a near current pilot flying both planes... he must be a liar.



Nah - merely a.) factually correct on CLmax, a.) misinformed about both stick forces at high speed for roll and turn for the P-51 and Spit , b.) incorrect about performance statistics for the models he cited and c.) entitled to his opinion.

He would have to cite his direct experience in air combat maneuvers versus a similar minded equal skill pilot in a well restored P-51D and Spit IX against his 109, and both the other pilots willing to push their Merlins to limits often used in WWII air combat (~67" or greater depending on fuel) - for his Personal experience to be relevant. Offhand I don't know any warbird pilots willing to risk their $3M+ birds to do this... but I'm willing to bet Yeager at his advanced age could whip his ass.

Forget about him being a liar.. consider the possibility that the person that keeps blowing chaff in this thread with zero to minimal facts to base his Tourette's syndrome blurts is a moron.


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## drgondog (May 24, 2013)

PS - I may be a moron also.. so don't take the comment to heart.


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## tomo pauk (May 24, 2013)

zjtins said:


> So much for a near current pilot flying both planes... he must be a liar.



Didn't say a word about the pilot. 
The data, or 'data', listed in the table named chart 2 is flat wrong, and whole article is trumpeting about just how ideal the 109 was. 



> Glider said:
> 
> 
> > Maybe just a bad memory. Note two examples
> ...



I don't believe it's a case of bad memory. Complete data in the table is wrong, speed, RoC, range, year of introduction. The Bf-109 ends up as a champion.

Hi, Bill,


> I suppose zjtins has a reason to post the opinion..but that is not particularly evident from prior track record of his posts so far..Do ya suppose Gaston has returned?



I can understand zjtins - he was looking at sources to back up his claim, and posted a link to the one he found fit; doing that, I believe, in good faith. Gaston's posts are way more voluminous, though.


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## zjtins (May 24, 2013)

So no-one watched the video??? He has both planes (ME109 and P52D) and flies them.
So the author of the page misquoted of typo' what about the pilot of the two aircraft?


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## fastmongrel (May 24, 2013)

drgondog said:


> I suppose zjtins has a reason to post the opinion..but that is not particularly evident from prior track record of his posts so far..Do ya suppose Gaston has returned?



I assumed from the bad grammar, worse spelling and inability to face facts zjitins was the lastest sockpuppet of Shooter. Also known as Stewart Davies who was a Porsche works driver, a Vietnam special forces veteran, black ops deep cover agent, a tank warfare instructor in the German Army, a medal winning shooter and a Star Wars X Wing fighter pilot. Oh and Shooter is also principal of a college in Illinois busy chap aint he.


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## drgondog (May 24, 2013)

zjtins said:


> So no-one watched the video??? He has both planes (ME109 and P52D) and flies them.
> So the author of the page misquoted of typo' what about the pilot of the two aircraft?



The gent would have to fly both - at the same time - or fly his 109 against another pilot in a Spit and/or P-51D.. 

Here is what YOU don't know. In What condition (airframe and engine and control harmony) are the aircraft that he flies. What are the respective GW of the aircraft when he compares performance, what boost is he using in the comparison... how is the engagement 'tested' relative to turn G's, etc.

I henceforth dub you sockpuppet moronis and banish you to using words of one syllable or less.


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## nuuumannn (May 24, 2013)

Huh?



> One of the secrets of the Me109 is its wing. A unique design like no other.



"I was particularly interested in the operation of the slats. the action of which gave rise to aileron snatching in any high-g manoeuvres, such as loops or tight turns."

"A number of dummy attacks on a co-operative Lancaster and a friendly skirmish with a Mustang flown by one of the RAE pilots revealed the fact that the slipstream of these aircraft caused the intermittent operation of the Bf 109G's slats so that accurate sighting became an impossibility."

"At its rather disappointing low level cruise speed of 240 mph (386 km/h) the Gustav was certainly delightful to fly, but this situation changed as speed increased; in a dive at 400 mph (644 km/h) the controls felt as though they had seized!"



> With the same power in the Me109 and an empty weight of 1,700 lbs. less, the climb rate of the Me109 was substantially higher than that of the P-51. Because of the fantastic handling characteristics of the Me109, the P-51 was not match for the Me109.



"The Mustang III possessed a clear speed advantage at all altitudes, this ranging from around 30 mph (48 km/h) at the Bf 109G-6's rated altitude to some 50 mph (80 km/h) at 30,000 ft (9 144 m). The Gustav offered marginally better climb rate up to 20,000 ft (6 096 m) but between this altitude and 25,000 ft (7 620 m) the Mustang had a very slight advantage. When dived and then pulled up into a climb there was little to choose between the US and the German fighter, but the Mustang could steadily out dive the Bf 109G-6 and had no difficulty in out turning the Messerschmitt."



> The performance of the Me109 and the Spitfire is almost the same. However, the Spitfire had an average 25%C plain aileron which, despite differential control, gave it a very heavy stick force in roll compared to the light stick force of the Me109.



"The Air Fighter Development Squadron flew the Bf 109G-6 for tactical trials with a Spitfire LF IX, a Spitfire XIV and a Mustang III (P-51C) and found thast the first mentioned type had a slight speed advantage up to 16,000 ft (4 877 m) when using 18 lb (8.16 kg) boost, but the situation being reversed between this altitude and 20,000 ft (6 096 m) at which the Spitfre LF IX regained the speed advantage to the extent of some 7 mph (11 km/h). Using 25 lb (11.3 kg) of boost the Spitfire proved to be about 25 mph (40 km/h) faster below 15,000 ft (4,570 m) and around 7 mph (11 km/h) faster above this altitude, which climb was superior to that of the Gustav at all altitudes and particularly below 13,000 ft (3 960 m). The Bf 109G could leave the Spitfire LF IX behind in a dive without any difficulty, but when both aircraft were pulled up into a climb from a dive their performance was almost identical, the Spitfire slowly pulling away as soon as climbing speed was attained."



> With a 50% span and narrow chord, Frise, aileron, the Me109 stick forces were very low in roll and it could roll quicker and was more evasive than the Spitfire which was slow in roll.



"The rolll rate and turning circle of the British fighter was very much superior at all speeds."



> The control harmony of the Me109 could not be matched by any Allied aircraft in WWII.



"Control harmony was poor for a fighter, the rudder being light, the ailerons moderately light and the elevators extremely heavy."

Information courtesy of Eric Brown from Wings of the Luftwaffe.


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## DerAdlerIstGelandet (May 25, 2013)

Lets stop with the personal insults and attacks.

Only warning given...


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## Aozora (May 25, 2013)

Aircraft
Gotta love this quote:



> The Me109 had a long tail moment arm and the rudder was 50%C. As such it could be yawed from right to left by 45 degrees to spray bullets. The P-51 could not be yawed and had to be flown at the target for its bullets to hit the target.



I can just see fighter pilots being trained to _*spray*_ their bullets at 45° either side of the flight line.  Would love to see this guy in combat...  




> Some German aces such as Hans Joachim Marseille shot down 17 English Spitfires in one day (8 were in 10 minutes) in his Bf109.



Yet, a glance at Hans-Joachim Marseille - Wikipedia1 September 1942 shows Marseille claimed mostly Hurricanes and Tomahawks and Kittyhawks with just one Spitfire.

Oh yes, this website should be a standard reference for all 109 enthusiasts.


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## Shortround6 (May 25, 2013)

I kind of liked this sentence;

"One of the secrets of the Me109 is its wing. A unique design like no other."

Since Me was licencing the slats from Handley Page and quite a number of British Planes ( and few other countries) used leading edge slats this statement needs a bit of backing up. 

Or more than a bit.


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## drgondog (May 25, 2013)

The elderly 'interviewer' in the 109 YouTube clip was pretty clueless across the board.. there isn't enough space to detail what he didn't know or have facts to support. 

As to the wing - it was a nice design, strong, detachable easily for transport, light and the LE slats offered low speed increase to CL without sacrifice of higher induced drag with 'normal' washout/wing twist. Can't think of one single uniqueness or patentable idea.

In addition, the CD of the Bf 109 was about 50-60% higher than the P-51 which contributed to the necessity of requiring a major and continuous upgrade of Hp to keep the 109 reasonably current with respect to airspeed but as a result suffered increasing handling quality degradation due to the torque combined with no major tail increase authority until the K.

The knucklehead completely dismissed the huge advantage in speed and roll at medium and high speeds the P-51 had when the P-51B entered combat against the Bf 109G-5 and G-6.. and somehow even a couple of hundred feet per minute better climb rate doesn't seem as important when your adversary is on your tail...


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## bbear (May 26, 2013)

forgive a dufus for dragging the topic into the conversation, but aren't we overlooking something? or at least not weighing it much - extending range was tried by Supermarine all the way from Dunkirk until at least the Mk V?

Mk IIa got a 40 imp gallon external tank introduced about the beginning of 1941 (penalty 26 mph in top speed (I have one poor secondary reference)
Mk III got 2 x 30 imp gallon wing tank option from the get go IIRC
Mk V had a range of external tankage options up to 170 imp gallon blister (drag penalty 35 lb at 100ft/sec 
From Morgan and Shacklady) the latter tankage option could get you to Berlin on a 'reinforcement' escort sortie with minimal time over target for actual fighting (and probably worse performance in every other way. And the V was a stop gap... )
Mk IX was a higher power and I'm not sure ...


so if that's logical or agreed or even roughly right then...
maybe this thread would need not one solution, for the best last griffon powered Spitty for example, but as many as 4, 5, or 6 different solutions from October 1940 until April/May 1944 - one for each mark and another for each major variant if necessary. 

I am impressed by the huge knowledge on display. But isn't analysis of the original solution necessary before jumping into a design war? Might attention to the original effort even limit the time taken to get something agreed? Personally I'd like to hear reasons with each proposal why it is better than the original modification in service, not better than the base spec. That or reasons why 20-20 hindsight shows that 'one size fits all'

(Did I say 'agreed'? I, of course, meant not disputed with the last fibre of the being. Ready to run for cover again... apologies if it's nonsense)

(I say October 1940 to April/May 1944 as I believe that's roughly when the RAF went on first significant post BoB fighter offensive operations to the time when the bulk of escort P51 equipped squadrons had actually entered regular escort ops with their new equipment as far as I can tell, ie i'm quickly guessing the earliest and latest relevant reasonable date, assuming the need for range was identified in May 1940 directly after Dunkirk - but it is a rough guess aimed to limit the area for disagreement)


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## Shortround6 (May 26, 2013)

Part of the Spitfire's _legend_ and also part of it's _curse_ was that Smith Company could usually bodge together some sort of short term solution to a new problem that *did not* require screwing up the production lines too much and causing too great delay in deliveries. Unfortunately this demand for few and/or short delays meant that more extensive revisions were often sidelined. 

For instance the MK VIII had the leading edge tanks. But I believe (and could very well be wrong) that the MK VIIIs came from one factory and the other producers stayed with the wing without leading edge tanks (the MK IX) rather than convert so as to avoid a disruption in production ( and everybody _knew_ that you couldn't make a long range single engine fighter ). Perhaps more could have been done with rear fuselage tanks by moving some equipment about, strengthening a few parts, moving the engine forward just a bit ( for CG reasons) but all would require both engineering time and some retooling (lost production).

The Spitfire got very few well thought out, total make overs considering it's long history. The Mustang got 2, Allison to Merlin and the D to H. the 109 got 2 or 3( jumo 210 to DB 601, E to F, and G to K ?) The Spitfire is 4 years older than the P-51 and had to wait to the MK 21 for a really extensive make over. Granted it was pretty well stretched by that time


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## Glider (May 26, 2013)

Shortround6 said:


> The Spitfire got very few well thought out, total make overs considering it's long history. The Mustang got 2, Allison to Merlin and the D to H. the 109 got 2 or 3( jumo 210 to DB 601, E to F, and G to K ?) The Spitfire is 4 years older than the P-51 and had to wait to the MK 21 for a really extensive make over. Granted it was pretty well stretched by that time


Shows the benefit of getting it right from the start


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## bbear (May 26, 2013)

Gently does it.

by getting it right from the start you mean either
a) the right approach is to give the original designers a spec including every possible use of a/c- use of crystal ball comes extra
- or 
b) don't build a spitfire because elliptical wings are _wrong_ - gently does it.
or 
c) an implied nod to the circumstantial limitations of the design problem that won't start another riot
or 
d) be lucky, start late and design a P51

I think it's c) - just a guess


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## nuuumannn (May 26, 2013)

> I think it's c) - just a guess



I agree with Glider; the Spitty's designers did get it right - the changes that were made whilst retaining the centre fuselage demonstrates the brilliance of the design. It was designed with a certain amount of growth potential in it; it's interesting to note that the most mass produced variants were intended as temporary expedients, which were models already in production but were fitted with uprated engines; the V, IX and XIV. The fact that there was little change between the fuselage between Frames 5 and 19 throughout almost every mark of Spitfire proves its genius. New wings, tail section, armament, undercarriage, powerplant mated to the same design of fuse was pretty impressive. Of course the designers couldn't have foreseen the actual growth of the aircraft, but its growth potential was no accident.


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## Glider (May 26, 2013)

bbear said:


> Gently does it.
> 
> by getting it right from the start you mean either
> a) the right approach is to give the original designers a spec including every possible use of a/c- use of crystal ball comes extra
> ...



A ish. Build an aircraft pre war, that has the ability to stay in the front line, be second to none (apart from range) in its primary role, be flexible enough to be a contender as good as the best in other roles (Thinking PR), carry a decent payload in the GA role, and even be of use on a carrier (alright would you settle for just about good enough as a carrier plane). All without a major redesign.
Nearest is the 109 which you pointed out had a major redesign with the F and never had the flexibility of the Spit.

Nearest US aircraft would be, erm, let me think, err nope cannot think of one. P38 was closest but was later, didn't serve on a carrier, and wasn't as good as a PR aircraft.


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## nuuumannn (May 26, 2013)

To be fair to the US aircraft designers, there were a large number of firms building aircraft for specific roles that the likes of the multi-role single airframe, such as the Mosquito or the Spitty rarely appeared. The fact that the likes of the P-38, P-47, B-25 et al were adapted for different roles outside of their original spec is indicative of the versatility of the types, but there was rarely a need to adapt an 'Army' aircraft for a carrier role, for example. The Seafire and Sea Hurricane were expedients brought about by a lack of a suitable modern British aeroplane for the role, rather than a conscious decision based on the versatility of each type.


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## drgondog (May 26, 2013)

Glider said:


> A ish. Build an aircraft pre war, that has the ability to stay in the front line, be second to none (apart from range) in its primary role, be flexible enough to be a contender as good as the best in other roles (Thinking PR), carry a decent payload in the GA role, and even be of use on a carrier (alright would you settle for just about good enough as a carrier plane). All without a major redesign.
> Nearest is the 109 which you pointed out had a major redesign with the F and never had the flexibility of the Spit.
> 
> Nearest US aircraft would be, erm, let me think, err nope cannot think of one. P38 was closest but was later, didn't serve on a carrier, and wasn't as good as a PR aircraft.



Maybe F4U was closer?


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## Glider (May 26, 2013)

Have to say thats a good choice, an aircraft that served for many years without a fundamental change in its design. The only thing that I would say is that its introduction into service was a few years later than the Spitfire. However you are right it is a good contender


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## zjtins (May 29, 2013)

> I can just see fighter pilots being trained to spray their bullets at 45° either side of the flight line. Would love to see this guy in combat...


The 45 degrees is probably moot, but the jist of it was the US/British fighters were difficult to line up a shot with rudder relative to the ME109. So in a dogfight the ME109 had an advantage of enabling in the pilot to chose to use rudder control for fine tuning his shot, the allied planes resorted to mostly to stick only. I have seen this comment by several pilots including non-Germans. So apparently those pilot st least felt this was worth mentioning. And no I do not have any analysis to back this up just commentary from several pilot interviews.

There are clips of German attack on bombers where yes they actually rake the bombers side to side in plane so that appears to be rudder control.


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## drgondog (May 29, 2013)

Where in the world do you dream this stuff up? Using rudder in a co-ordinated way with ailerons is second nature to even an average pilot - If you ski it is the difference between a stem Christie and a carved turn.


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## zjtins (May 29, 2013)

> Where in the world do you dream this stuff up? Using rudder in a co-ordinated way with ailerons is second nature to even an average pilot - If you ski it is the difference between a stem Christie and a carved turn.



Go watch Ralls comments on youtube (from military channel or discovery not sure which) to start. Then search for ME109 pilot bios or interviews.
These are NOT coordinated turns, no watching the ball. They are flat side to side movement to move the streams of rounds across an aircraft.


Again go watch the clips there are many on youtube, easy to find.


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## FLYBOYJ (May 29, 2013)

zjtins said:


> There are clips of German attack on bombers where yes they actually rake the bombers side to side in plane so that appears to be rudder control.



Another moronic comment from an armchair pilot...


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## drgondog (May 29, 2013)

zjtins said:


> Go watch Ralls comments on youtube (from military channel or discovery not sure which) to start. Then search for ME109 pilot bios or interviews.
> These are NOT coordinated turns, no watching the ball. They are flat side to side movement to move the streams of rounds across an aircraft.
> 
> *WATCHING THE BALL??????? They ain't flying instruments.. they are watching the target and instinctive feet and stick are keeping the evading target in the gunsight ring...*
> ...



I have approximately 60 hours of 8th AF gun camera film and one hour of LW film - pretty familiar with the concept. If You, on the other hand with your vast knowledge of LW tactics against bombers or fighters, look at them more closely you will note for example:

When close in - say on a B-17, the pilot is usually firing a package of 20mm into one engine, then moving to a second, then fuselage and maybe a third as contrast with 'spraying'.. against a fighter at 6 O'clock he's not moving wingtip to wingtip by choice - the fuselage, cockpit and engine are the key - not the wing per se.

If the target is flying straight and level, there is nor reason for aileron adjustment (Hand for you) other than to stabilize in wake turbulence - there you only need some rudder (feet for you) control.. to regain target acquisition.


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## OldSkeptic (Jul 25, 2013)

Just been doing some re-reading recently.

It's amazing the impact one person can have, from the moment he became CAS (head of the RAF) Portal endlessly fought against a long range fighter.
His attitude was that it was impossible to make and given his position he made sure it never happened.

But even I didn't know (until some reading recently) how hard he fought against it. He had a running battle withe USAAF right through 1943 repeatedly telling them that it 'was impossible'. Did so even when the USAAF flew a couple of modified Spits across the Atlantic (plus all the prototypes and test done by the RAF itself) as a demonstration and were literally begging the RAF to help out.

Kept it up right until (for example advising Churchill even as late as Oct 43 that 'it was impossible') the P-51B came into service (even though he must have known that it was in preparation and about the much earlier the Mustang X trials).

Only then did he finally shut up.

The damage that one man created by his idiotic obstinacy. He was so adamant about it and so tirelessly worked to make sure it didn't happen that he was even soundly criticised about it in the official RAF history of WW2. 

Makes me wonder who was really responsible for the incredible reluctance to use night fighter intruders for BC support (and how little resources were put into it until very, very late on). I always thought it was Harris, but now I wonder if it came from Portal himself (the record on this is very murky).

It was a bad day when they got rid of Dowding, he (and his number 2 Evill) had gotten R&D work done on longer ranged Spits in early 1940 even pre the BoB .... all cancelled when Douglas and Mallery took over of course and especially when Portal took over the 41. 

The RAF by and large gets a good write up over WW2, but when you read the details you can't help but notice that they had a real lot of dunderheads in the senior levels, with a real bit of the WW1 'over the top chaps and run right towards that machine gun ' attitude in far too many areas.


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## riacrato (Jul 25, 2013)

Well he wasn't alone. Messerschmitt was also of the opinion that a single engined fighter can't be long ranged until the Mustangs appeared over Greater Germany. I guess a lot of people underestimated the effects drag has on _range_ not only speed.


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## Hop (Jul 25, 2013)

The USAAF reached the same conclusion in 1940/41 as well. Spaatz wrote in the mid 30s that any fighter with sufficient fuel for long range escort wouldn't be able to cope with short range defensive fighters at the target.

I think it's a bit unfair to blame Portal. Eaker was still maintaining the line that US heavy bombers wouldn't need escort until June 1943. In August 1943 the USAAF sent representatives to Lockheed, Republic and North American to request extra fuel tanks be fitted to their fighters. It took Republic until spring 1944 to modify the P-47, NA had a simpler solution of fitting a rear fuselage tank. It wasn't until Feb 1944 that the 2 Spitfires were sent to the US for trials with more fuel.

When Vandenberg and Spaatz ruled out fitting bombs and drop tanks to the P-39, the memorandum said they would:



> provide opportunities for improper tactical use of pursuit types.



Portal also had more to think about than the purely technical aspect of fitting more fuel to the Spitfire. Until the US effort really got going in late 1943 he didn't have enough fighters to carry out a long range deep penetration campaign against Germany. From the summer of 1943 onwards he had preparing for an invasion as his priority. Apart from the possible delays to production caused by modifying fighters to carry more fuel, Portal must have been concerned that his fighters would have been diverted to supporting US bombing to the detriment of UK defences and tactical operations over France and the Med.


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## tomo pauk (Jul 25, 2013)

Hi, Hop,



> When Vandenberg and Spaatz ruled out fitting bombs and drop tanks to the P-39, the memorandum said they would:
> 
> _provide opportunities for improper tactical use of pursuit types_



What would be the date of the memorandum?


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## CobberKane (Jul 25, 2013)

Maybe the F4U's climb rate might have worked against it in the Spitfire's primary role; as a short range interceptor. I believe that's one area where the Seafire found a niche in the PTO, though it's assignment to the task probably also arose from the realisation that the Corsair and Hellcat did everything else better.


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## OldSkeptic (Jul 25, 2013)

riacrato said:


> Well he wasn't alone. Messerschmitt was also of the opinion that a single engined fighter can't be long ranged until the Mustangs appeared over Greater Germany. I guess a lot of people underestimated the effects drag has on _range_ not only speed.



None of them took into account the simple fact that the LR fighter burns off most of its fuel getting to the combat area, returning it to a normal fighter again.
Even the Mustang was a total pig fully fueled up with drop tanks on, but by the time it took to get to its escort rendezvous it was back to normal.

You use a layered escort pattern with SR fighters, MR and then LR ones all rendezvousing at different points (which can be the same type of plane with different fuel loads of course).

What matters is how much fuel you have for combat and return (after you have burned off the rear and dropped your drop tanks) and being able to have it without impacting performance.
For a Spit that meant you had full fuel (front and wing tanks) of 122 (UK) gals when combat starts, using the rear and drop tanks for cruise to rendezvous and the escort period. 
More than enough for combat and cruise to return on a 500 mile range mission.

They had plenty of Spits (roughly) 60+ squadrons with very high production. 
And there were more than enough to throw away 1,000+ of them in Leigh Mallery's 'leaning towards the enemy strategy' during 41 and 42.
And that really shows the dunder headedness, the 'plan' to hammer the Luftwaffe and make them draw more forces to France could only be achieved if there were MR and LR Spits, otherwise the Germans simply pulled their bases out of range and only engaged the RAF when it tactically suited them and inflicted tremendous losses. Note that this was also at a time when they were screaming for Spits in North Africa and Malta.....

Modifying the Spit was pretty easy, wing leading edge bags (as per the Mk VIII) and a rear tank. Even with just (say) a 30 gal rear tank (or under the seat as per some PR versions) and the wing ones you have an easy combat radius of 300 miles. Larger rear tank (only really possible in Merlin 60 series Spits) and a 90 gal drop tank and Berlin is within range (all gals are UK ones).


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## Hop (Jul 25, 2013)

> What would be the date of the memorandum?


10 March 1941 according to Davis. 



> None of them took into account the simple fact that the LR fighter burns off most of its fuel getting to the combat area, returning it to a normal fighter again.



Which suggests the opposition need to intercept early in the flight. For the Germans this would have been over the coast of France/Belgium/Netherlands, when the long range fighter is still loaded down with excess fuel. RAF fighter cover meant that wasn't a good idea. But if the RAF fighters were the long range escorts, then the obvious tactic for the Germans would have been to intercept over the coast, forcing the fighters to drop external fuel tanks, making it impossible for them to escort all the way to the target. The Germans can then have another go at the now unescorted bombers over Germany, and a third go at them as they fly back via France.

The daylight bomber offensive required the sort of numbers of fighters that weren't really available until the end of 1943 anyway.


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## OldSkeptic (Jul 26, 2013)

Hop said:


> Portal also had more to think about than the purely technical aspect of fitting more fuel to the Spitfire. Until the US effort really got going in late 1943 he didn't have enough fighters to carry out a long range deep penetration campaign against Germany. From the summer of 1943 onwards he had preparing for an invasion as his priority. Apart from the possible delays to production caused by modifying fighters to carry more fuel, Portal must have been concerned that his fighters would have been diverted to supporting US bombing to the detriment of UK defences and tactical operations over France and the Med.



The RAF had 50 squadrons of Spitfire in June 42 (nearly all MK Vs, few MK IIs, bit later some Mk IXs), they were producing 350 fighter pilots a month (and planes). They were facing just JG 2 and 26 in France (from memory). 
They had such an overwhelming numerical advantage that they could have given each Spit pilot a club, ordered them to fly over the the airfields, bail out over them (or land) ... and club every Luftwaffe pilot to death.

There was no need to worry about defences, the Luftwaffe never did any further daylight operations of any note and RV Jones promised that he would give 6 weeks notice of any new (and night, hence the Spits would be useless) bombing campaign.

They already starved the ME (inc Malta) anyway, N.A. only got Spits (2 squadrons whoopie do) at the end of '42. And Malta (again from memory) only got 4 squadrons.
So they had all those Spits sitting around with the pilots twiddling their thumbs (except those that Leigh Mallory threw away of course).
That 50 squadrons excluded the NA and Malta ones.

Slap a 30 gal tank in the rear, fix a bob weight to the elevator circuit, hang a 45 gal drop tank and send them right over the Luftwaffe's airfields. Escort bombers right to them if they still don't come up to fight.
4 weeks tops and there are no Luftwaffe fighters left in France, so then go after bomber, recon and anti-shipping airfields and planes.
Another 4 weeks and there is Luftwaffe in France at all.

RAF bombers can then go at will and in daylight against any targets that supply the Germans.

Repeat for Belgium and the Netherlands.

The thing to note is that by making an incorrect assumption ... and sticking to it despite all the evidence ... they strategically and tactically neutered themselves.
With even just a 300 mile combat radius for Spit Vs then they increased all their options tremendously (everywhere, N.A. and Malta too).
With 500 mile MK VIIIs and IXs then they have real options to grind the Luftwaffe to death and actually do some useful bombing (not something that happened much in 42).

The Luftwaffe never got much above 1,000 fighters at any point. Even when they increased production they couldn't supply the pilots and attrition meant that their operational numbers basically stayed constant.

With the RAF being able to clear France, Belgium, etc in the air meant that the Luftwaffe would have had to bring fighters back from the eastern front (etc), creating a battle of attrition which the Luftwaffe could not win.


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## Glider (Jul 26, 2013)

At Malta they added two 45 gallon droptanks from Hurricanes under the fueslage to give some long range escort to the Malta Convoys. I don't know what the actual range was but it must have helped and shows what could be done if people are allowed to try.


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## Balljoint (Jul 26, 2013)

Hop said:


> Portal also had more to think about than the purely technical aspect of fitting more fuel to the Spitfire. Until the US effort really got going in late 1943 he didn't have enough fighters to carry out a long range deep penetration campaign against Germany. From the summer of 1943 onwards he had preparing for an invasion as his priority. Apart from the possible delays to production caused by modifying fighters to carry more fuel, Portal must have been concerned that his fighters would have been diverted to supporting US bombing to the detriment of UK defences and tactical operations over France and the Med.


Actually, the US strategic bombing was subordinated to gaining the air superiority required for the invasion. Once the long range fighters were brought to bear the LW over France was obliterated in less than six months which, it would seem, was also the best UK defense.


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## Edgar Brooks (Jul 28, 2013)

OldSkeptic said:


> The RAF had 50 squadrons of Spitfire in June 42 (nearly all MK Vs, few MK IIs, bit later some Mk IXs), they were producing 350 fighter pilots a month (and planes). They were facing just JG 2 and 26 in France (from memory).
> They had such an overwhelming numerical advantage that they could have given each Spit pilot a club, ordered them to fly over the the airfields, bail out over them (or land) ... and club every Luftwaffe pilot to death.


Hoping, of course, that they managed to avoid the flak on the way.


> There was no need to worry about defences, the Luftwaffe never did any further daylight operations of any note and RV Jones promised that he would give 6 weeks notice of any new (and night, hence the Spits would be useless) bombing campaign.


And they were well aware that the Germans weren't going to attack, again? They knew, in advance, that Russia was not going to be defeated, and that the planned four-engine bombers (which were expected) were never going to happen? Really? It's a shame you weren't there to soothe their fears, and set them straight. I think you'll find that the inhabitants of Plymouth, Portsmouth, Liverpool, Hull, Southampton, London, Birmingham, Exeter, Glasgow, Belfast, and sundry other towns, didn't feel there was no need for any defences, when they were getting killed every other night.


> They already starved the ME (inc Malta) anyway, N.A. only got Spits (2 squadrons whoopie do) at the end of '42. And Malta (again from memory) only got 4 squadrons.


So the Hurricanes and P-40s, which were sent, didn't amount to a can of beans; I'm sure the pilots will appreciate being written off so easily. I take it you don't know how difficult it was to conjure up a filter suitable for desert use? Eisenhower asked for Spitfire IXs, to cover "Torch," but couldn't have them, due to inadequate filters.


> Slap a 30 gal tank in the rear, fix a bob weight to the elevator circuit, hang a 45 gal drop tank and send them right over the Luftwaffe's airfields. Escort bombers right to them if they still don't come up to fight.


Easy in theory, but not in practice; read the Spitfire V manual, and you'll find it mandatory that the extra fuel tank could only be used in conjunction with the 90-gallon ferry tank. There was also no direct fuel line from the tank to the engine (pilots weren't too keen on sharing the cockpit with fuel, for some reason,) so the fuel must go through the ferry tank, and be used first. If the aircraft was jumped, and jettisoned the fuel tank, there was no means to dispose of any fuel remaining in the rear tank, which meant that, as the fuel drained out of the front tanks, the aircraft became progressively less stable, and impossible to control. This love of the bob-weight is interesting, since experienced pilots didn't like it, due to loss of manoeuvrability, and Mike Crosley was of the opinion that it killed more pilots than it saved, since, when a pilot inverted the aircraft to abandon it, the weight worked in the opposite sense, and slammed the elevators hard up, giving the pilot no chance to get out.


> The thing to note is that by making an incorrect assumption


Which is what you're doing.


> The Luftwaffe never got much above 1,000 fighters at any point. Even when they increased production they couldn't supply the pilots and attrition meant that their operational numbers basically stayed constant.
> With the RAF being able to clear France, Belgium, etc in the air meant that the Luftwaffe would have had to bring fighters back from the eastern front (etc), creating a battle of attrition which the Luftwaffe could not win.


All of which employs 20:20 hindsight, and wasn't known at the time.
Even the Mk.IX couldn't have a rear fuel tank fitted, without major modifications, and it was the end of 1942 before they could make the trip from Gibraltar non-stop to Malta. Incidentally, as for Malta being "starved," 431 Spitfires arrived there, between March and October, 1942. 
I'm sure, too, that those pilots who went as far as they could, to meet, and escort home USAAF bombers, will be pleased to know they were just "twiddling their thumbs."


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## RCAFson (Jul 28, 2013)

According to Malta Spitfire Aces, the first direct Spitfire flight from Gibraltar to Malta was Oct 25 1942, using a 170 DT and a 29 gallon internal tank, behind the cockpit.


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## Hop (Jul 28, 2013)

> The RAF had 50 squadrons of Spitfire in June 42 (nearly all MK Vs, few MK IIs, bit later some Mk IXs), they were producing 350 fighter pilots a month (and planes). They were facing just JG 2 and 26 in France (from memory).



There was also JG 1 in the Netherlands, various other units seem to have helped out as and when. They were also well supplied and equipped.

Hooton gives sortie totals for Luftflotte 3. In June 1942 they managed over 3,500 fighter sorties, in August over 4,000. To put that in perspective, Luftflotte Reich managed 3,300 fighter sorties in January 1944, 4,500 in April 1944. 

Spitfire fighter production was around 3,800 in 1942. Hurricanes weren't up to fighter combat over Europe, Typhoons were few in number and not properly sorted for combat. The Germans produced about 4,500 109s and 190s in 1942.



> There was no need to worry about defences, the Luftwaffe never did any further daylight operations of any note



There were a lot of tip and run raids, anti shipping strikes and recce flights. The RAF had to maintain fighters the length and breadth of the UK.



> They already starved the ME (inc Malta) anyway, N.A. only got Spits (2 squadrons whoopie do) at the end of '42. And Malta (again from memory) only got 4 squadrons.



385 Spitfires were flown to Malta between March and early October 1942.



> Slap a 30 gal tank in the rear, fix a bob weight to the elevator circuit, hang a 45 gal drop tank and send them right over the Luftwaffe's airfields. Escort bombers right to them if they still don't come up to fight.
> 4 weeks tops and there are no Luftwaffe fighters left in France, so then go after bomber, recon and anti-shipping airfields and planes.
> Another 4 weeks and there is Luftwaffe in France at all.



That sounds like what the Luftwaffe tried in the BoB. Grass airfields do not make good bombing targets. Especially when there are very large numbers of them, mostly empty.



> With 500 mile MK VIIIs and IXs then they have real options to grind the Luftwaffe to death and actually do some useful bombing (not something that happened much in 42).



The Spitfire VIII didn't really come along until 1943. The Spitfire IX would have required modifications to increase the range, and at that time _more_ Spitfires were much more important than _better_ Spitfires. Look at those production figures again.

The numbers just aren't there. The Luftwaffe had numerical superiority and were just off the British coast in 1940 and still lost. The RAF had numerical superiority but were hundreds of miles from Germany in 1942. They didn't have enough planes to make deep penetration raids work. In fact, they only had enough to contest airspace over France, not drive the Luftwaffe from the skies, even within the range they did have.



> With the RAF being able to clear France, Belgium, etc



How can they clear the whole of France and Belgium etc when they didn't have enough aircraft to clear the much smaller areas they had range for? 

The numbers just aren't there. A long range daylight bombing campaign requires a superiority of force that the RAF didn't posses in 1942, or even the first half of 1943.


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## Edgar Brooks (Jul 28, 2013)

RCAFson said:


> According to Malta Spitfire Aces, the first direct Spitfire flight from Gibraltar to Malta was Oct 25 1942, using a 170 DT and a 29 gallon internal tank, behind the cockpit.


Finger trouble; hit 3 instead of 2, sorry.


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## stona (Jul 29, 2013)

Referring back to the pros and cons of the "elliptical" wing, Shenstone wrote that one of the biggest advantages of the shape was unforeseen.

“…the real advantage of the elliptical wing turned out to be its low induced drag at very high altitudes, such altitudes not having been considered during the design, but realised during the war, helping to keep Spitfire in the front line during rapid development under Joe Smith. The point here is that at great altitudes where the air is thin, the angle of incidence must be increased, resulting in more induced drag. The elliptical wing then becomes important - assuming subsonic flight.”

Cheers

Steve


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## Tante Ju (Jul 29, 2013)

How does elliptic planform reduce induced drag? I have not seen any glider with elliptic wings, all seems to have very high aspect ratio trapezoid wings. See also Ta 152.


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## stona (Jul 29, 2013)

You'd need to ask someone like Beverley Shenstone MASC, FRAES, FAIAA, FCASI.
Shenstone started his career at Toronto University where he became the first graduate to be made a Master of Applied Science in Aeronautical Engineering. He worked briefly at the Air Ministry's research laboratory in London before moving to Germany, working with Lippisch (with whom he remained firm friends for the rest of his life). He worked for Junkers in the 1920s. He returned to Britain in 1931 joining Vickers Supermarine throughout the war. He became BEA's chief engineer from 1948 before becoming BOAC's technical director in 1964. He was president of the Royal Aeronautical Society in 1962/3. He remained one of the world's leading aerodynamicists.
If he wrote it I believe it to be so 
I have to take his word for I because I am not qualified to debate it.
Cheers
Steve


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## Balljoint (Jul 29, 2013)

Tante Ju said:


> How does elliptic planform reduce induced drag? I have not seen any glider with elliptic wings, all seems to have very high aspect ratio trapezoid wings. See also Ta 152.




Just a guess, but generally speaking, it does have reduced frontal area relative to total wing area. Still guessing, at altitude the frontal area may be more important than form drag with the larger total area relative to frontal area also generating more lift per unit frontal area, i.e. a relatively lesser AoA.


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## OldSkeptic (Jul 30, 2013)

Hop said:


> Spitfire fighter production was around 3,800 in 1942. Hurricanes weren't up to fighter combat over Europe, Typhoons were few in number and not properly sorted for combat. The Germans produced about 4,500 109s and 190s in 1942.



Most German production was for the eastern campaign



> There were a lot of tip and run raids, anti shipping strikes and recce flights. The RAF had to maintain fighters the length and breadth of the UK.


Still more than enough, 75 squadrons in all, 50 of them Spitfires.




> 385 Spitfires were flown to Malta between March and early October 1942.


About a month's production basically.




> That sounds like what the Luftwaffe tried in the BoB. Grass airfields do not make good bombing targets. Especially when there are very large numbers of them, mostly empty.


The idea is that this brings them up, you can't leave planes on the ground.
Park did it to the Germans very successfully later, attacking from Malta.
Hung bombs off Spits, if they stayed on the ground they lost their planes, if they came up they got shot down.



> The Spitfire VIII didn't really come along until 1943. The Spitfire IX would have required modifications to increase the range, and at that time _more_ Spitfires were much more important than _better_ Spitfires. Look at those production figures again.


True about dates, a true LR Spit (later) would be invaluable supporting the US bombing campaign and lets BC bomb at day. But a MR Spit Mk V is also invaluable in the late 41/42 period.



> The numbers just aren't there. The Luftwaffe had numerical superiority and were just off the British coast in 1940 and still lost. The RAF had numerical superiority but were hundreds of miles from Germany in 1942. They didn't have enough planes to make deep penetration raids work. In fact, they only had enough to contest airspace over France, not drive the Luftwaffe from the skies, even within the range they did have.



They were there, the RAF threw away over 1,000 fighters in the 41/42 'leaning towards the enemy' campaign by Leigh Mallory. They obviously thought they had enough fighters to use them up like that.

But because they didn't have the range to press the Luftwaffe right to their airfields they achieved basically nothing, with a loss rate somewhere in the 4:1 range.
The JG2, 26, etc simply pulled their bases back and only fought when it suited them.

The issue is not whether or not FC should do it, because they actually tried very hard. 
The issue is fight more effectively to inflict a proper war of attrition on the Luftwaffe and that, in this case, was simply a question of range.

In other words, what they tried to do was bound to fail unless they increased the range of the Spit.

Now using my fuel model and changing it to the Spit V, instead of the Spit VIII, I get a 300 mile combat range with a 30 gal rear tank and a 45 gal drop tank (you have the option of a 90 gal drop tank too which allows more loiter time in the target area).

More then enough to push the Luftwaffe fighters away (ie if they move their bases further away then they will be out of range of the coast and effectively 
useless). If you fit the VIII leading edge tanks to the V, then 400 miles is fine too.

Note that the USAAF fitted 36 gals into the leading edges in their prototype, as opposed to the 26 gals in VIIIs and used a smaller rear tank with 2x62.5 gal drop tanks (same as the Mustang). Apparently it handled quite well.

Note these are conservative figures with takeoff and a climb to 20,000ft and 15 mins combat time (at max power). I also assume that you use all the rear tank straight away, though, at least in MK VIIIs and MK IXs, handling returned to normal at about 20 gal left. Say 10 gals in a Mk V?

If you factor that in and don't run down the rear tank fully, saving the remainder for the return, you can get a bit more (or use it as a reserve of course).

Naturally if you change the mission profile you can get a bit different nums, either a bit better or a bit worse (though to get worse you have to be fairly pessimistic with your assumptions, but certain missions types might do that, eg running at max cruise speed at low altitude all the time). As always, good pre-planning and coordination would be essential.

Note that a fair few MK Vs were fitted with 29 gal rear tanks and used for ferrying them to NA and Malta and so on (along with a 170 gal slipper tank). 

All gals are UK ones.


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## Glider (Jul 30, 2013)

Tante Ju said:


> How does elliptic planform reduce induced drag? I have not seen any glider with elliptic wings, all seems to have very high aspect ratio trapezoid wings. See also Ta 152.



They obviously vary but the Discus Gliders had a wing reducing in three stages resulting in a near elliptical wing to reduce costs. They are excellent gliders with a very good performance with near viceless handling, making it an ideal 'first' high performance glider. 

I can confirm that they are a lot of fun to fly and despite being eclipsed in competitions can give a good account of themselves given a bt of luck re conditions.


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## Aozora (Jul 30, 2013)

OldSkeptic said:


> The issue is not whether or not FC should do it, because they actually tried very hard.
> The issue is fight more effectively to inflict a proper war of attrition on the Luftwaffe and that, in this case, was simply a question of range.
> 
> In other words, what they tried to do was bound to fail unless they increased the range of the Spit.
> ...


 
One problem which would have needed to be sorted on the Mk V with a 30 gal rear tank was stability; Supermarine adopted counter-weights ("bob weights") in the elevator circuit to help solve some problems encountered in 1942 when several Spitfires broke up in flight due to longitudinal instability: as it turned out the problem was caused by bad loading at a squadron level, moving the cg back too far. I would assume that to achieve adequate stability with a 30 gal rear fuselage tank and drop tank not only would it have been wise to introduce the bob weights but also the increased elevator balance area of most Mk IXs and some late Mk VCs. The PR Spitfies could get away with using rear fuselage tanks without too many mods because they were expected to fly straight and level most of the time and only use drastic manœuvres when evading attack. 



OldSkeptic said:


> More then enough to push the Luftwaffe fighters away (ie if they move their bases further away then they will be out of range of the coast and effectively
> useless). If you fit the VIII leading edge tanks to the V, then 400 miles is fine too.
> 
> Note that the USAAF fitted 36 gals into the leading edges in their prototype, as opposed to the 26 gals in VIIIs and used a smaller rear tank with 2x62.5 gal drop tanks (same as the Mustang). Apparently it handled quite well.



One effective way to counter Spitfires with fuselage tanks would have been to intercept as far forward as possible, forcing the Spitfire pilots to try manœuvring with the fuselage tanks (say) 2/3rds full. Presumably leading edge tanks could be fitted Mk VII VIIIs because of the extra length and weight of the Merlin 60/70 series which helped counter-balance the extra fuel just ahead of the cg. Leading edge tanks on the Mk Vs, as well as rear fuselage tanks would entail modifications to the Spitfire's rear end. Possibly the larger pointed rudder would have helped? 



OldSkeptic said:


> Note these are conservative figures with takeoff and a climb to 20,000ft and 15 mins combat time (at max power). I also assume that you use all the rear tank straight away, though, at least in MK VIIIs and MK IXs, handling returned to normal at about 20 gal left. Say 10 gals in a Mk V?
> 
> If you factor that in and don't run down the rear tank fully, saving the remainder for the return, you can get a bit more (or use it as a reserve of course).
> 
> ...



The Spitfire IX/XVI PNs advise the pilot to take off using the main tanks, then switch to the fuselage tank at 2,000 ft and drain it before switching back to the main tanks. When fitted with the drop tank the policy was to take off on main, switch to fuselage, drain to 30 gal then switch to the drop tank, drain the drop tank, then switch back to rear fuselage, drain it, then back to main tanks. Of curse the pilot had to be careful not to get vapour locks by allowing the tanks to drain completely before switching over. All to keep the cg within limits.


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## stona (Jul 30, 2013)

Incidentally Shenstone held a sailplane pilot's "C certificate" whatever that was and was heavily involved with sailplane/glider design and designers during his time in Germany.
Cheers
Steve


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## Hop (Jul 30, 2013)

> Most German production was for the eastern campaign



Do you have a source for that? Murray says German fighter losses on the eastern front were about 120 a month May - September 1942.



> The idea is that this brings them up, you can't leave planes on the ground.
> Park did it to the Germans very successfully later, attacking from Malta.
> Hung bombs off Spits, if they stayed on the ground they lost their planes, if they came up they got shot down.



They were "coming up". Up to 4,000 sorties a month, depending on RAF activity. That's a similar sortie rate to Luftflotte Reich in the first quarter of 1944, but with a much smaller force. So the problem most definitely wasn't the Luftwaffe staying on the ground.



> They were there, the RAF threw away over 1,000 fighters in the 41/42 'leaning towards the enemy' campaign by Leigh Mallory. They obviously thought they had enough fighters to use them up like that.



This is where I can't understand the logic. The RAF lost 1,000 fighters and you want to put more fuel in them and fly further in to enemy territory. That's just going to increase losses further.



> But because they didn't have the range to press the Luftwaffe right to their airfields they achieved basically nothing, with a loss rate somewhere in the 4:1 range.
> The JG2, 26, etc simply pulled their bases back and only fought when it suited them.



They had ample range to reach the German fighter bases in France. Here are JG 26 airfields as of June 1942, with their distance from the British coast:

St. Omer-Wizernes 48 miles
St. Omer-Arques 50 miles
Abbeville-Drucat 65 miles
Wevelgem - 80 miles

All of these were in easy range of FC.



> The issue is not whether or not FC should do it, because they actually tried very hard.
> The issue is fight more effectively to inflict a proper war of attrition on the Luftwaffe and that, in this case, was simply a question of range.



Range is useful if you can't get to the fight. It's useful if you want to bomb targets that are otherwise out of range. Neither applied to the RAF in 1942. They didn't have the numbers to escort deep penetration raids in to Germany, they found all the combat they could possibly want over France.



> Now using my fuel model and changing it to the Spit V, instead of the Spit VIII, I get a 300 mile combat range with a 30 gal rear tank and a 45 gal drop tank (you have the option of a 90 gal drop tank too which allows more loiter time in the target area).



Firstly, any modifications will of course reduce the numbers of Spitfires available, so the numbers problem gets even worse for the RAF. 

Secondly, adding a 30 gallon read tank to the Spitfire V probably wouldn't help much.

The Spitfire IX was just about stable enough with 30 gallons left behind the pilot. But that had a heavier, longer Merlin engine in the front to counteract the extra weight in the back.



> More then enough to push the Luftwaffe fighters away (ie if they move their bases further away then they will be out of range of the coast and effectively
> useless).



If the RAF couldn't force the Luftwaffe away from St Omer, what good would more range do? 



> If you fit the VIII leading edge tanks to the V, then 400 miles is fine too.



That requires structural modifications that would disrupt production. There were large numbers of modifications that could be added to the Spitfire to improve it, but the problem was for most of the war the Spitfire was the only allied fighter that could take on the German fighters on equal terms. 



> Note that the USAAF fitted 36 gals into the leading edges in their prototype, as opposed to the 26 gals in VIIIs and used a smaller rear tank with 2x62.5 gal drop tanks (same as the Mustang). Apparently it handled quite well.



According to Supermarine the US wing leading edge tanks compromised structural strength to an unacceptable degree. 

The Spitfire certainly could have its range increased, the various modifications in 1943 and 1944 proved that. But I don't think those modifications are practical in 1942, both for technical reasons and because the RAF were still desperate for more Spitfires (indeed even the USAAF and VVS wanted them as well)



> Note these are conservative figures with takeoff and a climb to 20,000ft and 15 mins combat time (at max power). I also assume that you use all the rear tank straight away, though, at least in MK VIIIs and MK IXs, handling returned to normal at about 20 gal left. Say 10 gals in a Mk V?
> 
> If you factor that in and don't run down the rear tank fully, saving the remainder for the return, you can get a bit more (or use it as a reserve of course).
> 
> Naturally if you change the mission profile you can get a bit different nums, either a bit better or a bit worse (though to get worse you have to be fairly pessimistic with your assumptions, but certain missions types might do that, eg running at max cruise speed at low altitude all the time). As always, good pre-planning and coordination would be essential.



I don't think the modification for a rear tank is worth it for an extra 10 gallons. A better solution would be fit the enlarged forward tank (total 95 gallons) and hang a 90 gallon drop tank underneath.

But that doesn't really solve many problems in 1942. The Luftwaffe in France is still a force capable of flying more than 4,000 sorties a month in defence (about the same as Luftflotte Reich in 1944). It's beyond the capabilies of the RAF to defeat it in 1942.


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## Edgar Brooks (Jul 30, 2013)

OldSkeptic said:


> Still more than enough, 75 squadrons in all, 50 of them Spitfires.


Thankfully, the government didn't feel that they should leave these shores undefended, after all dead civilians can't produce, and repair aircraft.


> About a month's production basically.


In 10 years 22,00 Spitfires and Seafires were produced, at an average of 42 per week.


> The idea is that this brings them up, you can't leave planes on the ground.


The Germans were only interested in Germany; occupied countries could be destroyed as far as they were concerned.


> Park did it to the Germans very successfully later, attacking from Malta.
> Hung bombs off Spits, if they stayed on the ground they lost their planes, if they came up they got shot down.


2 x 250lbs, which meant nothing except the odd pinprick


> Now using my fuel model and changing it to the Spit V, instead of the Spit VIII, I get a 300 mile combat range with a 30 gal rear tank and a 45 gal drop tank (you have the option of a 90 gal drop tank too which allows more loiter time in the target area).


It would appear that you don't listen to what you're told:- the Mk.V HAD to use the 90-gal ferry tank with a tank behind the pilot. The 45-gal was NOT AN OPTION, and, if the under-belly tank was dropped, there was no way to get the fuel out of the fuselage tank, which would make the aircraft increasingly unstable.


> If you fit the VIII leading edge tanks to the V, then 400 miles is fine too.


Can't be done, since the leading edge "D" boxes, on the V, contained the pipes used for heating the outboard pairs of .303" Brownings.


> Note that the USAAF fitted 36 gals into the leading edges in their prototype, as opposed to the 26 gals in VIIIs and used a smaller rear tank with 2x62.5 gal drop tanks (same as the Mustang). Apparently it handled quite well.


And when it arrived back here, Farnborough condemned it, since the leading edges had been weakened, so much, to get the tanks in, the airframe was deemed unfit for combat purposes.


> Note these are conservative figures with takeoff and a climb to 20,000ft and 15 mins combat time (at max power). I also assume that you use all the rear tank straight away, though, at least in MK VIIIs and MK IXs, handling returned to normal at about 20 gal left. Say 10 gals in a Mk V?
> If you factor that in and don't run down the rear tank fully, saving the remainder for the return, you can get a bit more (or use it as a reserve of course)


I repeat; if the drop tank has gone, the rear tank becomes a waste of space, and aerodynamic liability.
The VIII IX never had fuselage tanks fitted behind the pilot. The Air Ministry wanted them in every Spitfire, but were persuaded against it, so only the XVI had them, and then not until 1945.


> Note that a fair few MK Vs were fitted with 29 gal rear tanks and used for ferrying them to NA and Malta and so on (along with a 170 gal slipper tank).


Not while Malta was under siege, they didn't; all Spitfires were flown off carriers, with only a 45-gallon tank, and nothing behind the pilot. Any more and they'd never have got off the carrier decks.


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## swampyankee (Jul 30, 2013)

gumbyk said:


> Why wouldn't you use them?
> 
> There is a reason laminar flow aerofoils are in popular use. They work.



For the laminar flow airfoils available during the WW2-era, normal practice was to assume that the "drag bucket" did not exist, as the required surface finish could not be maintained in service. Even without this, the NACA 6 series airfoils, like the 65A215, have many positive properties. Incidentally, if you want to maintain laminar flow wings in service, completely give up the idea of wing-mounted guns. 

Long-range Spitfire:
1) Root plugs, to increase span. Use the added wing volume for fuel tankage.

2) Extend the fuselage about 24 inches for the same reason. Probably the best way to do this would be to add some frames near the c/g.

3) Engine cooling system drag is a major concern on all aircraft. The Mustang probably had the best cooling system design of any aircraft, but the same effect can be achieved with other configurations, that is the belly duct and radiator is not the only solution. 

4) All aircraft, especially combat aircraft, have lots of less-than-optimal bits of ducting, venting, doors, seals, etc. These could be cleaned up, but doing so may make servicing more difficult


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## Juha (Jul 30, 2013)

Edgar Brooks said:


> ...It would appear that you don't listen to what you're told:- the Mk.V HAD to use the 90-gal ferry tank with a tank behind the pilot. The 45-gal was NOT AN OPTION, and, if the under-belly tank was dropped, there was no way to get the fuel out of the fuselage tank, which would make the aircraft increasingly unstable.



Really, when looking the diagrams in Spitfire The History p. 149, it seems odd that with the droptank fuelcock shut and the rear tank fuelcock open there was a need to the droptank being in place. And even more difficult to understand why it had to be 90gal DT, what is wrong with 45gal? And Spit Vs with 29gal rear tank and with 170gal DT flew directly from Gibraltal to Malta in late 42, see for ex Price's The Spitfire Story or Shores' et al Malta: The Spitfire Year.

Juha


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## Aozora (Jul 30, 2013)

Edgar Brooks said:


> This love of the bob-weight is interesting, since experienced pilots didn't like it, due to loss of manoeuvrability, and Mike Crosley was of the opinion that it killed more pilots than it saved, since, when a pilot inverted the aircraft to abandon it, the weight worked in the opposite sense, and slammed the elevators hard up, giving the pilot no chance to get out.



As Quill explained carefully in his book the bob-weights were an emergency measure introduced to counter Spitfire Vs breaking up in flight in alarming numbers in 1942, due to poor loading at a unit level. Like most such emergency measures they were a compromise which at least helped curtail a far bigger problem at the expense of some changes in how the elevator felt to the pilot. Once the elevators were redesigned with larger balances the bob-weights could be dropped. 

As for the claims about the weights killing more pilots than were saved, does Mike Crosley have any evidence, such as solid figures, to back up his claims?

One big problem with fitting Spitfire Vs with rear fuselage tanks and operating them over Europe: the Fw 190. How could Spitfire Vs with full or half full tanks cope with being attacked by 190s, or even 109F-4s, when the standard variants were so badly outclassed? Doesn't bear thinking about really...


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## Edgar Brooks (Jul 31, 2013)

Juha said:


> Really, when looking the diagrams in Spitfire The History p. 149, it seems odd that with the droptank fuelcock shut and the rear tank fuelcock open there was a need to the droptank being in place. And even more difficult to understand why it had to be 90gal DT, what is wrong with 45gal?


I'm afraid that you'd need to address that question to those who wrote the manuals during the war, since they don't go into that sort of detail; going by the drawings, I'd guess (and can only guess) that, in the 90-gal tank, there was enough fuel forward of the CoG to counterbalance the fuel in the rear tank, but not in the 45-gal. Losing the droptank, and having fuel sloshing about behind the pilot, would, in my view, make control extremely difficult, if not impossible. How often did P-51 pilots use, and drop, their extra tanks, before emptying the fuselage tank?


> And Spit Vs with 29gal rear tank and with 170gal DT flew directly from Gibraltal to Malta in late 42, see for ex Price's The Spitfire Story or Shores' et al Malta: The Spitfire Year.


 But did any of them use the 29-gal tank with a 45-gal droptank? Somehow I doubt that you'll find any examples, and don't forget that the siege was over, so likelihood of attack, from the African coast was gone.
The only airframe(s) to have the tank were the XVI and (possibly) the F.R.XIV; post-war, pilots were banned from using the rear tank, in fact, there was a ruling that the filler cap should be wired shut.
Today's Tornado's fin is a fuel tank; the fuel, in it, has to be used first, and, if it refuses to feed, pilots have to abort their mission, immediately.


> As for the claims about the weights killing more pilots than were saved, does Mike Crosley have any evidence, such as solid figures, to back up his claims?


Only his work, as a test pilot, with Boscombe Down, post-war; dead pilots don't return, to give reports, and, as he is now also deceased, it's not possible to ask him anything.


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## OldSkeptic (Jul 31, 2013)

Edgar Brooks said:


> I repeat; if the drop tank has gone, the rear tank becomes a waste of space, and aerodynamic liability.
> The VIII IX never had fuselage tanks fitted behind the pilot. The Air Ministry wanted them in every Spitfire, but were persuaded against it, so only the XVI had them, and then not until 1945.



Spit IX and IVI (they were identical planes except for the engine) long range fuel system:
Seems smple to me, turn on/off drop tank fuel, turn on/off rear tank fuel.







And here is the conclusions of testing a LF MK IX with a 75 gal rear tanks. Conclusions was that it was cleared for combat with 41 gals left....


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## OldSkeptic (Jul 31, 2013)

Edgar Brooks said:


> It would appear that you don't listen to what you're told:- the Mk.V HAD to use the 90-gal ferry tank with a tank behind the pilot. The 45-gal was NOT AN OPTION, and, if the under-belly tank was dropped, there was no way to get the fuel out of the fuselage tank, which would make the aircraft increasingly unstable.



Even if this true (and I can't find any reference it and it doesn't make intuitive sense since, from a simple safety point of view you would want to be able to isolate different tanks), somehow I don't thing it was beyond British engineering to ...change the fuel switches so you can go from one tank to the other.....

PR versions, based on the k I and Mk V had all sorts of (and combinations of) fuel tanks, anything from 20-30 gals under the pilot's seat, 20-30 gals behind the pilot, plus a whole range of drop tanks depending on the mission requirements.
Somehow they managed to plumb it up so that tanks could be switched....... amazing eh?

The MK V was the most sensitive of all of the Spits to CoG issues ... until they put the bob weight (more accurately, an inertial balance) on and later the revised elevator.
Note bob weights were retained on the pressurised Spits (VII etc), because the friction of the seals on the control lines caused elevator instability.


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## Juha (Jul 31, 2013)

Edgar Brooks said:


> I'm afraid that you'd need to address that question to those who wrote the manuals during the war, since they don't go into that sort of detail; going by the drawings, I'd guess (and can only guess) that, in the 90-gal tank, there was enough fuel forward of the CoG to counterbalance the fuel in the rear tank, but not in the 45-gal. Losing the droptank, and having fuel sloshing about behind the pilot, would, in my view, make control extremely difficult, if not impossible. How often did P-51 pilots use, and drop, their extra tanks, before emptying the fuselage tank?



That is a possibility. But as in P-51, after t/o first use the fuel in the rear tank until it was enough emptied for safe manoeuvring then switch to the DT(s). In early PR Spits with the rear tank, the idea was to use first the fuel from the 29gal rear tank, then to switch to the main tanks.



Edgar Brooks said:


> But did any of them use the 29-gal tank with a 45-gal droptank? Somehow I doubt that you'll find any examples, and don't forget that the siege was over, so likelihood of attack, from the African coast was gone.



45gal or 90gal DT were too small for a flight from Gibraltar, so 170gal was the only option. And the siege wasn't over, in fact the danger from LW fighters was highest at that time, Germans had moved to Tunisia with force in early Nov 42 and there was much trafic between Sicily and Tunisia incl. fighters, moving to Tunisia and escorting shipping and transport planes. The Axis didn't surrender until early May 43.

Juha


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## OldSkeptic (Jul 31, 2013)

Aozora said:


> As Quill explained carefully in his book the bob-weights were an emergency measure introduced to counter Spitfire Vs breaking up in flight in alarming numbers in 1942, due to poor loading at a unit level. Like most such emergency measures they were a compromise which at least helped curtail a far bigger problem at the expense of some changes in how the elevator felt to the pilot. Once the elevators were redesigned with larger balances the bob-weights could be dropped.
> 
> As for the claims about the weights killing more pilots than were saved, does Mike Crosley have any evidence, such as solid figures, to back up his claims?
> 
> One big problem with fitting Spitfire Vs with rear fuselage tanks and operating them over Europe: the Fw 190. How could Spitfire Vs with full or half full tanks cope with being attacked by 190s, or even 109F-4s, when the standard variants were so badly outclassed? Doesn't bear thinking about really...



The accident investigation people of the day concluded that the loss of Spits due to wings coming off dropped away after the bob weights (etc) were introduced.

As for the 190, it depend on the time we are talking about.

In mid 41 onwards, when FC first started its 'leaning towards the enemy' approach (and Portal with in incessant opposition to long range fighter became CAS) there were no 190s in any significant numbers (plus they were very buggy at that time). The issue to deal with them was good tactics (naturally once numbers came up they needed the MK IX).

The tactical problem they faced, having very limited range (and no will to change that), was bringing the Luftwaffe to combat in favourable terms. That they couldn't do.

They never attacked the Germans radar (until just before D-Day in fact and that was only thanks to RV Jones*), therefore they could not achieve tactical surprise, they wouldn't or couldn't attack anything the Germans cared about. If they did fighter sweeps the Germans ignored them (as Park did to them in the BoB). If they sent bombers in they could only go to very close targets.

In fact JG2 26 simply could have done nothing at all if they wanted. But fighter pilots being fighter pilots they did engage .. but only where and when they could get their top pilots lots of gongs for easy kills.

The 190s were a shock, even though they were altitude limited, but because, to bring them up, they sent in escorted bombers they were at relatively low altitudes where the 190 shone.
Their own escort tactics were poor, placing, initially undue numbers of plane in close support. Took far too long to work out the correct pattern of close (but not too close) high along with a forward sweep.
It was if everything they had seen done wrong by the Luftwaffe in the BoB they were determined to copy, with similar results.

Park showed the way when he went on the offensive from Malta into Sicily (etc). Increased range with drop tanks, mixed pure fighters with Spits carrying bombs (and they dropped the racks with the bombs, thus turning them back into pure fighters again, the racks could cost anything up top 20mph in speed).

Then he used the Spits as very successful dive bombers, which though they only had a small bomb load (2x250lb)) they were (with training) very accurate.
So if the Luftwaffe stayed on the ground they would lose planes, therefore their fighters would have to come up and at a tactical disadvantage.
The proof is in the pudding, so to speak, the Luftwaffe basically abandoned Sicily before the landings.

Note that the Spit made a very good dive bomber capable of high angle, high G attacks. Its low wing loading, high G rating plus that good elevator authority at speed and light weight meant that it could attacks at very steep angles and still pull out. Other heavier fighter bombers (eg the Typhoon and P-47) had to attack at shallower angles and pull out earlier because they 'mushed' so much.
A small bomb aimed accurately is far more effective than a larger one that is inaccurate.

Now to do a successful campaign in 41 and 42 there were only 2 targets that were guaranteed to get the Luftwaffe fighters up, whatever their tactical position:
(1) Sending in bombers to attack the U-Boat pens being built in the Bay of Biscay coast.
(2) Attacking their airfields. Note that could have been (say) some of their bomber airfields.

Both cases depended on:
(1) Taking out their radar sites.
(2) Longer ranged Spits.

Target (1) was completely ignored (despite RN and Coastal Command pleadings) by Portal and dependency (2) was completely ignored (more accurately fought against for years, Oct 43 and still fighting against it) by Portal.
And since he was the boss, well that's why we got that whole sorry fiasco in 41 and 42.
And lots of JG2 26 boys got lots of gongs for shooting down strategically and tactically disadvantaged FC pilots (plus a fair few BC ones too).

That old saying "Lions led by donkeys' comes to mind....

* I lobe this story, Jones had been building up maps of every German radar station throughout Europe. BC was not interested in the least, in a famous comment, after Jones had laid out to Harris the complete German radar defence network he commented "well that shows we're hurting them", as Jones commented his thoughts were "more likely that will hurt you".

Anyway he had been tracking and documenting and arranging all sorts of things (resistance spying, photo recon, signals,et al) to build a compete map of the German coastal radar network.

In March 44 he went to Tedder (since no one had contacted him about it and there were precisely zero anti-radar plans by the allies) about it through unofficial channels and finally someone from SHAFE turned up. The rest as they say was history.


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## Glider (Jul 31, 2013)

In Italy the use of 90 gallon drop tanks on operations with Spits was almost the norm. The problem they had, was that there were not enough tanks to go around.

The following docs support this view


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## Glider (Jul 31, 2013)

This also may be of interest. It shows how the rear tank was standard in the later Spit IX


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## vinnye (Jul 31, 2013)

From Wiki ;
The Mk Vb was the first Spitfire to see extensive overseas service. On 7 March 1942, 15 Mk Vs carrying 90-gallon fuel tanks under their fuselages took off from HMS Eagle off the coast of Algeria on a 600-mile flight to Malta.[158]

In the months that followed, some 275 Mk Vb and Vc Spitfires were delivered to the beleaguered island, with the Americans generously providing help by allowing the USS Wasp to be used to fly two lots of Spitfires to the islands. Wooden wedges were used to allow the Spitfires to leave the carrier with partial "takeoff" flap settings. (Once the aircraft had gained altitude, the pilot would open the flaps fully, the wedges would fall out and the flaps could then be closed.) In "Operation Calendar" on 20 April 1942, 47 Spitfires and pilots of 601 and 603 Squadrons flew from Wasp to Malta.[159] In "Operation Bowery" on 9 May 1942, another 50 Spitfires flew from Wasp and 14 from Eagle. Sixty of them landed on Malta. One Spitfire with a defective long range fuel tank landed back on the Wasp, despite lacking a tailhook.[160] In "Operation Style" on 3 June, a further 32 Spitfires flew to Malta from HMS Eagle, through they were intercepted en route and four were shot down.[161] However, the carriers were thought to be vulnerable to attack from the Luftwaffe while out at sea[162] so in late October through to early November, a total of 12 Spitfire Vcs, equipped with a single huge 170-gallon drop tank, flew direct from Gibraltar, a distance of 1,000 miles.[145] This meant a flight time of more than five hours.

I did not know that they used such large tanks to fly direct.


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## Edgar Brooks (Jul 31, 2013)

It really is quite incredible; we start with an incorrect belief, regarding the Mk.V, and, when I correct that, everyone piles in with material about the Mk.IX, even going as far as including a page from a post-war manual, and 1945 test reports on a specially converted airframe.
I did not think I would need to remind you all that the IX is/was a different airframe from that of the V, with different capabilities, and different CofG settings. Also, the aircraft that did the non-stop flight between Gibraltar and Malta, carried no cannon, had reduced ammunition on the remaining .303" Brownings, and preferably needed still-air conditions to give them a chance. They, most certainly, did not carry any fuel behind the pilots.
As far as Malta is concerned, the siege ended at the end of December 1942.


> The accident investigation people of the day concluded that the loss of Spits due to wings coming off dropped away after the bob weights (etc) were introduced.


Can you tell me where (and when) this report is, please, because I've never seen it, or any mention of it.


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## Glider (Jul 31, 2013)

I think you will find that the Mk V was a very similar airframe to the Mk IX. The weights were different of course but in essence they were very similar, some of the early Mk IX's being converted mk V's.
No one is denying that the Mk V didn't have the rear tanks as by that time the Mk V wasn't the formost version but there was no reason why they couldn't have done these changes to a Mk V


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## Juha (Jul 31, 2013)

Hello Edgar
as I wrote in my previous message, both Shores and Price say that those Spit Vs which flew from Gibraltar to Malta had the rear fuselage 29gal tank. Only 2 mgs in place. the first flight was late Oct 42, on 25th, and the Axis had fighters in Tunisia until early May 43.

Juha


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## Shortround6 (Jul 31, 2013)

Glider said:


> I think you will find that the Mk V was a very similar airframe to the Mk IX. The weights were different of course but in essence they were very similar, some of the early Mk IX's being converted mk V's.
> No one is denying that the Mk V didn't have the rear tanks as by that time the Mk V wasn't the formost version but there was no reason why they couldn't have done these changes to a Mk V



While the airframes were very similar that does NOT mean you can add the same accessories/fuel tanks. the Merlin 60 series engines weighed roughly 250-270lbs more than the Merlin 45-55 engines. They also used 4 Blade propellers instead of 3 blade did they not? A lot more weight forward of the CG, Granted teh MK IX had the bigger radiators behind but it is all about moment arms. How many pounds at how many inches from the CG. A lot of Spitfires carried ballast to keep the CG located properly but without ballast a MK V is a lot lighter in the nose than a MK IX so adding weight in the tail is going to be harder to balance. Some (all without tanks?) MK IXs carried 87.5 of ballast in the tail, I don't know if the planes with the fuel tanks carried the same or less ballast but even at a distance 1/3 of the way to the tail location that is only 262.5lbs. That is about 36 Imp gallons of fuel NOT counting the weight of the tank/s. 
If MK IXs were considered dangerous to fly with rear tanks what is a MK V going to be with around 300lbs less weight in the nose?


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## Edgar Brooks (Aug 1, 2013)

Shortround has it exactly; to counteract the extra weight/moment arm of the longer, heavier 60-series Merlin + 4-blade prop, the oxygen bottle (sometimes two) was moved to the rear hatch, and lead weights were installed near the tail wheel (on the XIV, with the even heavier Griffon, they went into the fin.) This meant that the IX, with weights removed, had a fighting chance to have the tank installed, while the V couldn't, without the bigger ferry tank, since it had no means to compensate.
When the XVI was envisaged, with fuel tank, again for reasons of balance the oxygen and compressed-air bottles had to be removed, and fitted into the wings, in the compartments usually filled by the four .303" Brownings. This meant that the XVI had to have the E wing, and the Air Ministry wouldn't countenance that until the gyro gunsight was available. With all of the extra weight, the XVI had to have stronger wheels, and metal-covered elevators just to get off the ground.
The Air Ministry wanted all Spitfires to have rear fuel tanks, but the C.O. of 11 Group (successfully) fought against it, because the tanks adversely affected manoeuvrability, rate of climb, and operational ceiling.


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## OldSkeptic (Aug 1, 2013)

Shortround, oh the Mk V would be more CoG sensitive, even with the elevator fixes, hence my proposing a smaller rear tank (and perhaps an under the seat tank as per some PR versions).

Probably would be the same with 30 gals as a Mk IX with 66 or 75 gals. And you would have to run it down to, perhaps, only 10 gals to return to normal.
Remember 10 gals is only about 100lbs.

You could even do the L shaped stank (ah lah the 109), so when you run it down most is under the pilot.

Might need a bob weight but seems doable.

They shoved more into the PR versions than that, plus they had the camera weight to the rear as well.


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## Glider (Aug 1, 2013)

The very first Spits were tail heavy and had weights in the nose, how much I do not know. There is no reason why the same could not be done again.
I am not trying to pretend that the same tanks as the IX but to pretend that nothing could be done I do not agree with.

Re the decision of 11group not to use the rear tank I can understand as they were interceptors but what about everyone else. The Italian campaign were almost desperate for extra range as well as the 2TAF. 

Do you know when 11group won their argument?


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## Edgar Brooks (Aug 1, 2013)

Glider said:


> The very first Spits were tail heavy and had weights in the nose, how much I do not know. There is no reason why the same could not be done again.


Early Mk.Is had weights to compensate for the lightness of the two-blade propellers; they were discontinued as soon as the three-blades appeared. Weights caused stress on the engine bearers, so were discarded as soon as possible. The bearers still had to be strengthened, on the V, with the introduction of the more powerful 50-series Merlins.


> I am not trying to pretend that the same tanks as the IX but to pretend that nothing could be done I do not agree with.


Excuse me, but where does this "pretend" come from? If the Air Ministry wanted something to be tried, they asked the manufacturers to produce an example (or, if necessary several,) which then went to Farnborough, Boscombe Down, the F.I.U., or any other test centre, to be tested by experienced pilots, who reported back on their findings. If the Air Ministry wanted it to go ahead, they told the factory's Resident Technical Officer, whose job it was to see that it was implemented. Going in the other direction, if the company wanted to institute a change, it had to be presented to the Local Technical Committee, who vetted it, then gave the go-ahead (or not.) there were 1,900 modifications on the Spitfire, and 1090 on the Seafire, not all of which eventually went ahead.


> Re the decision of 11group not to use the rear tank I can understand as they were interceptors but what about everyone else. The Italian campaign were almost desperate for extra range as well as the 2TAF.


Italy got the VIII, which had extra wing tanks; do you know, for sure, that the Med H.Q. were wanting fuselage tanks? I've never seen any requests for them, in any files that I've read.


> Do you know when 11group won their argument?


As far as I know they never lost it, rather than winning, since they never had the tanks fitted in anything but the XVI, and (possibly) the F.R.XIV with cut-down fuselages.


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## OldSkeptic (Aug 1, 2013)

Everyone seems to be forgetting the "Portal' effect. He was the CAS. His position, which he very actively held until Oct 43 was that a long range fighter was impossible.
He is on record writing to the Americans and Churchill saying that, over and over again.
Two months before the P51B came onto operations he was still arguing with Arnold about it. There was not a single chance he was going to convert Spits to LR operations, he had hung his prestige on that one.

Now, take any organisation, going against the boss's wishes is not a good way to get promoted.
Imagine if someone had successfully fielded a LR Spit on operations, they would have made him look like a fool.
Imagine how he was going to react if, after telling the Prime Minister, in print (many times) that it was 'impossible', then someone comes along and does it .. are you going to be the one who tells him that? 
Welcome to the RAF's Siberian Command...or 'here is a nice Antarctic base you can be in charge of'.

There was no way Leigh Mallory (11 Grp head 40 to 42) or Saunders (42+) were going to take those sort of career hits, being competent but not politically savvy didn't get you far in the RAF. 
Note how the most innovative areas of it were in theatres well away from Britain and out of Portal's woeful gaze (and he was not happy about it and made that clear, but the DAF had become so successful even he couldn't kill it). As for Malta, Italy, etc? Oh yes Park was pushing for it, look what happened to him, at the end of the war he was told 'there was no position for him'. Tedder did ok, but he had Monty and Eisenhower behind him, that helped, otherwise I think his career would have taken a very left run along the way. 

So you got 'self censoring'. If you were a politician like LM, you knew that Portal had hung his hat on the LR 'impossibility', what are you going to do? Prove him wrong, not likely.

As for Boscom Down et al, while they were twittering away if a Spit had 0.5" CoG too far, the USAAF just got on with it, slapped rear tanks into their Mustangs and flew the blasted things into missions.
Note that a Mustang was just as unstable with its rear tank full as a Spit was.
Note that BD were the ones that had earlier said putting cameras in the rear of a Spit was 'impossible ' too. Until Cotton just did it.

This attitude became institutional, to the point where British Mustangs had their rear tanks removed....
Even after the war, think of a British made LR fighter ... yeh short list isn't it.

Even Quill remarks on that. In his book he tells of doing a LR test with a Mk IX, rear tank, 90 gal drop tank, flew to the North of Scotland and back (at low altitude too), same distance as round trip to Berlin.
He commented that at BD they tended to underestimate the average pilot and that if the plane wasn't just absolutely perfect they just wouldn't clear it.
Look at how they frigged around with the Spit 21 and the Spiteful, reading their test reports is almost embarrassing. If it didn't behave just like an earlier Spit in every regime they were not going to clear it.

You can't help but wonder if they would have ever have cleared the Merlin Mustang if it has been a purely British plane, given its stability issues in the beginning. And they would never have cleared it with the rear tank.


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## Glider (Aug 2, 2013)

Edgar Brooks said:


> Early Mk.Is had weights to compensate for the lightness of the two-blade propellers; they were discontinued as soon as the three-blades appeared. Weights caused stress on the engine bearers, so were discarded as soon as possible. The bearers still had to be strengthened, on the V, with the introduction of the more powerful 50-series Merlins.


So we agree that the engine bearer coud be strengthened to take the extra weight.


> Excuse me, but where does this "pretend" come from? If the Air Ministry wanted something to be tried, they asked the manufacturers to produce an example (or, if necessary several,) which then went to Farnborough, Boscombe Down, the F.I.U., or any other test centre, to be tested by experienced pilots, who reported back on their findings. If the Air Ministry wanted it to go ahead, they told the factory's Resident Technical Officer, whose job it was to see that it was implemented. Going in the other direction, if the company wanted to institute a change, it had to be presented to the Local Technical Committee, who vetted it, then gave the go-ahead (or not.) there were 1,900 modifications on the Spitfire, and 1090 on the Seafire, not all of which eventually went ahead.


And we agree that there was a process to test the idea if someone had come up with it


> Italy got the VIII, which had extra wing tanks; do you know, for sure, that the Med H.Q. were wanting fuselage tanks? I've never seen any requests for them, in any files that I've read.


True but the papers I put forward show that they were very keen on the extra range which is why they used the 90 tanks on opps.


> As far as I know they never lost it, rather than winning, since they never had the tanks fitted in anything but the XVI, and (possibly) the F.R.XIV with cut-down fuselages.


And now we are agreeing that they had the rear tanks on the XVI which is almost exactly the same as the IX.

Add the papers I presented that showed the rear tanks were in production for retro fitting to the Mk IX and future installation in new production IX and we have the case for the Mk IX with rear tanks.

I also have other papers which show the Air Ministry when asking about the long range performance of fighters generally included the Spit IX with the rear tanks.


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## Edgar Brooks (Aug 2, 2013)

OldSkeptic said:


> Note that BD were the ones that had earlier said putting cameras in the rear of a Spit was 'impossible ' too. Until Cotton just did it.


Except he didn't; he put them in the wings, after removing the guns and ammunition.


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## Edgar Brooks (Aug 2, 2013)

Glider said:


> So we agree that the engine bearer coud be strengthened to take the extra weight.


Torque, not weight.


> And we agree that there was a process to test the idea if someone had come up with it


And reject it if no advantage could be found.


> True but the papers I put forward show that they were very keen on the extra range which is why they used the 90 tanks on opps.


Which could be dropped, when necessary, leaving the airframe still capable of combat manoeuvres.


> And now we are agreeing that they had the rear tanks on the XVI which is almost exactly the same as the IX.


Except it was configured for ground attack, while the standard IX was earmarked for fighter operations.


> Add the papers I presented that showed the rear tanks were in production for retro fitting to the Mk IX and future installation in new production IX and we have the case for the Mk IX with rear tanks.


Good enough for you, 70 years later, but not good enough for those with the responsibility for sending pilots to their deaths.


> I also have other papers which show the Air Ministry when asking about the long range performance of fighters generally included the Spit IX with the rear tanks.


The chair-bound Air Ministry mandarins wanted them; those who did the fighting didn't want them.


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## OldSkeptic (Aug 2, 2013)

Edgar Brooks said:


> Except he didn't; he put them in the wings, after removing the guns and ammunition.





> n the Mk I PR Type B (also known as Medium Range (MR)) conversions which followed, the F24 camera lenses were upgraded to an eight inch (203 mm) focal length, giving images up to a third larger in scale. An extra 29 gal (132 l) fuel tank was installed in the rear fuselage. It had been envisaged that much larger cameras would be installed in the fuselage immediately behind the pilot, but at the time RAF engineers believed this would upset the Spitfire's centre of gravity. *Cotton was able to demonstrate that by removing lead weights, which had been installed in the extreme rear fuselage to balance the weight of the constant speed propeller units, it was possible to install cameras with longer focal-length lens in the fuselage. *The Type B was the first to dispense with the heavy bullet resistant windscreen. Many of these early PR Spitfires were fitted with the Merlin XII engine and Rotol constant-speed propeller with the early, blunt spinner of the Spitfire Mk II.[58]


Supermarine Spitfire (early Merlin-powered variants) - Wikipedia, the free encyclopedia



> The Mk I PR Type D (also called the Extra Super Long Range Spitfire) was the first PR variant that was not a conversion of existing fighter airframes. The Type D carried so much fuel that it was nicknamed "the bowser." The D shaped wing leading edges, ahead of the main spar, proved to be an ideal location for an integral tank. Accordingly, in early 1940, work started on converting the leading edges, between rib four through to rib 21, by sealing off the spar, outer ribs and all skin joins allowing 57 gal (259 l) of fuel to be carried in each wing. Because the work was of low priority, and with the urgent need for fighters the first two, hand-built prototypes of the PR Type Ds were not available until October. In addition to the leading edge tanks these prototypes also had a 29 gal (132 l) tank in the rear fuselage. An additional 14 gal (63 l) oil tank was fitted in the port wing. The cameras, two vertically mounted F24s with 8 inch (20.3 cm) or 20 inch (50.8 cm) lens or *two vertically mounted F8s with 20-inch (510 mm) lens, were located in the rear fuselage*. With the full fuel load the center of gravity was so far back the aircraft was difficult to fly until the rear fuselage tank had been emptied. Despite these difficulties the type quickly proved its worth, photographing such long distance targets as Stettin, Marseilles, Trondheim and Toulon.[60]
> 
> Once the first two Type Ds, P9551 and P9552[61] had proven the concept the production aircraft, which were soon redesignated PR Mk IV, were modified to increase the leading edge tank capacity to 66.5 gal (302 l) and by omitting the rear fuselage tank. These aircraft were better balanced and had the more powerful Merlin 45 engine as used by the Mk V, along with heated cabins, which were a great comfort to pilots on such long flights. A total of 229 Type Ds were built.[62]



And here is something interesting:


> Mk I PR Type F was an interim "super-long-range" version which entered service in July 1940, pending the Type D. The Type F carried a 30 gal fuel tank under each wing, plus a 29 gal tank in the rear fuselage, as well as having an enlarged oil tank under the nose. It was a useful enough improvement that nearly all existing Type Bs and Type Cs were eventually converted to the Type F standard. Operating from East Anglia it was just able to reach, photograph and return from Berlin. 15 of these were based on the Mk V airframe.[10]
> 
> *The Mk I PR Type G was the first fighter-reconnaissance version *and performed a similar low-level tactical role to the Type E. *One oblique F24 camera, with either an eight inch or 14 inch lens, was fitted facing to port, between fuselage frames 13 and 14. Two vertical F24 cameras were also installed in the fuselage.* The forward camera, installed below the oblique, could be fitted with a five inch or an eight inch lens while the rear camera could be fitted with an eight inch or a 14 inch lens.[64] A* 29 gal (132 l) fuel tank was fitted just behind the pilot*. The first PR Gs were converted from Mk I airframes and their Merlin II engines replaced with Merlin 45s.[64] Late PR Gs were converted from Mk V airframes. T*he Type G was fully armed with 8 × .303" Brownings and retained the armoured windscreen and gunsight*.[64]


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## Tante Ju (Aug 2, 2013)

Glider said:


> Add the papers I presented that showed the rear tanks were in production for retro fitting to the Mk IX and future installation in new production IX and we have the case for the Mk IX with rear tanks.



Are there any papers showing how many production Mark Niners were retrofitted with those rear tanks?


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## stona (Aug 2, 2013)

It's something of an understatement to say that the PR ID was difficult to fly. According to one who flew it:

"You could not fly straight and level for the first half our or hour after take off. Until you had emptied the rear tank, the aircraft hunted the whole time. The centre of gravity was so far back you couldn't control it."

I'd suggest that whilst just about acceptable for a solo reconnaissance aircraft in war time this would be unacceptable for a fighter in squadron service. Formation flying would certainly be challenging!

Cheers

Steve


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## Juha (Aug 2, 2013)

One must remember that PR ID carried 2 cameras in rear fuselage, especially those with 20" lenses were not so light. Of course the 114gal fuel in the leading edges torsion boxes compesated that at least partially. I cannot say was the ID's GC more aft than that of Vc with a full rear fuselage tank and a dt. IMHO only if the GCs were near each other we can draw conclusions from the behavior of ID.

Juha


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## OldSkeptic (Aug 3, 2013)

stona said:


> It's something of an understatement to say that the PR ID was difficult to fly. According to one who flew it:
> 
> "You could not fly straight and level for the first half our or hour after take off. Until you had emptied the rear tank, the aircraft hunted the whole time. The centre of gravity was so far back you couldn't control it."
> 
> ...



Mustangs fully fueled up were just as bad (and they also had the issue of lateral instability too in the earlier B/C versions) , the key thing is that they used up that fuel, returning the plane to normal before they got into a potential combat zone.

Usual was, take off an climb on rear tank, initial cruse to rendezvous on rear tank (or at least most of it until the CoG became reasonable), then drop tanks for the rest of cruise and escort phase. Drop them for combat and use normal internal fuel for that and return.

As usual careful planning, training and tactics were the key to success.

They used layered escorts, In 43 and early 44 it was Spits so far, then P-47s then Mustangs so the Luftwaffe couldn't do the obvious trick of doing feint attacks to make the planes lose their drop tanks.
If you had enough of one type then you would use a single type of plane with different fuel loads for the different stages. 

As for the Spit, you would use a similar pattern. As for formation flying, who cares by the time they did that sort of stuff tight formations were not used (simply big clumsy targets as they learned through bitter experience).

Good training would be essential of course, though the USAAF threw pilots into Mustangs and sent them off on long range escort missions because the need was so great. I read the account of one pilot, originally on P-47s, then Mustangs arrived, they got a quick go through of the setup and (if they were lucky) a quick test flight, then sent on an escort mission the next day basically.

No reason not to do it with Spits, as said even a Mk V with a 29 gal rear tank and a drop tank could do a 300 mile combat radius missions. That FR version of the MK I showed that, 'fighter recon' planes were expected to fight (though the best low level FR plane by far was the Mustang I, the P-51A).

The reasons the RAF didn't do were simply : Portal, Portal and Portal. He had hung his hat (and reputation) on that it was 'impossible', therefore there was no way it was going to happen, whatever the technical issues were. Heck, I'm quite sure he would have killed the Mustang if he could have.

The funny thing was that the RAF sent off bombers all the time were were hideous to fly when fully fueled up at the beginning of a mission. So it was ok for a bomber crew (including Mosquitos) to start their mission in an unstable, in some cases virtually unflyable and very definitely in a very dangerous state for take off and initial cruise to target.

But not for fighters, the pilots were obviously inferior of course.

You have to see Portal as the heir of the Trenchard dogma ... bombers, bombers and bombers .. and they will always get though .. and win by destroying the enemy's 'moral'.
And everything else was irrelevant. Harris famously wrote that Coastal Command, CC for short, (essential for winning the BoA) was 'an obstacle to victory' and urged that it should be shut down.
Portal half agreed (by his own memos), but was forced (though he fought hard against it) to give resources to CC. One of his famous memos was that CC should not get LR Liberators (totally essential for closing the Atlantic Gap) because ' the Americans might be annoyed that we are not using them for bombing Germany'. Where he was going to get the fuel for his bombers if Britain lost the BoA he never said.

RV Jones (read Most Secret War) tells the story of how he was trying to get the frequency of German night fighter radars, found that no one in BC was interested. Went to a senior BC person to try a get a Mosquito to do it (for obvious reasons as this was an extremely dangerous mission) and spent the time with this senior BC person talking about 'model trains', which was all that person cared about (naturally not his crews being slaughtered).

Never got that Mosquito, but finally got a Wellington crew to do it (????), they succeeded .. and got shot to pieces doing it (amazingly most survived). 

And that was the RAF in WW2 ... model trains are so important. Really competent people like Dowding and Park were gotten rid of, Cunningham and Tedder did well .. because they were far away from Portal's woeful gaze and because of their successes the senior British and American people (Monty, Eisenhower, etc) protected them.
Portal was not happy about it as he made clear many times, RAF supporting troops .. heresy. Spits for Malta and North Africa? Took the Prime Minister and the War Cabinet and the CGoS to achieve that against bitter RAF opposition.

To give an example of the RAF's 'Colonel Blimps', at the height of the BoA in mid 42 to mid 43, when the Germans were sinking ships faster than the Allies (even including the US) could be built, in Britain where they were living off stocks which were declining (inc fuel) and the food ration was cut again and again. There was just 5 VLR Liberators based in Iceland.... and Portal complained about 'being forced' to allocate them to 'such a useless task'.

Given the importance of the BoA and how he fought so hard to lose it, killing LR Spits was an easy task by comparison. Imagine him lying to Churchill (because he had to know about the P-51B just about to come on stream) in late 43 that 'the long range fighter is impossible', in writing no less. So bad was he that even (the always politically neutral and usually careful not to offend anyone) official war report on the RAF made special mention of his endless opposition to LR fighters.


And that, gentlemen is the real reason why it didn't happen .. and makes the Merlin Mustang even more of a special story. 
Hated by the USAAF at first, tremendous opposition internally, much corporate opposition by other companies. 
An orphan. Only A few people and, very importantly Rolls Royce (without their support it would never have happened .. and they never get the credit they due over this) believed in it and made it happen.
And sheer desperation forced the higher USAAF people to grab it.

To be fair, in the end they grabbed it because the 'higher people' worried (for whatever emotional and political reasons) about the hideous losses their bombers were suffering.


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## fastmongrel (Aug 3, 2013)

Aint it lucky the good old USAAF saved us snaggle toothed Brits from our own incompetence we had been getting our ass whuuped for 4 years. That Portal hey bet he got the Iron Cross 1st class from his buddy Adolf. 

How about we cut him some slack he might have made the wrong call but then name me a military leader who didnt make wrong calls, with the benefit of our 20/20 hindsight glasses we can criticise but we cant stand in the mans shoes and we couldnt make the call with all the info we have today. Portal might well have had legitamate and justified reasons for not wanting Spitfires wandering over Germany, he might have been under orders from above that conflicted with a desire to build LR fighters. 

Just to keep banging on saying Portal killed lots of RAF crew for dogmatic reasons does not work for me.


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## stona (Aug 3, 2013)

There is absolutely no point in comparing different aircraft with different fuel tank arrangements. It is only relevant to compare the performance and handling of a particular mark of Spitfire fitted with and without various tank installations.
In this context the "Mustang" is just a red herring.
Cheers
Steve


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## Edgar Brooks (Aug 3, 2013)

OldSkeptic said:


> Supermarine Spitfire (early Merlin-powered variants) - Wikipedia, the free encyclopedia
> n the Mk I PR Type B (also known as Medium Range (MR)) conversions which followed, the F24 camera lenses were upgraded to an eight inch (203 mm) focal length, giving images up to a third larger in scale. An extra 29 gal (132 l) fuel tank was installed in the rear fuselage. It had been envisaged that much larger cameras would be installed in the fuselage immediately behind the pilot, but at the time RAF engineers believed this would upset the Spitfire's centre of gravity. Cotton was able to demonstrate that by removing lead weights, which had been installed in the extreme rear fuselage to balance the weight of the constant speed propeller units, it was possible to install cameras with longer focal-length lens in the fuselage(1).
> The Type B was the first to dispense with the heavy bullet resistant windscreen. (2)Many of these early PR Spitfires were fitted with the Merlin XII engine and Rotol constant-speed propeller with the early, blunt spinner of the Spitfire Mk II


Which shows the danger of believing everything on the internet (especially on Wiki.)
(1.)  Constant-speed propeller units were not fitted to the Spitfire until July 1940, and Cotton was "relieved of his post" on June 18th., so could not have had anything to do with the C.S. units. V.P. (Variable Pitch, or just two-position) units, quite possibly, but they were quickly made obsolete. The amount of lead removed was 32lbs, around 4 gallons-worth of weight. Remember that Cotton had also already removed the radio, and anything else he considered surplus. It wasn't RAF engineers who advised Cotton against the extra tank, it was a couple of Tedder's technicians; at the time Tedder was Director-General of (the Air Ministry's) Research Development. 
(2) The "Type B" was just the original pair of "Type A" airframes N3069 N3071, which, having been supplied in October 1939, never had the bullet-proof glass fitted in the first place
(it first arrived around the time of Dunkirk (read "Fly For Your Life," in which Stanford Tuck relates how his first glass saved his life, over Dunkirk, on the day that it was fitted.)


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## Mike Williams (Aug 3, 2013)

Edgar Brooks said:


> (1.)  Constant-speed propeller units were not fitted to the Spitfire until July 1940...,
> (2) The "Type B" was just the original pair of "Type A" airframes N3069 N3071, which, having been supplied in October 1939, never had the bullet-proof glass fitted in the first place (it first arrived around the time of Dunkirk (read "Fly For Your Life," in which Stanford Tuck relates how his first glass saved his life, over Dunkirk, on the day that it was fitted.)



Hello Edgar,

A couple of minor quibbles, admittedly not directly related to the thread's central topic. Please see the following regarding constant speed props.

No. 19 Squdron Operations Record Book, 1 November 1939
No. 54 Squadron Operations Record Book, 10 December 1939
Rotol Airscrews for Spitfire, HQ Fighter Command, 16 June 1940
Spitfire Conversion of 2 Pitch De Havilland Airscrews to Constant Speed, HQ Fighter Command, 17 June 1940
Spitfire I fitted with De Havilland Constant Speed Airscrew, 22 June 1940
No. 92 Squadron Operations Record Book, 25 June 1940
No. 609 Squadron Operations Record Book, 26 June 1940
No. 611 Squadron Operations Record Book, 28 June 1940
No. 74 Squadron Operations Record Book, 28 June 1940

Also, Spitfire I N.3171 was delivered 16 November 1939 with a bullet proof windscreen.


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## Edgar Brooks (Aug 3, 2013)

N3171 was a trials aircraft, and had its bullet-proof windscreen fitted 14-2-1940 (Spitfire the History, page 87.)


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## Edgar Brooks (Aug 3, 2013)

OldSkeptic said:


> No reason not to do it with Spits, as said even a Mk V with a 29 gal rear tank and a drop tank could do a 300 mile combat radius missions.


Thank you for making it plain that you have no interest in a discussion (and learning.) Twice you've been told that a rear tank could not be fitted into the Mk.V (and I've found further confirmation, of this, as late as the end of 1942,) and yet you persist in the same tired old nonsense. I see no point in continuing this farce.


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## Aozora (Aug 3, 2013)

Edgar Brooks said:


> Which shows the danger of believing everything on the internet (especially on Wiki.)
> (1.)  Constant-speed propeller units were not fitted to the Spitfire until July 1940, and Cotton was "relieved of his post" on June 18th., so could not have had anything to do with the C.S. units. V.P. (Variable Pitch, or just two-position) units, quite possibly, but they were quickly made obsolete.


 
Wrong - CS Rotol props were fitted to N30 and N31xx serialled Spitfires of 54 and 66 Squadrons in late 1939/early 1940, along with UHF radio units:







KL-O 54 Sqn, possibly N3188 delivered 54 Sqn 21/12/39. Al Deere and Colin Gray both flew Spitfires with CS units over Dunkirk.






Several of the P.R type Bs were conversions of Spitfire Is from the same production batch, and Matusiak 2007, has photos of these aircraft in the book used as a reference.



Edgar Brooks said:


> (2) The "Type B" was just the original pair of "Type A" airframes N3069 N3071, which, having been supplied in October 1939, never had the bullet-proof glass fitted in the first place
> (it first arrived around the time of Dunkirk (read "Fly For Your Life," in which Stanford Tuck relates how his first glass saved his life, over Dunkirk, on the day that it was fitted.)


 
Wrong again. According to Hooton _Spitfire Camouflage 1938-1940_ (Scale Aircraft Modelling, November 1982) fitting of the BP windscreens started in September 1939. eg Spitfires of 611 Sqn photographed during an open day at Digby, _February 1940 (Dr Alfred Price via Scutts)_:






These weren't "trials aircraft", these were standard, operational Spitfire Is.


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## Mike Williams (Aug 4, 2013)

Edgar Brooks said:


> N3171 was a trials aircraft, and had its bullet-proof windscreen fitted 14-2-1940 (Spitfire the History, page 87.)



Hello Edgar,

Spitfire the History got it wrong way round regarding N.3171's windscreen. 






N.3171 first flew on 10 November 1939 and was delivered to Boscombe Down on 16 November 1939. "As delivered, this aeroplane was fitted with a bullet proof windscreen, armour plating over the fuel tank, and a domed top on the sliding hood..." 

Please see Flight, March 28, 1940 for a brief mention of "amoured windscreen" and assorted photos with the bullet proof windscreen in evidence. If you look around a bit there are plently of photos of Spitfires equipped with bullet proof windscreens during the winter of 39/40. I would fully expect that the very early Spits that were delivered with the initial style of windscreen would have been retrofitted prior to Dunkirk, such as the case you mention by Tuck. That's an interesting lead worthy of further research.

Nice post Aozoro!


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## Greyman (Aug 4, 2013)

For what it's worth I have a document from Vickers-Armstrongs Ltd. dated 29 Jul 1939 that indicates that the Spitfire's front armour (windscreen, bulkhead armour, petrol tank sheet) will be introduced into production line on N2023 and subsequent aircraft (due for delivery 15 Aug 39). Also 15 sets per week for retrospective fitting starting 10 Aug 39.


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## Mike Williams (Aug 4, 2013)

Greyman said:


> For what it's worth I have a document from Vickers-Armstrongs Ltd. dated 29 Jul 1939 that indicates that the Spitfire's front armour (windscreen, bulkhead armour, petrol tank sheet) will be introduced into production line on N2023 and subsequent aircraft (due for delivery 15 Aug 39). Also 15 sets per week for retrospective fitting starting 10 Aug 39.



Hello Greyman, That information is worth quite alot from my perspective.  Thanks for sharing! Do you have any information on Spitfire Alteration 1/36 - Armour Plating? No. 41 Squadron's Operations Record Book, 23 November 1939 mentions this modification.


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## Greyman (Aug 4, 2013)

Yes that would be the 'front armour' I mentioned. It seems 41 Squadron got their retrospective sets at that time.


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## Edgar Brooks (Aug 4, 2013)

And modification 36; note date of issue. In the Spitfire Mk.I A.P., there's no mention of windscreen or fuel tank deflection armour modifications prior to April 1940:-


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## Greyman (Aug 4, 2013)

Edgar Brooks said:


> And modification 36; note date of issue. In the Spitfire Mk.I A.P., there's no mention of windscreen or fuel tank deflection armour modifications prior to April 1940:-



You can't go by the dates the modifications are officially listed with reference to when the aircraft actually received said modifications. I had this point driven home to me when researching the Hurricane. Official publication dates for obvious things like metal wings and cannon armament were listed well after they were in service.


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## Greyman (Aug 4, 2013)

Aozora, I'm not the strongest student of all things Spitfire and could be mistaken, but some of those propellers in the images appear to be two-pitch airscrews.


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## F-16 (Aug 4, 2013)

tomo pauk said:


> The Spitfire was one of the best known planes ever, and, especially in the UK, it is still regarded as the best fighter of ww2 by many. However, it was not good in some things: the fuel tankage was modest, even with changes introduced mid-war, and (with Merlin engines, ie. most of the examples produced) it was 'only' as fast as LW opposition, unlike the similarly-engined P-51B/C/D/K.
> So what would be your take: what changes to introduce, in order to push the Merlin Spitfire beyond, say, Ruhr, while gaining some speed (in 20000-35000 ft altitude range, focus being 25-30000 ft) in process? We need the plane to be fielded in May/June 1943 at least.



My favorite WW2 plane! I have a model of it in 1:18. But I thought the Zero was the best overall WW2 fighter: faster diving/climbing? Heard that the Spit has still got many world records?

Maybe a different question, but may feed your topic, I ones met a guy who is a Spitfire collector and owns a huge camera which was installed in a Spitfire during the war, was this the first time that a WW2 plane made photos in flight (spyplane)?


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## Edgar Brooks (Aug 4, 2013)

Greyman said:


> You can't go by the dates the modifications are officially listed with reference to when the aircraft actually received said modifications..


How about the date "cleared" for inclusion on the production line, as written in Vickers' official, original, Spitfire/Seafire modification ledger, at present held in the RAF Museum's library, and which exactly matches that leaflet date?


> Wrong - CS Rotol props were fitted to N30 and N31xx serialled Spitfires of 54 and 66 Squadrons in late 1939/early 1940, along with UHF radio units:


Any Rotol props (and there were very few, in fact Supermarine don't list them) fitted to the Mk.I were 2-position, and standard radios were HF or VHF. Rotols were mostly reserved for the Mk.II, since the Merlin XII had a necked-down shaft capable of taking them.


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## Greyman (Aug 4, 2013)

Edgar Brooks said:


> How about the date "cleared" for inclusion on the production line, as written in Vickers' official, original, Spitfire/Seafire modification ledger, at present held in the RAF Museum's library, and which exactly matches that leaflet date?



Same thing. I ran into a lot of examples with the Wellington too. Those official modification dates don't reflect when the aircraft started seeing them in service (note the image Mike Williams linked in post #249).


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## razor1uk (Aug 4, 2013)

1940 was a franetic time for the RAF and the aircraft establishments, where all available aircraft were used or in readiness in some way, and if not, was being repaired, tested, modded or salvaged.


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## Mike Williams (Aug 4, 2013)

Greyman said:


> You can't go by the dates the modifications are officially listed with reference to when the aircraft actually received said modifications. I had this point driven home to me when researching the Hurricane. Official publication dates for obvious things like metal wings and cannon armament were listed well after they were in service.



Indeed Greyman. That reminds me of another interesting case of a modification being used in service prior to the printed publication date of the mod.

16 February 1940 - 151 Squadron Operations Book, ("100 octane is being used enabling 12 lbs. boost") 

20 March 1940 - A.P.1590B/J.2-W, Merlin II and III - Use of +12 Lb./sq.in. Boost Pressure - Alterations and Precautions


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## Aozora (Aug 4, 2013)

Edgar Brooks said:


> Any Rotol props (and there were very few, in fact Supermarine don't list them) fitted to the Mk.I were 2-position, and standard radios were HF or VHF. Rotols were mostly reserved for the Mk.II, since the Merlin XII had a necked-down shaft capable of taking them.



This doesn't account for the fact that the Merlin III was equipped with a universal prop shaft able to take either de H or Rotol props; nor does your claim about the Merlin XII account for the numerous Merlin III powered Rotol equipped Hurricanes that flew before and during the Battle of Britain. As for the claim about the Rotols being two position?

Flight March 1939: note the final introductory paragraph: "_Today production is concentrated on constant speed airscrews_..."

http://www.flightglobal.com/pdfarchive/view/1939/1939 - 0834.html

Flight May 1940: note the opening sentence "A new airscrew specifically designed for the fast single-engine fighters of the Royal Air Force...and is also in service with the squadrons."

http://www.flightglobal.com/pdfarchive/view/1940/1940 - 1504.html



Greyman said:


> Aozora, I'm not the strongest student of all things Spitfire and could be mistaken, but some of those propellers in the images appear to be two-pitch airscrews.



Hello Greyman; while the 54 Sqn (KL-) Spitfires were fitted with Rotol props, which, btw, seemed to be the 20 deg pitch version described in the 1939 article, the 611 Sqn Spitfires (FY-) were still fitted with the 2 position de H props.

The Flight articles make it clear that Rotol were not manufacturing two speed propellers, which is one reason why there was no need to for a crash conversion program to convert the Rotol props already fitted to Hurricanes to CS. Ergo - _any_ Spitfires fitted with Rotol propellers, including the PR conversions, were fitted with CS units.


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## Greyman (Aug 4, 2013)

Mike Williams said:


> Indeed Greyman. That reminds me of another interesting case of a modification being used in service prior to the printed publication date of the mod.



Combing through some more of my stuff and I have a document from Group Captain Saundby (Director of Operational Requirements) dated 3 Oct 1939 stating that 50% of Spitfires in Fighter Command have been armoured and that the rest are expected to be finished by the end of November. Also that production Spitfires are fitted with armour.

This is all in reference to 'front' armour, mind you (bulkhead, petrol tank sheet, windscreen).


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## OldSkeptic (Aug 4, 2013)

fastmongrel said:


> Just to keep banging on saying Portal killed lots of RAF crew for dogmatic reasons does not work for me.



Oh, the more I study history the more important it seems (to me at least) to understand the people behind the decisions. The 'why', to explain the 'what'.
And that means you have to examine their motivations, attitudes, ideas and ideologies.

This is commonplace in some areas. You can't separate BC's campaign without examining Harris for example.

But Portal doesn't get nearly as much attention as he should. He was at the heart of a lot of the major decisions the RAF made (or backed his subordinates when they made their ones), but since he was the boss he had the responsibility.

Right from the beginning and the appalling way Dowding and Park were treated after the BoB, the 'leaning towards the enemy', the debacle of Coastal Command, Malta, NA, et al. He was at the heart of all the major decisions made. Therefore has to take at least some responsibility.

Plus he had his particular personal prejudices, of which his antipathy towards the LR fighter was just one and that, naturally, affected his decision making and thus tactics, strategy and even personnel selection for the RAF throughout the war.

Therefore you can't select out 'what' the RAF did throughout the war, without looking at the 'who' and the 'why'.

One way of looking at it would by doing a 'thought experiment' and imagine that (say) Portal had been really for a LR fighter and pushed it real hard. What would have happened then? What could have been done and how would that have affected strategy and tactics?

I pick on the LR fighter issue more than some others, because it was a critical variable in virtually every area of air strategy. The lack of it meant all sorts of limitations on what could and couldn't be be done . To take the obvious dependency, no LR fighter, therefore bombers have to fly at night, which means they can't (initially) hit anything, therefore centers of cities is just about all they can (sort of) manage to hit (sometimes) and you need heaps of them to achieve anything. Each of the decisions, post the LR fighter one, is made for you therefore that is the critical one to make.


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## Mike Williams (Aug 4, 2013)

Edgar Brooks said:


> Any Rotol props (and there were very few, in fact Supermarine don't list them) fitted to the Mk.I were 2-position, and standard radios were HF or VHF. Rotols were mostly reserved for the Mk.II, since the Merlin XII had a necked-down shaft capable of taking them.



I'm sorry Edgar but thats incorrect. Please see: 
AP 1565A, Spitfire I Aeroplane, June 1940
Alan Deere, Nine Lives, page 55 
Flight, May 23, 1940: The Latest Rotol Airscrew

Beginning approximately April 1940 the Rotol constant speed props were mostly used on new production Hurricanes and then also the Spitfire II when they entered production. See for example:

W/C Ian Gleed D.F.C., Arise to Conquer, (Random House, New York 1942) pp. 62-63. 
No. 1 Squadron Operations Record Book, 18 April 1940
No. 1 Squadron Operations Record Book, 2 May 1940
Paul Richey DFC, Fighter Pilot (Redwood Press, Wiltshire 1990) p 93.
No. 151 Squadron Operations Record Book, 13 April 1940
No. 151 Squadron Operations Record Book, 15 May 1940
Hugh Halliday, No. 242 Squadron, The Canadian Years, (Canada's Wings, Ontario, 1981). p.78.
Wing Commander Tom Neil, DFC, AFC, AE, Gun Button to 'Fire', (William Kimber, London 1987), pg 48.


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## Aozora (Aug 4, 2013)

For interest, here are the _Flight_ articles on the Rotol propellers from 1939 and 1940:

View attachment Rotol 1939.pdf


View attachment Rotol 1940.pdf


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## razor1uk (Aug 4, 2013)

To be attempt to be a real student/patriot/knowledged person involves if possible learning both/all sides or as much as can be about the good bad ugly and beautful and worse etc, not just a/one bit of something, that leads to being more blind and/or to the dark side of things.


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## Juha (Aug 5, 2013)

Edgar Brooks said:


> Thank you for making it plain that you have no interest in a discussion (and learning.) Twice you've been told that a rear tank could not be fitted into the Mk.V (and I've found further confirmation, of this, as late as the end of 1942,) and yet you persist in the same tired old nonsense. I see no point in continuing this farce.



Again, look Morgan Shacklady p. 149 and also BR202. The rear tank was very rare, but M S, Price and Shores all agreed that the Spit Mk VCs which flew from Gibraltar to Malta during the siege had them, 17 were sent of which 16 arrived to Malta.

Juha


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## Greyman (Aug 5, 2013)

Juha said:


> Again, look Morgan Shacklady p. 149 and also BR202. The rear tank was very rare, but M S, Price and Shores all agreed that the Spit Mk VCs which flew from Gibraltar to Malta during the siege had them, 17 were sent of which 16 arrived to Malta.



Also, the Spitfire V Pilot's Notes mentions a 29 gallon rear fuselage tank.


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## Juha (Aug 5, 2013)

Thanks Greyman, Yes it does. And it also noted that the drop thank should be emptied first, then the rear tank. The 170gal tank can be dropped when empty or in emergency earlier and the fuel in the 29gal rear tank can be used after that. 

Juha


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