# P-51D maneuvrability - what it was in reality ...



## Rapecq (Apr 10, 2007)

Hi 

I've been reflecting on this aspect of P-51 Mustang characteristics and I couldn't get to any reasonable conclusion. I've heard that laminar wing reduced drag, but it will also stall earlier. However, I also read that P51 could turn very sharply and was quite controlable at high speeds.

So guys I would be grateful If someone could enlighten me on P51 maneuvrability (turning, rate of roll, handling at high speeds) in comparison to German Fighters like Fw 190 A or Bf 109G-K.

Regards,


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## FalkeEins (Apr 10, 2007)

..... late model Gs were capable performers and the well armed “Beule” was a easily a match for a Mustang.. in a 1 v 1 turning fight  the P-51 has little chance ..it was heavier and in a tight turn the 109 could gain some height advantage, the pilot also being able to pull harder in the turn by adjusting the angle of incidence of the tailplane... easing off the throttle a little could easily bring the 109 around on the tail of the P-51..

.. Unfortunately for your average 109 pilot the P-51 was rarely encountered alone. 

"...You always had to watch out for the wingmen, which many of us tended to forget. But above all the main thing was, never go into a dive with a Mustang on your tail!.." 

( the above adapted from an account by a III./JG 300 pilot)


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## Hop (Apr 10, 2007)

Have you read the test reports at WWII Aircraft Performance

If you look at the Mustang section, they have an AFDU (British testing unit) comparison of the Mustang III (P-51B/C) against some of its contemporaries.


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## Brain32 (Apr 10, 2007)

Yes that WWII Aircraft Performance site has enourmus amount of very usefull documents  However please keep in mind that all those comparisons are made with captured axis planes in questionable condition and with pilots which were most certanly not as familiar with the planes of their enemy as they were with their planes 

I have some Russian turn time numbers, however condition of both P51 as also the axis planes is again unknown(atleast to me)
Turns were made at 1000m
P51 - 23sec
FW190A8(3900kg) - 21-22sec
BF109G2 - 20-21,6sec

And yes P51 had very light controls at high speeds


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## FLYBOYJ (Apr 10, 2007)

Don't forget - later in the war P-51 drivers had G suits....


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## syscom3 (Apr 10, 2007)

And above all it had speed and a good rate of climb.

Speed = energy = maneuverability


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## Soren (Apr 10, 2007)

Be very careful using the WWIIaircraftperformance site as reference for German fighter performance as it has a habbit of presenting the very lowest of figures obtainable in this area - the author being known for his bias toward Allied a/c. 

Nontheless it is a good source for info on allied a/c, but please draw your conclusion(s) from the originial data available and not from what someone says ! 

As to the P-51 maneuverability, well at low to medium speeds it was clumsy compared to the German fighters while at high speed it could compete.


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## syscom3 (Apr 10, 2007)

Soren said:


> s to the P-51 maneuverability, well at low to medium speeds it was clumsy compared to the German fighters while at high speed it could compete.



You mean the German fighters could compete........... the P51 was 50 mph faster than the -109 and 30 mph than the -190.


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## Udet (Apr 10, 2007)

syscom3 said:


> You mean the German fighters could compete........... the P51 was 50 mph faster than the -109 and 30 mph than the -190.



Sorry syscom but this data is incorrect.

The P-51 D had a maximum speed of 703km/hr at altitude on WEP which could be utilized for a couple of minutes only. No WEP being applied and the maximum speed of the plane is of course lower than that...do you know what the maximum speeds of the 109 G-10 was?

50mph faster than the 109? Where on earth did you get that from?

You are knocking on Kufurst´s door.


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## Kurfürst (Apr 10, 2007)

Rapecq said:


> Hi
> 
> I've been reflecting on this aspect of P-51 Mustang characteristics and I couldn't get to any reasonable conclusion. I've heard that laminar wing reduced drag, but it will also stall earlier. However, I also read that P51 could turn very sharply and was quite controlable at high speeds.
> 
> ...



I would say the pilot's statements on the Mustang's manouveribilty was relative to the previous 8th AAF fighter the flew, which mostly meant the P-47. The 47 was big, and was rather poor at turns with it's great weight and wignloading. The 51 was a big improvement compared to it in this regard. 

In comparison to German fighters, it was fair. It was probably a match to the FW 190 in turns, and rather inferior to the 109 in turns, which is supported by Mark Hanna who flew both. In roll rate, it was completely inferior to the FW 190, and vs the 109 it was a mixed matter. The 51 had excellent roll rates at high speed, whereas the 109 was restricted in this regard, otoh the low speed rolling of the 109 was better. 

Generally the controls of the 51 were light and responsive, a bit like the 190, but it's stall characteristics were not as docile as the 109s or other better behaving fighters.

In speed it was considerably faster than the FW 190A models, and about the same as the Dora-9. The 109s it again depends on model; the early 1943 G-6 models that Allied tests were performed against were of course, much slower. The high altitude 109Gs (/AS models, 109K, G-10) which begun to appear at about the same time as the Mustang were entirely comparable at all altitudes, ie. doing around 690-710 km/h max speed at around 7500 meters, same as the Mustang. Most 40-50 mph accounts are based on British tests with Mustang vs. '109G' and 'FW 190A', but the tested Axis planes were rather old, worn models not representative of the latest types the LW had entering service parallel to the Mustang.

The zoom climb there was little difference, both German models were good at zoom climbs, whereas in the dives the 51 had some advantage. In climbs the 109s easily outmatched it, esp later models, the 190A being about the same, perhaps poorer at altitude, the 190D being better at most altitudes. In dives the accounts are rather mixed,but generally there was not that much difference between WW2 fighters anyway as most would believe in this regard. 

Firepower was a mixed matter. The 190A had clearly outclassed it. The 109G is a matter of taste, as a guideline the USN considered three .50 HMGs equal of one 20mm cannon (and the Germans had the advantage of the best cannon rounds, far better than that of the USN had). The P-51 models had either 4 (early models) or 6 x .50s. The 109s base armament was 1x20mm and 2x13mm HMGs, or about 5 HMGs as per the USN's formula - about the same firepower but in a different package. Generally the 'six-pack' of fifties was sufficient vs fighters, but I'd guess they were in for a headache in they'd have to intercept big bombers. The late MK 108 fitted 109s had an extremely devastating gun at their disposal, but it was somewhat balanced out by it's worse ballistics vs. fighters.

Overall, probably the best desrcription of the Mustang would be a fair, good over-all fighter that's best quality was speed and range, and was not exceedngly great or poor in any other regard. A jack of all trades, master of none.


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## Soundbreaker Welch? (Apr 10, 2007)

Those encounter reports of the Mustang pilots are cool and interesting, even if you can't verify all the kills.


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## Civettone (Apr 10, 2007)

Excellent Kurfürst!

I only disagree that the devestation done by the MK 108 was somewhat balanced out by its worse ballistics. I think the MK 108 had sufficient ballistics for short-range combat and that the disadvantage of its lower MV has been systematically overrated. 


And apparently, in the beginning of 1945 1/3 of the P-51s still had 4 MGs.

Kris


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## FLYBOYJ (Apr 10, 2007)

Civettone said:


> And apparently, in the beginning of 1945 1/3 of the P-51s still had 4 MGs.
> 
> Kris



That was a pilot option which allowed 400 rounds per gun.


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## lesofprimus (Apr 10, 2007)

The pilots who had the use of the Mk 108 were amazed at its destructive power, as u guys know... The MV was almost irrelevant, as they only used it inclose, ranging the target/bomber with the MGs prior to launching a salvo...


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## GregP (Apr 10, 2007)

P-47 D: Empty: 10,605 lbs; Loaded: 17,411 lbs; Engine: 2,500 HP; Wing Area: 300.3 sq. ft.; Power Loading: 7.0 lbs per HP, Wing Loading: 58.0 lbs per sq ft

P-51D: Empty: 7,639 lbs; Loaded: 11,095 lbs; Engine: 1,475 HP; Wing Area: 233.0 sq ft; Power Loading: 6.5 lbs per HP; Wing Loading: 47.6 lbs per sq ft

Bf 109 G-6: Empty: 5,895 lbs; Loaded: 6,942 lbs; Engine: 1,475 HP; Wing Area: 174.0 sq ft; Power Loading: 4.7 lbs per HP; Wing Loading: 39.9 lbs per sq ft

Spitfire Mk IX: Empty: 4,972 lbs; Loaded: 7,357 lbs; Engine: 1,585 HP; Wing Area: 242.0 sq ft; Power Loading: 4.6 lbs per HP; Wing Loading: 30.4 lbs per sq ft

P-38J: Empty: 14,107 lbs; Loaded: 21,612 lbs; Engines: 2,850 HP; Wing Area: 328.3 sq ft; Power Loading: 5.5 lbs per HP; Wing Loading: 53.3 lbs per sq ft

Fw 190 A3: Empty: 7,053 lbs; Loaded: 8,580 lbs; Engine: 1,700 HP; Wing Area: 197.0 sq ft; Power Loading: 5.0 lbs per HP; Wing Loading: 43.6 lbs per sq ft

The “loadings” above are calculated at Normal Loaded Weight. Most planes never fought at normal loaded weight, particularly the Allies since they had to burn fuel just to GET to the fight. Also, Allied fighters would routinely drop ordnance and/or drop tank before a dogfight.

From the above, the most maneuverable based on wing loading at Normal Loaded Weight would be the Spitfire Mk IX. Of course, things OTHER than wing loading, particularly the choice and cleanliness of the airfoil, affect maneuverability. A dirty airplane was not as good a turner as a clean one, everything else being equal.

The best climber, based purely on power loading, would be the Bf 109 G-6. Again, things other than power loading, particularly the propeller choice and the altitude curve of the supercharger / turbocharger, affect rate of climb.

The Mustang in particular was a very good zoom climber, using momentum to trade speed for height. At faster speeds it could easily out-zoom the Bf 109, but the Bf 109 was better in a sustained climb. Dogfights NEVER involve a sustained climb. Conversely, the Mustang had a relatively high “stick force per g,” being in the 25 – 30 pounds per g range at normal center of gravity. So, it was mostly a 3 – 4 g airplane except for emergencies. If the Mustang happened to be fighting at 8,500 lbs, it was very equal to the Bf 109 in all categories, and the Bf 109 had a MUCH smaller fuel fraction, so it was probably much closer to the normal loaded weight than a Mustang that had just flown 500 miles and had dropped tanks and burned fuel from the fuselage tanks.

A few other points: The Bf 109 had no rudder trim and was very tiring to the pilot when out of trim. The other planes did not have this difficulty. The Bf 109’s control became VERY heavy at high speeds, making it very much of a “straight line” fighter at 400+ mph, while it was VERY maneuverable at 250 – 300 mph. Hence, the Bf 109 pilot wanted to get the fight slow while the Mustang pilot wanted speed. Similar things can be said for the Spitfire, though not nearly to the degree of the Bf 109.

So … we a re back at the question of exactly HOW to compare the aircraft?

All were good, and we are unlikely to arrive at a "best" since it is 65+ years since WWII and we are still debating it.


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## FalkeEins (Apr 11, 2007)

Kurfürst said:


> Overall, probably the best desrcription of the Mustang would be a fair, good over-all fighter that's best quality was speed and range, and was not exceedngly great or poor in any other regard. A jack of all trades, master of none.




...thats got to be the worst description I ever read about the P-51 !!


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## lesofprimus (Apr 11, 2007)

LMAO...


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## Parmigiano (Apr 11, 2007)

Just one technical questio: we always evaluate aircraft engines by power, but there are other parameters, i.e. torque and related power curve.

Is torque directly impacting the performances? For instance providing better acceleration etc.

Now it seems likely that engines with higher displacement may have an higher and better distributed torque, so the 27 liters Merlin should have less torque than a 36 litres DB605, that should be 'worse' than the 44 litres BMW801 that should give in to the big P&W and Wright radials

Is there any documentation of torque measurement for this engines?


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## Hop (Apr 11, 2007)

Torque = (horsepower x 5252) / rpm

Because the prop acts like a continuously variable transmission, meaning the engine doesn't alter speed much at maximum power, torque isn't that useful a figure for aero engines.


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## FLYBOYJ (Apr 11, 2007)

Hop said:


> Torque = (horsepower x 5252) / rpm
> 
> Because the prop acts like a continuously variable transmission, meaning the engine doesn't alter speed much at maximum power, torque isn't that useful a figure for aero engines.


Great explanation but torque isn't that useful for "recip" aero engines - it’s VERY important with regards to turboprops.


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## DerAdlerIstGelandet (Apr 11, 2007)

GregP said:


> P-47 D: Empty: 10,605 lbs; Loaded: 17,411 lbs; Engine: 2,500 HP; Wing Area: 300.3 sq. ft.; Power Loading: 7.0 lbs per HP, Wing Loading: 58.0 lbs per sq ft
> 
> P-51D: Empty: 7,639 lbs; Loaded: 11,095 lbs; Engine: 1,475 HP; Wing Area: 233.0 sq ft; Power Loading: 6.5 lbs per HP; Wing Loading: 47.6 lbs per sq ft
> 
> ...




Very good post and I enjoyed reading that, thanks. I too agree that it is too hard to describe what is "best" because all of the top aircraft here that we are talking about Spit, Bf 109, Fw 190, P-51D, and P-47 all had there advantages and disadvantages over each other. They were all great aircraft...


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## FalkeEins (Apr 11, 2007)

".. but the Bf 109 was better in a sustained climb. Dogfights NEVER involve a sustained climb..."

.. as I pointed out in my first post ...109 pilots were specifically instructed to ' climb for the sun' to escape the P-51...never to dive with it.. 

"..the Bf 109 pilot wanted to get the fight slow while the Mustang pilot wanted speed.." 

again this was alluded to in the comments of the JG 300 pilot reproduced above...pulling tighter and tighter turns by modifying the angle of incidence of the tailplane...


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## Udet (Apr 11, 2007)

FalkeEins said:


> ...thats got to be the worst description I ever read about the P-51 !!



Falke...i believe it would be much better if you could explain the reasons behind this comment.


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## FalkeEins (Apr 11, 2007)

..I would have thought that was obvious...

most enthusiasts would probably assert - if pushed - that the P-51 was the fighter that 'won the war', wouldn't they ....lets face it, it did what it did 700 miles from home...'jack of all trades, master of none' has a slightly disparaging undertone in English...I doubt many would agree with the comment that it was only a 'fair' performer either .....all in all, a rather obtuse assessment ...


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## syscom3 (Apr 11, 2007)

The P51's range for a single engine fighter was the best of the ETO.

Its 6 .50's were more than adaquate to shoot up fighters. 

Its top speed was the fastest untill the final models of the -190's and -152 took to the sky in the waning months of the war.

I'd say it was master in a few catagories, good in some, and taken together, it was the finest combination of all up to Feb 1945.


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## renrich (Apr 11, 2007)

The difficulties in trying to evaluate WW2 fighters are many fold. For instance: at what altitude? how far from base? was the German fighter hampered by armament for shooting down bombers? how about survivability? If you are talking about a dogfight 500 miles from your base then you probably have to give the edge to the P51. Unless you are including the TA152, if you are talking about fighting above 25000 feet, then the P47 gets the nod. If you are talking about shooting down 4 engined bombers then the BFs and FWs probably have an edge particularly over the P51B-C. If you are talking about the fighter-bomber role then the FW and P47 have it all over the P51 and BF109. If somehow I was given my choice of any fighter to fly over Europe in in WW2 and I wanted to feel real good about coming back home I would take the P47 as long as it had the range for the job. I would use strictly energy tactics and I would rely on that rugged airframe, good armor and reliable, damage resistant engine to bring me home. And I would only fight at high altitudes.


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## Soundbreaker Welch? (Apr 11, 2007)

A Mustang might buck you off, while a Thunderbolt just scares you.


Meaning, you have less to fear from the P-47 when you're the pilot.


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## Udet (Apr 11, 2007)

FalkeEins said:


> ..I would have thought that was obvious...
> 
> most enthusiasts would probably assert - if pushed - that the P-51 was the fighter that 'won the war', wouldn't they ....lets face it, it did what it did 700 miles from home...'jack of all trades, master of none' has a slightly disparaging undertone in English...I doubt many would agree with the comment that it was only a 'fair' performer either .....all in all, a rather obtuse assessment ...



What might be obvious to you might not be so to others. 

Also that you apparently belong in a group of thinkers who assert the P-51 "won the war" does not mean there will be many others -me included- who will be more than happy to counter such assertions; such a thing would mean your doubts are incorrect.


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## mad_max (Apr 11, 2007)

I would say master at some, average at others and jack of all trades pretty much
describes why the P-51 did what it did. I always sigh when someone posts with a preconceived
idea; when in reality they don't have a clue how these aircraft matched up.

Even though there are flying examples of most WWII fighters we'll never know what really
they could and couldn't do in real life. For some strange reason the owners just don't
want to beat the sheat out of them. 

We only have feelings on what we *THINK they'd be. To folks that like the Spit;
they under estimate the 109/190/macchi. The 109 guys do the same about the pony.

We can't trust pilot accounts as we know not the circumstances. One Allied pilot will
say one thing and another will say just the opposite. Same for the Axis.

For example:

"The best fighters I met in combat were the American P-51 Mustang and Russian Yak-9U. Both of those types obviously exceeded all Bf109 variants in performance, including the 'K'. The Mustang was unmatched in altitude performance, while the Yak-9U was champion in rate of climb and maneuverability."

- Luftwaffe Pilot Walter Wolfrum (137 victories)*


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## davparlr (Apr 11, 2007)

GregP said:


> P-47 D: Empty: 10,605 lbs; Loaded: 17,411 lbs; Engine: 2,500 HP; Wing Area: 300.3 sq. ft.; Power Loading: 7.0 lbs per HP, Wing Loading: 58.0 lbs per sq ft
> 
> P-51D: Empty: 7,639 lbs; Loaded: 11,095 lbs; Engine: 1,475 HP; Wing Area: 233.0 sq ft; Power Loading: 6.5 lbs per HP; Wing Loading: 47.6 lbs per sq ft
> 
> ...



I have issues with the way aircraft are compared in this way, which was noted by GregP. Typically, US aircraft are penalized for having a large load lifting ability. I think that there are two valid methods for comparing aircraft in load values associated with maneuvering. First is at similar combat capabilities, i.e., empty weight plus similar armament loads and similar fuel for equal combat times. The other is probable combat weight, e.g., P-51 with no drop tanks and empty aft tank, Bf-109 with three quarters to half gas. The method using loaded weight meets neither criteria. Here is the comparison of loads.

P-47D - 6746 lbs
P-51D - 3456 lbs
Bf-109G - 1047 lbs
Spit IX - 2385 lbs
P-38J - 7505 lbs
Fw-190A-3 - 1527 lbs

As can be noted, US aircraft have a much greater load carrying capacity than other combatants. This load carrying capability paid off nicely over the skies of Germany and in the Pacific.

My favorite method is to use empty weight in comparisons, since fuel load and armament are generally equivalent and the ratios would tend to be constant as combat weights increased, except for the P-38 where fuel consumption would require more loaded weight.

Let's not punish the aircraft for being able to carry more load.


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## FalkeEins (Apr 11, 2007)

Udet said:


> ..Also that you apparently belong in a group of thinkers who assert the P-51 "won the war" does not mean there will be many others -me included- who will be more than happy to counter such assertions; such a thing would mean your doubts are incorrect.



...actually I suppose I might go for the Spitfire as the fighter that won the war..but you know what, it wasn't the D-9 or Ta 152 .....they were on the losing side of course....but all that is another discussion...

MM, not sure what you mean by ' we don't know what they'd do in real life....' ?? Thats precisely why I would place a certain value on a pilot's account, especially one that had been in a life or death struggle against the aircraft in question ...!!


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## mad_max (Apr 11, 2007)

Udet posted


> The P-51 D had a maximum speed of 703km/hr at altitude on WEP which could be utilized for a couple of minutes only.



Ahh where you get this? The cooling system is good for 80" of boost. Also 67"
is the WEP rating until mid June 1944 in the ETO. After that period it's 72" for
USAF and 75" in the Brits squads. Also higher boost was used in the Pacific.
WEP has been used for up to 45 mins in real life. The 5 min. max doesn't mean
she'd puke at that point. That time period was for a good engine check when you
made it back to base.

davparlr's post is well thought out and should be taken seriously.

Soren posted:



> Be very careful using the WWIIaircraftperformance site as reference for German fighter performance as it has a habbit of presenting the very lowest of figures obtainable in this area - the author being known for his bias toward Allied a/c.
> 
> Nontheless it is a good source for info on allied a/c, but please draw your conclusion(s) from the originial data available and not from what someone says !



You are correct. It has great references for the pony and spit. Best to draw
your own conclusions no doubt. Same on the other guy's axis pages.

Best.


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## mad_max (Apr 11, 2007)

FalkeEins,

It's not so hard to understand. At no time were the Pony and 109 ever pitted
against each other with both in pristine condition. (mechanical or perfect
exterior finish). In battle the conditions for both are never equal. One usually
has one or more advantage. Surprise, higher energy state, not running at
factory specs. amongst other variables. Remember the saying "Huns in the
Sun".

This idea of what was better turning, faster, dives better, etc. just can't be
determined. No way...no how.

Best,


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## davparlr (Apr 11, 2007)

syscom3 said:


> The P51's range for a single engine fighter was the best of the ETO.
> 
> Its 6 .50's were more than adaquate to shoot up fighters.
> 
> ...



I agree with this entry. The P-51 was a first line fighter and provided its pilot with tools to defeat the enemy if used properly, namely great speed at all altitudes, very good high altitude performance, superb diving ability, adequate low level performance, and adequate armament. Other first line fighters, both enemy and friend, also provided tools to defeat its enemy, if used properly. The greatness of the P-51 was, that it could do this after flying four hours and hundreds of miles.

The only comment to the above is that the Fw-190D-9, which appeared in late '44 was clearly superior to the P-51D (not so much the P-51B) up to 25,000 ft.


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## mkloby (Apr 11, 2007)

FLYBOYJ said:


> Great explanation but torque isn't that useful for "recip" aero engines - it’s VERY important with regards to turboprops.



I was just about to say that. Engine output is commonly measured in ft-lbs of torque. We use SHP = .00019 x prop rpm x torque


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## FLYBOYJ (Apr 11, 2007)

mkloby said:


> I was just about to say that. Engine output is commonly measured in ft-lbs of torque. We use SHP = .00019 x prop rpm x torque



We're psychic friends dude...


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## mkloby (Apr 11, 2007)

FLYBOYJ said:


> We're psychic friends dude...



Haha ... a little creepy... but funny


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## Udet (Apr 11, 2007)

Mad Max, you have to believe me, the data did not come to me through the Grimm´s Fairy Tales.

I have consulted several books, articles and also people who know about this; 45 minutes using WEP? Do you mind if i ask you the same question you asked me?

I am of course open to receive new information, but 45 minutes running on WEP....


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## Udet (Apr 11, 2007)

FalkeEins said:


> ...actually I suppose I might go for the Spitfire as the fighter that won the war..but you know what, it wasn't the D-9 or Ta 152 .....they were on the losing side of course....but all that is another discussion...



To have such a blooming attitude that was rather a poor argument. Spitfire, lovely choice. Congratulations.


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## mad_max (Apr 12, 2007)

Guess you don't have _FIGHTING MUSTANG_ by William N. Hess. Pages 27-29.


That's just one book that I had handy. Grant it after that I would want a VERY
good engine check. Probably would want it replaced in fact. Just as I would want
the same done whatever airframe (allied or axis).

BTW 703 km/h is for 61" boost which is Military power not WEP. WEP was 67"
until they started using 100/150 fuel, then it went up as posted above. Understand
though The FT height at 67" will be lower than for 61" and it will even lower for 72".

Want a good reference for the P-51 then grab this one.
AbeBooks: Search Results - gruenhagen


To get the performance after the 100/150 or 115/145 fuel then you need to get the docs. Mike's site has them.

My choice would be Fw-190 if I flew Axis or the P-51 for Allied.

Best,


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## Erich (Apr 12, 2007)

since you guys have mentioned the performance charts on the net then please also visit the P-51 pilot accts as well and read them all ! The Stang did what it did and the 109's/Fw's tried. Clearly the Allies had the upper hand in control of the skies over the Reich had it been even keel then it would of been interesting but that is all what - if's isn't it ?


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## Smokey (Apr 12, 2007)

I have heard that the octane rating of allied fuel was different to axis fuel. Did anyone test axis planes with allied fuel after the war or were the axis engines not geared for allied fuel?


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## GregP (Apr 12, 2007)

A point to make here. It was stated, quite correctly, that it was tough to tell by asking pilots.

Let's examine that.

Let's take a American pilot who was trained in the U.S.A. and then was posted to Europe flying P-51's. And let's say he has lived and flown 15 missions. The P-51 is his sum total fighter experience and he is till alive, so the P-51 is "tops!"

Talk to a British Spitfire pilot and the Spitfire is "tops."

Talk to a German and whichever of the main fighters HE was assigned to was "tops."

Then we have people like Capt. Eric Brown of the RAF who flew more different types than any other test pilot. He may or may not have been a normal squardron pilot, and so may or may not have been in air combat. If he WAS in air combat, my bet is that he was mostly in one type of fighter. That is, he probably didn't do a tour in Spits followwed by a tour in Hurricanes followed by a tour in Tronados followed by a tour in Mustangs.

When test flying, the test pilot rarely achieves complete knowledge of the flight characteristics of the type. He is much more concerned with flight at the edges of the performance envlope. That is, top speed, best rate of climb, best angle of climb, stall speed, max speed in a dive, etc.

So ... I contend we'll never reach a consensus of which was the best.

The Mustang had some great characteristics and I am American, so I like it. I still don't think it was quite the dogfighter that the Spitfire was and didn't have the armament of an Fw 190. If usually had an edge in SOME area against almost any opponent and that edge was used by the Mustang drivers to win fights.

The same can be said of La-5's, Yak-3's, Fw 190's, Bf 109's, etc.

It is a TOUGH thing to pick a "best" when all the designers were striving for that exact thing, and all were coming very close!

The fun is in the trying!

I volunteer at a museum every weekend taht flies WWII warbirds every week. We fly Mustangs more often than most, but that is because we have more spare Mustang parts than any other parts. We only fly the P-47G about once or twice a year, and the Spitfires (a Mk IX and a Mk XIV) are privately owned and fly when the owner wahts them to fly. Our P-38 flies 5 - 10 times per year depending on what is happening, and the P-40 flies more than most others.

these are all old fighters in civilian hands and we don't fly them at the edges of the performance envelope, so we'd NEVER know which was the best when pushed to the limits because we don't push them to the limits on purpose!

It makes these threads all the more fun!Cheers to you.


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## davparlr (Apr 12, 2007)

GregP said:


> A point to make here. It was stated, quite correctly, that it was tough to tell by asking pilots.
> 
> Let's examine that.
> 
> ...



Chino??


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## syscom3 (Apr 12, 2007)

Yeah..... You from Chino?


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## Soundbreaker Welch? (Apr 12, 2007)

Unless this chart is wrong, the FW190-A has a far wider turning circle than the Mustang P-51C. I don't know if the P-51D kept as tight a turn as this or if the canopy and tail stabilizer made it more sluggish.
Probably it still would have outturned an FW190-A, unless at low altitudes like the Russian test shows.

This test does not list the Bf 109. It's turn rate would probably be alongside the Spitfire.







Comparitive Performance of Fighter Aircraft


This test, if accurate, shows why the Tempest is not as highly regarded I thought it could be.

And good post Greg.


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## GregP (Apr 12, 2007)

Hi guys,

Actually I live in Irvine but, yes, I volunteer at the Planes of Fame Mueum in Chino, California, U.S.A. We have a LOT of volunteers!

A couple of weeks ago, we had TWO P-38's in the air at the same time! We had our own "23 Skidoo" (P-38J) and "Glacier Girl" (P-38F) flying together! It was magic. Earlier in the year, the first Saturday in January actually, we had a Spitfire Mk IX, Mustangs, P-40N, F8F, two AD Sjyraiders, a big-engine T-28, and several other warbirds all flying on the same day! It was a great photo op, to say the least.

An R-3350 makes a wonderful sound at startup ...

We are currently restoring a Bell P-59A Airacomet to flying status and it SHOULD fly around the end of the year, at which time it will be the world's oldest flying jet aircraft. I am not currently working on it, but it is progressing well thanks to some very qualified volunteers.

We will also have our Northrop M9MB Flying Wing back running at about the same time (working on a blown cylinder on the port Franklin engine).

For you Brits out there, we have a Meteor but no engines for it, a Vampire (not sure of status ...), and a flyable Folland Gnat among other types. Our Spitfires include a Mk IX, a Mk XIV, plus a flyable Hurricane, and a Grumman F6F in British markings.

Our Mitsubishi A6M5 Zero is the only one in the world still flying on the original Japanese Sakae engine, and it flies every so often. We have an original Shusui rocket palne, but you'd have to go a LONG way to find anyone who actually wanted to fly it! So, we do not have it in flyable condition.

We also have a static Mitsubishi J2M Raiden. We WOULD like to fly it, but the wing spar has too much corrosion and we really don't want to fabricate a new wing spar. As an aside, our Bell P39 has the same problem ... corroded wing spar plus many missing parts. The wing spar is the big ticket item.

Our Warhawk is a P-40N and it flies regularly. The P-47 is a "G" model built by Curtiss. It should fly this coming Saturday as well as at the annual airshow in mid May. Our B-25 flies regularly. We have a flyable Grumman F3F, F4F, soon a flyable TBD Avenger, and one of the few flying Douglas Dauntlesses.

We also have a flyable Boeing P-25 Peashooter and a Seversky AT-12 Guardian (export version of the P-35).

In the jet area, we have two flyable F-86 Sabres, a flyable MiG-15, a flyable PZL TS-11 Iskra and a Lockheed T-33 that is used to start the Reno air races every year. Out MiG-21 is "flyable" but doesn't fly at this time.

In unflyable state we have a MiG-17, Douglas Skyrocket, a P-80 (no engine) and F9F Panther (no engine), a Ryan Fireball (piston installed but no jet). These are the hangared jets. 

In outside storage we have quite a few older jets including F8 Crusader, F-104 Starfighter, A Thunderflash that was part of the FICON project and still has the trapeze hook on it, a standard F-84F, some A-4 Skyhawks, an F-100 and a few others.

Our B-17 is the one used in the Movie "12 O'Clock High" as "Picadilly Lilly" and only needs money to fly again ... anyone have a spare $1.4M? At the rate we are cashing in pop cans, we'll have the funds for the B-17 in only 7,652 years!

More planes but a bad memory coupled with a few beers ... so, all for now.

Cheers!

If you are anywhere NEAR Southern California, U.S.A. next month, our airshow is right in the middle of the month of May and almost all the flyable planes will fly. Stop in and have some fun!

If you show up, ask for me, Greg Pascal and I'd love to help you have a good visit.

Here are a few images:





Mitsubishi Raiden ... Nice looking! Looks very aggressive ...






100% Scale Wood Mockup of a Heinkel He-100D! Rare .... only one, in fact! Quick! Snap some pics for the propaganda department ... wait, repaint the number first ...





A6M5 Zero with Original Sakae Engine ... sounds sweet!





Boeing P-26 Peashooter .. and it FLIES! .. as long as you can get someone to volunteer to wind up the inertia starter ...





Business End of a Spitfire XIV. Maybe not quite enough propeller blades? Needs 2 - 3 more? Nnahhhh ...





Northrop N9MB Flying Wing ... back flying again about the end of the year! Need to fix an engine.


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## GregP (Apr 12, 2007)

I also wanted to comment on the turning circle chart above. What a piece of wartime propaganda!

In a level turn at a particular speed and "g" loading, all aircraft turn with the same radius. A "3 g" turn is a 3-g turn if both aircraft are at, say, 250 knots.

The important curve is the "g-availble" curve. Since the Spitfire had a lower wing loading than most of its opponents, it could pull more "g" without stalling, and so could turn tighter, but at the cost of higher g-loading.

The turning circle chart makes it appear as though the Spitfire could turn tighter easily as a matter of course, but tThat is true ONLY if the Spit driver is pulling more g's and is only one aspect of dogfighting.

The other aspects are altitude of the engagement, rate of roll, instantaneous and sustained rate of turn - both are important, armament, available "emergency power," the current traiing level of the pilot (can THIS pilot fly it at the edge of stall?), and last but not least ... range. 

You might well ask, "What in blazes has RANGE to do with it?"

Ask any Messerschmitt pilot over Great Britain. He KNEW he only had maybe 15 - 20 minutes of flying time over England, and LESS if he was in a dogfight due to higher power settings. MANY were lost in the channel trying to get home after "stretching" a dogfight, sometimes with no real alternative to it except to get shot down if he broke out of the fight at the wrong time.

Another possible factor might be how many pints of Ale the pilot had the night before ... and whether or not he smoked (interferes with breathing at altitude ... and pulling g's is hard work!).

Just pointing out the obvious ... I'm sure the members in here KNOW all that without my post, but the turning circle graph is only accurate at one altitude, one speed, and one level of "g." Any change alters the chart.


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## mkloby (Apr 13, 2007)

Excellent pics, Greg. I particularly liked the He 100! Think you could get some from other angles???


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## Soundbreaker Welch? (Apr 13, 2007)

> What a piece of wartime propaganda!



Thanks.  



> In a level turn at a particular speed and "g" loading, all aircraft turn with the same radius.



So a Spitfire and Boeing 747 are actually turning exactly the same, except that since the Spitfire is smaller it appears to be turning tighter?

Wouldn't the Boeing have more problems with air pressure, slower speed, and heaviness turning on the same radius as the Spitfire? 

I'm really don't know what I'm talking about.


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## Hop (Apr 13, 2007)

> I also wanted to comment on the turning circle chart above. What a piece of wartime propaganda!



It's actually a post war piece from T S Wade, former head of the AFDU.



> The important curve is the "g-availble" curve. Since the Spitfire had a lower wing loading than most of its opponents, it could pull more "g" without stalling, and so could turn tighter, but at the cost of higher g-loading.
> 
> The turning circle chart makes it appear as though the Spitfire could turn tighter easily as a matter of course, but tThat is true ONLY if the Spit driver is pulling more g's and is only one aspect of dogfighting.



It's also true about sustained turns. The diagram is meant to show overall turning performance, though.


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## lesofprimus (Apr 13, 2007)

> It's also true about sustained turns. The diagram is meant to show overall turning performance, though


.And not very well I might add.... Those kind of diagrams suck and do nothing more than incorrectly inform the general public....


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## bryce (Apr 13, 2007)

Soren said:


> Be very careful using the WWIIaircraftperformance site as reference for German fighter performance as it has a habbit of presenting the very lowest of figures obtainable in this area - the author being known for his bias toward Allied a/c.
> 
> Nontheless it is a good source for info on allied a/c, but please draw your conclusion(s) from the originial data available and not from what someone says !
> 
> As to the P-51 maneuverability, well at low to medium speeds it was clumsy compared to the German fighters while at high speed it could compete.



If we ignore the German aircraft in this diagram, can we take this as a good comparison of the Allied aircrafts turning circles on this table then?

http://www.wwiiaircraftperformance.org/wade-turning.jpg


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## mad_max (Apr 13, 2007)

It's pretty hard to get anything out of that diagram to be honest. I've never
seen any description of the "test" parameters that should accompany a chart
like this.

This is my thoughts from years of reading, studing documents, data, pilots
accounts, etc. It may not be what some want to hear, but in my honest
opinion this is what I've come to the conclusion of.

Best bet is to figure the spits to the spit XIV, P-51's, 109's, 190's to be real
close to each other in the 10 - 20K range in altitude at a speed of around 200
- 300 mph. The jug would at 250+ be able to hang, but under 250 it better
dive out and run.

Over 25k the P-51 and Jug will have an upper hand. Over 32k and the Jug is
the one to beat.

At lower altitudes under 8k the Spit and 190 would be close with the 109
alittle wider.

See there is just to many variables to say this airframe out turned that one
and no reliable tests have been done in the past. We sure won't have them
done in today's age.

Taking everything into account....the old adage...It's the Pilot not the aircraft
has lots of merit to it. 

Best,


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## GregP (Apr 13, 2007)

Tell you what ... when I go there tomorrow, I'll try to get a few shots of the He-100D from several angles. Maybe post next week after I doctor and upload to PhotoBucket. Most of our German stuuf are 100% replicas, but the Fiesler Storch and the He-162 are real. The only reason the Storch isn't flying is lack of a working Argus V-8 engine. The rest of the airframe is ready to fly right now.

We also have a real Horten Ho.IV glider ... see below: (the elevons are off the wing being worked on ...)







I'll also try to get a shot of our P-47G starting up with smoke and spinning prop blades ... we'll see ...


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## GregP (Apr 13, 2007)

Hey Mr. Soundbreaker Welch (love that handle!),

Yes, a Spitfire and a Boeing 747 will fly the exact same radius level turn if both are at the same speed and pulling the same g ... a 2g turn is a 2g turn and will have the same radius if flown at the same speed.

Most Boeing 747's try to never get to a 45° bank because the paying passengers get upset about it ... 

Also, a 747 looks like a lumbering giant though it will easily outspeed any Spitfire. It also has a considerably higher ceiling and hauls more than TWICE as much fuel! 

Ha ha ha ha ...

It probably hauls an entire squadron's worth of Spitfires in fuel, include the Spitfire airframes, pilots, drop tanks, crew chiefs, and squadron vehicles ... but that's another story.

Cheers!


For those who like numbers I offer the following.

1) In a level turn, the g load can be figured as 1 / cosine of the angle. For a 60° angle, the g = 2.

2) The stall speed increases as the square root of the g load.

3) In a level turn, the radius of turn equals the square of the velocity divided by the value of g times the tangent of the bank angle. 

How does this help?

Suppose we have a Spitfire that stalls at 80 mph in level flight. Further suppose we are in a 60° bank. The cosine of 60° is 0.5 (one half). 1 divided by 0.5 = 2, so we will be flying in a 2g turn. The square root of 2 is 1.414, so our new stall speed is 1.414 time 80 mph, or 113.13 mph.

Further, suppose we are not the best pilot in the world, so we need a 10% margin to avoid a stall. 110% of 113.13 mph is 124.45 mph.

OK, so we want to know the radius of turn of the Spitfire flying at 124.45 mph while banking at 60° and pulling 2g.

The tangent of 60° is 1.732 .

124.45 mph is 182.5 feet per second. Square 182.5 and divide by (32.174 * 1.732) to get a turn radius of 598 feet. (the value of 1 g is 32.174 feet per second squared).

Notice there is no calculation for wing loading. We have only speed and angle of bank or g load. 

How does this help the question?

Well, a lower wing loading means a lower stall speed. So, the radius of turn decreases as the square of the stall speed.

Finally, let's make a comparison.

Suppose we have a Spitfire that is stressed for 8g and it has a level flight stall speed of 80 mph.

We pit the Spitfire against an Fw 190D that is also stressed for 8g but it has a level flight stall speed of 85 mph.

Suppose we want to have a level flight turning battle between tehse two aircraft (would WE want that?). Further, suppose we want both planes to have a 10% buffer in speed.

Spitfire: 80 mph + 10% = 88.0 mph. Now, suppose we pull 8g. The stall speed will be 248.9 mph. The radius of turn is 521.8 feet.

Fw 190D: 85 mph + 10% = 93.5 mph. Now, suppose we pull 8g. The stall speed will be 264.46 mph and the turn radius will be 589.1 feet.


Doesn't seem like much of a difference, and it isn't. But the Spitfire can turn inside the Fw while traveling 16 mph slower. That means the Spitfire can gain a lead and get bullet into the Fw at this close-to-maximum performance, assuming a good starting position.

In the reverse situation, the Spitfire can get away for the same reason ... assuming the very competent German doesn't hit the Spit with a single cannon round first, thus decreasing the Spit's performance critically ... and maybe fatally.

Not much of a difference, but please remember I made up these numbers. I don't KNOW the level flight stall speed of the Spit or the Fw and I don't know the design load factor either. I doubt seriously if either could pull 8g. 

A Mustang has a stick-force-per-g of about 30 pounds. To pull 8g, the pilot would have to apply 240 pounds of force in pulling the stick. Remember he is sitting down in the seat, not standing braced for a pull, and he has been in a VERY cold cockpit for hours and is no doubt stiff, sore, and cold ... at least in WWII Europe. For a modern airshow, he is probably well conditioned, comfortable, just swallowed some Gatorade, and is ready to pull quickly and hard.

For the case of a wartime Mustang, 4g is more likely.

The point is, if the speed is the same and the g load is the same, the turn radius will be the same.


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## Soundbreaker Welch? (Apr 14, 2007)

I got a quite a bit of what you were saying. And thanks for noticing my odd name! 

Basically, the chart is wrong in that all the aircraft are going in a 45 degree angle, thus pulling the same g's, but the chart makes the false impression that some aircraft aren't turning as well or as much when in fact they all are. 

Though a Spitfire going at a 45 degree angle can turn tighter than a FW-190A going at a 45 degree angle, but it's not because the FW is turning less, It's because the FW can't stall as slow as the Spitfire. It's higher speed makes it turn wider. So no matter how fast or slow the FW is going, the Spitfire will always turn slower than it and thus come on the inside. 

Thanks. I'll study your points more to understand them even better.

By that way, I had no idea that there was still a surving Horten Ho. That's really cool. Too bad nobody flies it. But then somebody might crash it and then no more Horten Ho on display for the world.


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## Mike Williams (Apr 14, 2007)

Hi guys:

The Air Fighting Development Unit (AFDU) based at Wittering and Duxford was under the control of Fighter Command and the Air Ministry where it conducted comparative trials and developed and promulgated tactics effective against the enemy. Jeffrey Quill, Chief Test Pilot for Supermarine, wrote that the "Air Fighting Development Unit represented Fighter Command and […]did a most useful job in relating the various British fighters to those of the enemy and in developing tactics on behalf of the command."

The author of Comparative Performance of Fighter Aircraft, Sqdn. Ldr. T.S. Wade, D.F.C, A.F.C, R.A.F.V.R., had served as O.C. Flying at the AFDU. Those charts appear to be a product of AFDU evaluations.

The relevant portions from Wade’s article relating to this thread’s current direction are summarized below:

[…]What follows is intended to give the average non-technically minded reader some idea of how some of these aircraft compare with each other in the matter of performance and manoeuvrability.

Comparison does not mean obtaining results from an indiscriminate dogfight between two fighter types, but a practical assessment of the information gained as a result of specific tests in specific circumstances. These circumstances are standardized by dividing the tests up into two categories, namely, Factual Comparison, which includes speed, rate of climb, range, endurance and acceleration, readily measured against the stop watch, and Competitive Comparison, such as turning circles, rates or roll and dive zoom climbs. Rates of roll, of course be measured either way. The choice is a matter of opinion. 

Turning Circles

In circumstances where the ability to turn quickly or tightly are infinitely variable, and where two aircraft are nearly the same, such as the Tempest V and Thunderbolt II, a great deal depends on the ability of the pilots. Speed must be taken into account if the results are going to be of any real value. 

For example, if a Tempest dives on a Thunderbolt with an overtaking speed of only 50 mph, the Thunderbolt will easily be able to avoid the attack by turning, although at the same speed in the hands of equally competent pilots, the Tempest will outmanoeuvre the Thunderbolt. This advantage, however, is no by any means so apparent at high altitudes, due to the greater engine efficiency of the Thunderbolt above 25,000ft. 

Similarly, where low-altitude and high-altitude fighters are compared any advantage shown by the former will be reduced as the high-altitude fighter gets nearer to its best operational altitude. *After taking all these considerations into account, the position of the aircraft relative to each other will be seen from the diagram.* 

Once again, the Spitfire maintains top place, followed by the Mustang, Meteor, Tempest and Thunderbolt. Too much regard to this order should not be paid, particularly by the individual who will angrily recall the occasion when he out-turned a Meteor when flying his Tempest. This sort of thing is inevitable, but we can only repeat that _where the circumstances are common to both aircraft, these positions are not far wrong. (my emphasis) _​
Before smearing S/L Wade with comments such as “wartime propaganda”, “biased”, “the chart is wrong in that all the aircraft are going in a 45 degree angle”, it might be beneficial to read to read more closely what he wrote and note the context in which his conclusions were reached.

My opinion is that the article is interesting when viewed as a pilot’s reflections (who happened to head up the trials) on what the comparative tests revealed.

With regards to the main thread subject of P-51 maneuverability; I have many/most of the wartime performance and comparative trials on the type which when taken together paint a fairly clear picture of the P-51’s performance capabilities. I find the performance curves to most efficiently impart information such as level speed and climb. It must be said, however, that I had a completely different sense of flying the aircraft in combat and a _feeling_ for how it performed after having read through all the Encounter Reports.

Its one thing for a Technical Report to state: 

“The airplane is very maneuverable with excellent controllability at all speeds up to slightly over 400 MPH indicated, the highest speeds attained in level flight. Stability is good about all axes, and recovery from stalls is normal. The airplane has a fairly short radius of turn and an excellent rate of roll.”​That’s useful and informative.

Tactical Trials further add to our understading with statements such as: 

”The Mustang III is very similar to fly and land as the Mustang 1. It is therefore delightfully easy to handle. It is as easy to fly as a Spitfire IX with the exception that the rudder is needed whenever changing bank…”​
It’s a whole other ballgame, however, when you read a  pilot’s Encounter Report such as that of Lt. Richard D. Bishop wherein he recorded: 


"I’ll never worry about meeting a FW 190 in a 51 since I was able to outturn, outdive and generally out-maneuver him at all altitudes, from 23,000 feet to the deck; I could follow him in anything and do a lot more besides.”​

Read a couple hundred of these P-51 Encounter Reports, go ahead – set aside a few hours and do it, you won’t regret the time spent - you can’t help but be impressed with the P-51’s capability.

Mike


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## davparlr (Apr 14, 2007)

GregP said:


> Suppose we want to have a level flight turning battle between tehse two aircraft (would WE want that?). Further, suppose we want both planes to have a 10% buffer in speed.
> 
> Spitfire: 80 mph + 10% = 88.0 mph. Now, suppose we pull 8g. The stall speed will be 248.9 mph. The radius of turn is 521.8 feet.
> 
> Fw 190D: 85 mph + 10% = 93.5 mph. Now, suppose we pull 8g. The stall speed will be 264.46 mph and the turn radius will be 589.1 feet.



I enjoyed your discussion on turn performance. It demonstrates the difficulty in comparing turning performance. It also shows the impact of wingloading on turn performance and is a good estimate for aircraft performance given similar airfoil designs. Soren has justifiable argued that wingloading discrepancy is somewhat offset by efficient airfoil design, as in the Ta-152 vs P-51H. Turn performance has a lot variables, many difficult to get a grasp on, especially old aircraft with little data.

On your example, I suspect that a WWII pilot pulling 8gs without a g suit would be in La La land. But the example was informative.




Mike Williams said:


> Read a couple of hundred of these P-51 Encounter Reports, go ahead – set aside a few hours and do it, you won’t regret the time spent - you can’t help but be impressed with the P-51’s capability.



I agree with this. As noted in the "Report on Joint Fighter Conference", the P-51 was not selected as best fighter above 25k ft or the best fighter below 25k ft but it was selected as 2nd best in both. To me this says that the P-51 may not be the greatest in all situations but was very good in just about all situations and was the greatest in some, particularly in long range escort. All in all, it was a fine aircraft in which the pilots typically were proud to fly and were confident in its ability, much like many other aircraft in the war.


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## Rapecq (Apr 14, 2007)

Hi

So after this which has *Mike Williams* presented us, I'm a little confused about real P-51 capabilities ... 


> The airplane is very maneuverable with excellent controllability at all speeds up to slightly over 400 MPH indicated, the highest speeds attained in level flight. Stability is good about all axes, and recovery from stalls is normal. The airplane has a fairly short radius of turn and an excellent rate of roll.”



But this description reffers to P-51B. Does "D" have also excellent controllability and rate of roll?? And I have also one more question: why Bf 109 was difficult to controll at high speeds ??



Regards


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## Erich (Apr 14, 2007)

gents I already mentioned reading the the pilot accts on page # 3 and indeed everyone needs to stop and spend today having a ball reading these. I have taken several of these and called up several living 356th fg pilots whose official version I read to them to confirm, in most cases the pilots have these accts in their still records and it has been interesting to get a second point of coverage even if the memory cannot meet all the details of years ago. some things just stick after 61-62 years like glue


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## GregP (Apr 14, 2007)

There are several reasons for the Bf 109 being harder to control at higher speeds and all were correctable. Just two of the reasons were as follows:

1) The aircraft had no rudder trim and the pilot would tire of keeping pressure on the rudder at speeds higher or lower than the trimmed speed.

2) The mechanical advantage of the control stick was smaller than some others and the stick force required to roll and pitch at higher speeds required a lot of strength ... while the fuselage and canopy area were small and did not allow much room for the pilot to move around and get some extra leverage on the stick.

Hence, a tough to maneuver aircraft. I emphasize that this was only at higher speeds. At 250 - 310 mph, the Bf 109 was superb. Then again, so was a Zero at those speeds!

A rudder trim would have been easy to add and the mechanical arm could have been altered ... but they didn't for some reason. Our museum has a Spanish Casa being put back into flying condition and the cockpit is VERY snall. Still no rudder trim! And this was post-war!


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## mkloby (Apr 14, 2007)

GregP said:


> There are several reasons for the Bf 109 being harder to control at higher speeds and all were correctable. Just two of the reasons were as follows:
> 
> 1) The aircraft had no rudder trim and the pilot would tire of keeping pressure on the rudder at speeds higher or lower than the trimmed speed.



If the A/C has no rudder trim, then how could there be a trimmed speed w/ regard to the rudder? Are you referring to a factory set trim tab, or are you referring to other control surfaces?


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## GregP (Apr 14, 2007)

There is always a need for rudder pressure when accelerating. One at a particular speed and in cruising flight, there is a speed where no rudder presure is required. It is usually set with a ground-adjustable tab but, in the case of the Bf 109, the vertical fin was not symmetric. It was airfoiled to fly straight at a "trimmed" speed. 

Not sure what that speed WAS, but I assume it was near the natural cruising speed. This probably puts it at about 260 - 280 mph, right slap dab in the middle of it best maneuverability envelope.

If cruising faster or slower the pilot had to maintain rudder pressure in one direction or the other. If accelerating or decelerating, same story.


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## mkloby (Apr 14, 2007)

GregP said:


> There is always a need for rudder pressure when accelerating. One at a particular speed and in cruising flight, there is a speed where no rudder presure is required. It is usually set with a ground-adjustable tab but, in the case of the Bf 109, the vertical fin was not symmetric. It was airfoiled to fly straight at a "trimmed" speed.
> 
> Not sure what that speed WAS, but I assume it was near the natural cruising speed. This probably puts it at about 260 - 280 mph, right slap dab in the middle of it best maneuverability envelope.
> 
> If cruising faster or slower the pilot had to maintain rudder pressure in one direction or the other. If accelerating or decelerating, same story.



Good info. I didn't know the vert stab wasn't symmetric. I understand control surfaces and all, but I wasn't sure if it had a ground preset tab, or what exactly you were referring to. Trim is more complicated than just based off airspeed. Control surface(and hence trim) inputs are based off airspeed, acceleration, and power.

On clockwise spinning single engine birds, if you increase power, you will first need right rudder (and also forward pressure on the stick/yoke). The opposite holds true for a power reduction. If you are accelerating, you will initially need left rudder (forward stick) to stay level and balanced.

Of course, when you increase power, the right rudder needed initially is greatest at slow airspeeds, and as you accelerate, the amount of right rudder needed will decrease.


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## Soundbreaker Welch? (Apr 25, 2007)

Mustang Encounter Reports.
http://www.spitfireperformance.com/mustang/combat-reports/4-schlegel-8april44.jpg

Here is what 1st Lt. Albert L. Schlegel had to say on 8 April 1944



> I was flying Green One in Greenbelt Squadron. We were on course and on time when the bombers called for help. We headed south and joined them, finding them quite happy.






What? Doesn't that sound funny?


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## Rapecq (Apr 27, 2007)

Hi

I'm not sure if that is true but I read that for example in Fw 190 push-rods were used for the controls instead of cables - and that's why Fw 190 easy to control even at high speed.
And therefore I have questions: how did those push-rods work (hydraulic)?? and what was the situation of controls support in Bf 109 ... 

Regards,


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## GregP (Apr 27, 2007)

Pushrods and Heim joints are much more fun to fly than cables. The culprit is "cable stretch." Pushrods don't stretch and feel much more "solid."

Most WWII fighters had cable-controlled rudders. Many had all cable controls. Some had pushrods for aileron / elevator and cable rudders.

Some had pushrods from the cockpit to the wing junction, and cables from there to the aileron.

A really neat modern example is the nanchang CJ-6.

It has a cable operated rudder, but the ailerons and elevator are pushrod operated. It flies extremely well. I think better than a Bonanza, which is all cable operated.

Go find one in your area and beg or buy a ride in it!


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## Rapecq (Apr 28, 2007)

Hi

From:
Flying the Bf 109: Two experts give their reports Flight Journal - Find Articles
about Bf 109:

"*When you maneuver above 500km/h, two hands are required for a more aggressive performance. Either that or get on the trimmer to help. Despite this heavying up, it is still quite easy to get 5G at these speeds.*"

"*I like the airplane, and with familiarity, I think it will give most of the Allied fighters I have flown a hard time-particularly in a close, hard-turning, low-speed dogfight.*"

"*It will definitely out-maneuver a P-51 in this type of fight because the roll rate and slow-speed characteristics are much better. The Spitfire, on the other hand, is more of a problem for the 109, and I feel it is a superior close-in fighter*"

and onother one:
"*At higher speeds, the P-51 is definitely superior, and provided the Mustang kept its energy up and refused to dogfight, it would be relatively safe against the 109*."

One small question: why Bf 109 become heavy controllable at high speeds, while for example P-51 or Fw 190 doesn't have such problems ... ??


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## FLYBOYJ (Apr 28, 2007)

Rapecq said:


> One small question: why Bf 109 become heavy controllable at high speeds, while for example P-51 or Fw 190 doesn't have such problems ... ??




The size of the controls, the method of rigging and the way the control system was designed to induce a "balance" within the control system.


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## GregP (Apr 28, 2007)

The P-51 is quite heavy in pitch. According to accounts, it has a stick force per "g" of about 25 - 30 piounds per g, depending on the particular aircraft. You CAN make it turn hard, but you have to pull quite hard to do so. fortunately, the seating position allows you do do this. In roll, the P-51 is MUCH easier at 400 mph than a Bf 109. The culprit is mechanical advantage.

For the Bf 109, the mechanical advantage was not enough for higher speeds, which were not in Messerschmitt's mind as normal maneuvering speeds when the Bf 109 was designed, particularly in roll. Later Bf 109s were fitted with a taller stick to give extra leverage when the real problem could have been solved by moving the fulcrum of the control stick. Unfortunately it would have interrupted the production line right when Germany could not afford to have that happen.

Same with the P-51. The stick force per g COULD have been fixed, but only at the cost of an interrupted production line. Not in the cards. After the war, used in peacetime, there was no need to relieve the stick force since the attention of the various air forces was focused clearly on jets, and not improving older piston-engined fighters currently in service.

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## mkloby (May 1, 2007)

Good info greg


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## Kurfürst (May 2, 2007)

GregP said:


> For the Bf 109, the mechanical advantage was not enough for higher speeds, which were not in Messerschmitt's mind as normal maneuvering speeds when the Bf 109 was designed, particularly in roll. Later Bf 109s were fitted with a taller stick to give extra leverage when the real problem could have been solved by moving the fulcrum of the control stick. Unfortunately it would have interrupted the production line right when Germany could not afford to have that happen.



I don't think it's generally a problem with the stick - the 109 in fact (at least from F version onwards, probably on the E, too) used exactly the same stick as the FW 190, the KG 13 control coloumn. The 109Fs stick could be deflected 15 degrees each side and was .47 meter high in total - you can calculate the deflection path from that easily. The aileron linkage was provided by push rods, just as on the 190. I believe stickforces probably resulted from the aileron's design itself, but then it should be noted u to the maximum level speed of the aircraft, there were no problems with the roll rate of the aircrafts (it began to decline due to stickforces at faster speeds than achievable in level speed), unless you were in a high speed dive. However, most aircraft had restrictions imposed on the pilots not to use ailerons too much in dives for structural concerns, so this might have been intentional. Some later 109s however, from late 1943 onwards, has been fitted with aileron flettner tabs which greatly reduced stickforces at high deflection, allowing 2/3s deflection even at Mach .70 +.

The notion about the small stick travel probably stems from the British early evaluation of the 109E, but they probably refused it because they used (rather funny) types of sticks, which however had much less leverage because only the upper portion of the stick actually moved. I guess it's just a simply case of 'not invented here'.


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## GregP (May 7, 2007)

The Me 109 may well have used the same stick. You can't calculate anything from that unless you have the fulcrum distance ... and you don't seem to have it.

The aerodynamic loads are due to aileron design considerations, airspeed load, and fulcrum. The pilot, in such a small space as a Bf 109 cockpit, sould only supply so much side force for roll. It wasn't enough to give decent roll response above 350 mph or so, at least in the Bf 109 ... and the later models were considerably faster than that, so your statement above doesn't hold up, according to history.

As for the Fw 190, the fulcrum, aerodynamic design, or cockpit leverage position were enough better to compensate. It could do aileron rolls that would tear the wings off the opposition, but wasn't too good at either instaneous or sustained turn rate. The Spitfire was great at turn rate, but was a slow roller.

Take your pick. Either can be better, depending on the pilot and the tactics.

Sorry, but late war Me 109 designs did NOT correct the roll problems, Fletner tabs notwithstanding. It was then and remains now a bad roller at high speeds.

So, the Spitfire was better than the Bf 109 when rolling at higher speeds, was always equal ro better at turn rate, and remained that way until the end of the series. I'd give the nod to the Bf 109 for armament (one in the fuselage is worth two in the wings any day). Neither of them could even come close to a P-40 at 350 mph under 15,000 feet since it rolled more than twice as fast at that speed and altitude thah either of them. Neither could come close to a P-38J or P-38L either in roll but, by that time, the war was lost by the Germans anyway, so it really didn't matter.

The history I have read by William Green, Eric Brown, and many other says the Bf / Me 109's were great airplanes, but were NEVER fast rollers at high speeds, and none mentions any significant improvements in my references. In fact, they all state quite categorically that the Bf / Me 109 was traveling in a straight line when over 400 mph and there was nothing the pilot could do about it except slow down and turn ... if he was able to do so, that is.

Vertical dives are NOT conducive to slowing down, and many went into the ground at high speed in dives.


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## Soren (May 9, 2007)

> It could do aileron rolls that would tear the wings off the opposition, but wasn't too good at either instaneous or sustained turn rate.



I don't hope you seriously believe that..

And as to the controllability of the 109 at high speeds, well you desperately need to read something other than those Allied reports - German and Finnish pilots have repeatedly pointed out that the a/c didn't become hard to control until ca.750 km/h. Pull-outs at 750 km/h was not a problem.


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## GregP (May 9, 2007)

I seriously believe that about the Fw 190. When I hear the same thing once or twice, I may doubt it. Ten pilot reports saying the same thing get my attention. The Ta-152 turned quite well at high altitudes, but was extremely vulnerable to "regular" Allied fighters at lower altitudes ... and it had to get through the lower altitudes while ascending and descending from height. So, all we had to do was wait on it and it would come to us eventually ... same as the Me 262 and Me 163 did. Kill 'em when they land ...

I have read extensively on the Bf 109, not just William Green. All of the Allied testing I have read (including Russian tests) points to a general stiffening at anything over 350 mph, becomming almost rigid at 400 mph and above. All also indicated the Bf 109 to be excellent at 220 to 330 mph, right where it was designed to be.

That comes from multiple sources, all pilot reports I might add, and is confirmed by pilot reports from Merlin-engined Spanish 109s as well. As it happens, we have one of these at the Planes of Fame Museum in Chino, California, U.S.A. . It is being repaired after a brake failure-induced ground loop. In fact, it should be back on its own landing gear in about a month or so and should fly again around the end of the year or so. The Merlin is ready. We need it back on the gear, and some minor sheet metal repair on a wing tip. Then, all we really need is a propeller!

I have to tell you, there is not much room in the cockpit to get leverage for rolling moves. It is simply very SMALL in there!

I spend almost every weekend with WWII aircraft, mostly fighters. If I have a question, I ask the pilots that fly them every weekend. They usually know except for questions about armament. The United States FAA as well as the government really hates it if we shoot down civil aircraft while testing armament for a magazine article ... so we try very hard to avoid that. 

One of the best ways to avoid it is to disarm the old fighters. Works every time! No more "down in flames ..." around here! And we have fewer wrecked aircraft on the ground to clean up after! Truly a win-win solution to the devilish problem of armament tests in civil warbirds.

It is true we don't have an airworthy Fw 190 but, then again, neither does anyone else except for a "new build" Fw 190A with a Russian Shvetsov radial in it (maybe we'll see a pilot report sometime soon ...). We DO, however, regularly fly T-6s, Spitfires (Mk IX and Mk XIV), a P-40N Warhawk, an A6M5 Zero, several types of P-51 Mustangs including a P-51B and d TF-51, F8F Bearcat, F6F Hellcat, F4F Wildcat, a P-38J Lightning, and occasionally an F3F, Hurricane, P-26 Peashooter, P-47 Thunderbolt, TBD Avenger, and SBD Dauntless. The jets also fly semi-regularly (T-33, F-86, MiG-15, TS-11). Sometimes we get a bomber up, too (B-25J).

Frequent visitors include a couple of AD-1 Skyraiders. Their R-3350 engines make an almost impossibly good-sounding rumble when running. Remember not to stand behind it at startup or you'll be rolling down the asphalt as you tumble away from the old warhorse while eating oil smoke at the same time.


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## Parmigiano (May 10, 2007)

GregP said:


> ... Kill 'em when they land ...



.. well, that's valid for any aircraft.

Take an F15 in landing approach, gear and flaps out and no fuel left and let an average pilot bounce it with a P51, Fw190, Spit or any decently fast and armed prop fighter... 

About limit performances of WW2 planes, I am afraid we will always be stuck to non conclusive discussions based on historical reports: nobody will fly a preserved 109 to her dive limits today, like nobody will race a preserved Ferrari GTO (value= $5 million) to find what really was her lap limit at Le Mans.
And even if it will happen, the engines and setup of the preserved machines will never be as 'shiny' as when they were readied for combat or real race.

There is contradictory literature about the 109 high speed performances, some say it was nearly impossible to control at high speed, some other that the 109 dived away from P51 and recovered faster.

What seems probable is that in many cases the real performances were so close that pilot skills and the specific plane could make the difference. (planes were accepted in service with tolerances higher than 5% from standard, so a 95% 109 and a 105% P51 duel was different than a 105% 109 vs 95% P51)


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## Kurfürst (May 10, 2007)

GregP said:


> The Me 109 may well have used the same stick. You can't calculate anything from that unless you have the fulcrum distance ... and you don't seem to have it.



Sorry if you haven't got it, but I already gave you the particulars.

The stick is 47 cms long, and can be deflected to 15.3-15.3 degrees to each side. From that the top of the stick travel can be easily calculated via simple application of trigonometry..



> The aerodynamic loads are due to aileron design considerations, airspeed load, and fulcrum. The pilot, in such a small space as a Bf 109 cockpit, sould only supply so much side force for roll. It wasn't enough to give decent roll response above 350 mph or so, at least in the Bf 109 ...
> 
> 
> 
> ...


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## Glider (May 10, 2007)

Kurfürst said:


> Overall, probably the best desrcription of the Mustang would be a fair, good over-all fighter that's best quality was speed and range, and was not exceedngly great or poor in any other regard. A jack of all trades, master of none.



Totally agree with this.


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## Juha (May 10, 2007)

Soren
What I have read on Finnish pilots opinions on Bf 109G, they tended to agree with Kyösti Karhila, FAF ace with 33 ¼ victories, whose opinion was follow:
virtualpilots.fi: WW2History-KyostiKarhilaInterview.html

Interviewer: How difficult was it to control the 109 in high velocities, 600 kmh and above? 
Karhila: “The control column was as stiff as it had been fastened with tape, you could not use the ailerons. Yet you could control the plane.” 

IMHO a better translation is … You don’t have strength to move ailerons much…

Original answer in Finnish:
Sauva oli jäykkä niin kuin se olisi teipattu kiinni, ei siinä jaksanut paljon siivekkeitä käyttää. Pystyi kuitenkin ohjaamaan konetta. 

Juha


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## Soren (May 10, 2007)

You're a joke GregP..

The 109's wings could take up to 13 G !!



GregP said:


> I seriously believe that about the Fw 190. When I hear the same thing once or twice, I may doubt it. Ten pilot reports saying the same thing get my attention.



I'd like to see all ten please.



> The Ta-152 turned quite well at high altitudes, but was extremely vulnerable to "regular" Allied fighters at lower altitudes ...



That is so very untrue, and just shows how little you really know on the subject ! 

The Ta-152H pretty much proved itself invincible at low altitude, aqcuiring an 11 to 0 kill ratio ! And the pilots who flew the bird all made it quite clear that there was NO allied fighter they couldn't out-maneuver or out-run.

The Ta-152H didn't just turn excellently at high altitude, compared to other fighters it turned even better at low alt. The no.1 recommendation given to the Ta-152H pilots was infact to turn fight the enemy fighters, the high AR wings providing very high lift and very little drag in turns.



> and it had to get through the lower altitudes while ascending and descending from height. So, all we had to do was wait on it and it would come to us eventually



Again you know nothing of what you're talking about GregP... The Ta-152H only fought at low altitude during WW2, so please go another place to spread your lies.



> ... same as the Me 262 and Me 163 did. Kill 'em when they land ...



Oh brother, you're comparing a prop fighter to these ? 



> I have read extensively on the Bf 109, not just William Green. All of the Allied testing I have read (including Russian tests) points to a general stiffening at anything over 350 mph, becomming almost rigid at 400 mph and above. All also indicated the Bf 109 to be excellent at 220 to 330 mph, right where it was designed to be.



Again you rely on the dubious Allied test reports.

Infact the P-51 had greater issues with its elevators than the Bf-109 ever did:

*Robert C. Curtis - P-51 Pilot:*
_My flight chased 12 109s south of Vienna. They climbed and we followed, unable to close on them. At 38,000 feet I fired a long burst at one of them from at least a 1000 yards, and saw some strikes. It rolled over and dived and I followed but soon reached compressibility with severe buffeting of the tail and loss of elevator control. I slowed my plane and regained control, but the 109 got away. 
On two other occasions ME 109s got away from me because the P 51d could not stay with them in a high-speed dive. At 525-550 mph the plane would start to porpoise uncontrollably and had to be slowed to regain control._

*Thomas L. Hayes - P-51 Pilot:*
_Thomas L. Hayes, Jr. recalled diving after a fleeing Me-109G until both aircraft neared the sound barrier and their controls locked. Both pilots took measures to slow down, but to Hayes' astonishment, the Me-109 was the first to pull out of its dive. As he belatedly regained control of his Mustang, Hayes was grateful that the German pilot chose to quit while he was ahead and fly home instead of taking advantage of Hayes' momentary helplessness._

Finnish pilots;

*Kyösti Karhila, Finnish Bf-109 pilot:*
_The Messerschmitt became stiff to steer not until the speed exceeded 700kmh. The control column was as stiff as it had been fastened with tape, you could not use the ailerons. Yet you could control the plane."_

*Väinö Pokela, Finnish Bf-109 pilot:* 
_"-Many claim that the MT becomes stiff as hell in a dive, difficult to bring up in high speed, the controls lock up? 
Nnnooo, they don't lock up. 
It was usually because you exceeded diving speed limits. Guys didn't remember you shouldn't let it go over. 
The controls don't lock up, they become stiffer of course but don't lock. And of course you couldn't straighten up (shows a 'straightening' from a dive directly up) like an arrow."_

The dive speed limit of the 109 is 750 km/h !



> That comes from multiple sources, all pilot reports I might add, and is confirmed by pilot reports from Merlin-engined Spanish 109s as well.



Oh I would so like to hear it personally from their mouths, esp. since I've talked to so many of them !


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## GregP (May 11, 2007)

Hi Parmigiano! Well said!

About the stick length ... it does not matter how long the stick is; it matters where the fulcrum is. You need to know the length of stick UNDER the pivot point (specifically, the length to the cable or pushrod attachment point) as well as ABOVE the pivot point. If you want a technical discussion ... you should not have missed that. Leverage means a ratio, not a stick length.

Sorry, but even German references state the Bf 109's characteristics at above 400 mph. Maybe you are reading Luft46, where they think EVERYTHING German was the best in the world and still, to this day, cannot understand reality? Sorry Kurfurst, your arguments just don't hold up to the facts as I read them but you are, of course, certainly entitled to your opinions as am I mine.

As for Soren, where should I start?

I don't believe I ever said the Bf 109 would collapse at any particular g-force. In fact, I didn't mention g-force ... you did. In total, the Bf 109 was a great fighter.

As for the much-vaunted Ta-152, they only made 67 of them in the entire war! How big an effect could they possibly have? The first production prototype was tested in January 1943, but they didn't make any production planes until 21 November 1944, and only completed ten Ta-152H-1's by the war's end. The rest were a mixed bag of prototypes.

Yeah ... BIG effect in the war. Tell me about it. They're gonna' shoot down the Allied Air Forces with 67 fighters, many of which were unserviceable on any given day?

I don't follow that. These same guys who vaunt the Ta-152 as the "best of the best" refuse to consider the P-51H or the P-47M. We built more than 67 of BOTH before the war ended ...

You can read pilot reports as well as I can. Go to Google, type Bf 109 or Me 109 and read. I bet you can do it; I did. And I compared that with my own library, which is decent if not library sized. They almost all say the same thing.

Basically, they say the Bf 109 and the Spitfire were very closely matched over the entire war, with each having some better characteristics than the other at any particular time. After the Bf 109F, it got heavier and had almost viscious handling characteristics at lower speeds. 

Despite that, the Germans made more Me 109Gs than any other type. I can respect that. They were desperate and losing the war. 

The Me 109 COULD NOT have been a bad fighter. It was the most-produced fighter ever in history and that says a lot about it. But it DID have its bad pionts and that's where I firmly disagree with the diehard Messerschmitt fans. They all seem, like you, to think it had no faults, and that just isn't so. It DID have faults, as did ALL fighters produced by all manufactureres of all sides and nationalities. There was NO fighter that was best at everything.

If we can agree on THAT, maybe we can find out our real differences and go from there?

I'll forego insults if you will, your joke comment aside.

So getting back to reality, the German fighters had faults. You mentioned 700 kph, which is 435 mph. Yes, the Bf 109 could be pulled out of a dive at that speed, IF there was enough altitude. It was not a thing a German pilot would have done on purpose at much faster a speed.

Hhmmmmm ... let's see, how about if I quote two of the greastest German Aces? Would that suffice?

1) ...Nicknamed Gustav, the BF 109G was well armed but not as light as the earlier E and F versions. Its more powerful engine meant higher power settings whose inital climb rate sent it soaring to 18,700 ft. in six minutes but at low speed the plane was difficult to handle. ...Most of us considered the 109G over-developed. Poor landing characteristics added to its woes. 

Jill Amadio, Günther Rall: a memoir, (Tangmere Productions, Santa Ana, CA), pp. 148, 242.

2) The Malta Spitfires are back again... They're fitted with a high altitude supercharger and at anything over twenty-five thousand feet they just play cat and mouse with us. 
At 28,000 feet the Spitfire could turn in an astonishingly narrow radius. We on the other hand, in the thin air of those altitudes had to carry out every maneuver with caution and at full power so as not to lose control. 

Johannes Steinhoff, Messerschmitts Over Sicily, (Stackpole Books, 2004), pp. 97-98, 111.

The above quotes were from 1942 - 1943 timeframe. Why don't we agree to disagree? ... and let it go at that.

I'll give you this much, the German Messerschmitt Me 109 and Fw 190 series were two of the finest fighters built in the WWII era. 

There were others equally deserving of the same statement, and that can be said of American, British, Soviet, Italian, and Japanese aircraft.


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## Soren (May 11, 2007)

Spare me the backpaddling GregP, either you're making up stuff along the way or you're just hanging on to old and dispelled myths.

And about Günther Rall, well he never flew the 109 to the edge after a near death experience early in his carrier - something which has been explained countless times. And as to Steinhoff, well this gentleman has unfortunately been misqouted many times in order to promote other a/c, and most often falsly. 

I can give you plenty of quotes which say exactly the opposite of what you have said GregP, and funny enough is the fact that these can be proven - which I btw will be happy to do for you ?


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## Kurfürst (May 11, 2007)

GregP said:


> Sorry, but even German references state the Bf 109's characteristics at above 400 mph.



'German references' we've never saw, and neither did you, probably... hot air.



GregP said:


> Sorry Kurfurst, your arguments just don't hold up to the facts as I read them but you are, of course, certainly entitled to your opinions as am I mine.



You have no facts to argue with, basically. Basically I base my opinion on the wartime German trials, of which I have copies - several thousend pages of reports and stuff on the Bf 109, not popular books or revisionist sites.



GregP said:


> After the Bf 109F, it got heavier and had almost viscious handling characteristics at lower speeds.



Hogwash. One of the pilots who flew it has to say this on the 109F successor ..

_"He flew only the Bf 109G, of which he said:

It was very manoeuverable, and it was easy to handle. It speeded up very fast, if you dived a little. And in the acrobatics manoeuver, you could spin with the 109, and go very easy out of the spin. The only problems occurred during take-off. It had a strong engine, and a small, narrow-tread undercarriage. If you took off too fast it would turn [roll] ninety degrees away. We lost a lot of pilots in take-offs. "_

As for the weight increase arguement, it's hypocritic. All fighters took up weight during their development - the 109 less than many others. Compare early war 'Bolts, Mustangs, Spits to late war models please...



GregP said:


> So getting back to reality, the German fighters had faults. You mentioned 700 kph, which is 435 mph. Yes, the Bf 109 could be pulled out of a dive at that speed, IF there was enough altitude. It was not a thing a German pilot would have done on purpose at much faster a speed.



British reports on test flying a 109F showed that at 420 mph IAS, to qoute them, 'fairly tight turns were still possible'. Doesn't sounds like there was a special problem pulling out, now does it? 

Mind you, 420 mph* IAS* is very near or at higher altitudes, it's even above the 109's redline speed. Basically it means the aircraft could be pulled up 'fairly tightly' from dives up to the maximum allowed speed. It did require phyisical effort, but was possible without much ado, and the stickforce also prevented the pilot from overstressing the airframe or blacking himself out with fatal results during the pullout. The RAF otoh found in 1940 and 41 that great many Spitfire Is and Vs simply broke up in the pullout because the elevator stick force was so light, the pilot could far too easily apply so much force that was just too much for him and the airframe to bear.



GregP said:


> Hhmmmmm ... let's see, how about if I quote two of the greastest German Aces? Would that suffice?
> 
> 1) ...Nicknamed Gustav, the BF 109G was well armed but not as light as the earlier E and F versions. Its more powerful engine meant higher power settings whose inital climb rate sent it soaring to 18,700 ft. in six minutes but at low speed the plane was difficult to handle. ...Most of us considered the 109G over-developed. Poor landing characteristics added to its woes.
> 
> Jill Amadio, Günther Rall: a memoir, (Tangmere Productions, Santa Ana, CA), pp. 148, 242.



That appears to be the words of Jill Amadio, not Günther Rall. I don't know any LW aces names 'Jill Amadio'. He is a writer, repeating popular aviation books as a side issue in a biographical work.



GregP said:


> 2) The Malta Spitfires are back again... They're fitted with a high altitude supercharger and at anything over twenty-five thousand feet they just play cat and mouse with us.
> At 28,000 feet the Spitfire could turn in an astonishingly narrow radius. We on the other hand, in the thin air of those altitudes had to carry out every maneuver with caution and at full power so as not to lose control.
> 
> Johannes Steinhoff, Messerschmitts Over Sicily, (Stackpole Books, 2004), pp. 97-98, 111.



LOL, a pure copy-paste affair from spitliarperformance dot com. 

Well perhaps you should post the whole quote in it's context, instead of manipulating it. A few pages back Steinhoff mentions he was briefed by the local CO of the unit about the experiences on arrival, who gossiped that lately there are some new Spits had extended wings - these must have been Mk VIIs or VIIIs which had extended wingspan for high altitudes and Merlin 61s. 

Nothing extraordinary there, the unit equipped with normal altitude fighters (G-6s at the time I believe) met with some specialized, low production number high altitude fighters with high altitude engines and extended wignspan. And they found that, amazingly, high altitutude fighters with high altitude engines and extended wingspan fly better at altitude. Lower spanloading comes with less drag and 'grabs' the air better. The extreme case is the Ta 152H, which you seem to hate for some reason very much.

Now of course, the vast majority of Spitfires built were with normal ellipitic (or sometimes, clipped) winged MkVs and Mk IXs fitted with low-medium altitutude engines. 

Simply physics... It should, hence why Steinhoff notes 'at 28 000 feet'. Of course, if Steinhoff's unit would have been JG 1 for example, which had high altitude, GM-1 boosted, pressurized 109G-1s or G-3s, it would have been a different matter.

Now simply to put, if you want to show how much of a crap the Bf 109G was, maybe you should try better than quoting selected quotes taken out of context from revisionist fanboy sites.


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## pbfoot (May 11, 2007)

The stance on the 109 under cart is wider by 6" or 12 cm then that of the Spit


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## lesofprimus (May 11, 2007)

> Quote:
> The Ta-152 turned quite well at high altitudes, but was extremely vulnerable to "regular" Allied fighters at lower altitudes ...
> 
> That is so very untrue, and just shows how little you really know on the subject !
> ...


This whole part of the discussion disturbs me.... Greg, u really need to educate urself alot more on the 152.... Ur embarassing urself..... Ur getting into an argument with some heavy hitters who've made more than 100 posts like urself....

Oh, and BTW, what was the P-51H and the P-47M kill ratios again???


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## Rapecq (May 11, 2007)

Hi

GregP wrote:


> As for the much-vaunted Ta-152, they only made 67 of them in the entire war! How big an effect could they possibly have? The first production prototype was tested in January 1943, but they didn't make any production planes until 21 November 1944, and only completed ten Ta-152H-1's by the war's end. The rest were a mixed bag of prototypes.
> 
> Yeah ... BIG effect in the war. Tell me about it. They're gonna' shoot down the Allied Air Forces with 67 fighters, many of which were unserviceable on any given day?
> 
> I don't follow that. These same guys who vaunt the Ta-152 as the "best of the best" refuse to consider the P-51H or the P-47M. We built more than 67 of BOTH before the war ended ...



My little observation: in this topic we are not trying to assess the German industry situation in 1944-45 and we're not trying to show how great influence on the war P-51 or Bf 109 had.In my opinion making an assessment (of fighter's characteristics) based on the number of produced is a bit unjust and unfair. 

Regards


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## DerAdlerIstGelandet (May 11, 2007)

GregP said:


> Sorry, but even German references state the Bf 109's characteristics at above 400 mph. Maybe you are reading Luft46, where they think EVERYTHING German was the best in the world and still, to this day, cannot understand reality? Sorry Kurfurst, your arguments just don't hold up to the facts as I read them but you are, of course, certainly entitled to your opinions as am I mine.



I would never use Luft46 as my main source and I dont think that the Germans built everything superior and never have, but I also dont think the Allies did the same either as a lot of people seem to do...



GregP said:


> As for the much-vaunted Ta-152, they only made 67 of them in the entire war! How big an effect could they possibly have?



Who cares what kind of effect it had. We are not talking about the effect of the war. We are talking about individual planes. The P 80 had not effect on the war but everyone seems to want to throw it around...

See my point.



GregP said:


> Yeah ... BIG effect in the war. Tell me about it. They're gonna' shoot down the Allied Air Forces with 67 fighters, many of which were unserviceable on any given day?
> 
> I don't follow that. These same guys who vaunt the Ta-152 as the "best of the best" refuse to consider the P-51H or the P-47M. We built more than 67 of BOTH before the war ended ...



Again read my post above. Who cares about effect on the war when comparing aircraft performance and capabilities. 

Oh and using your logic, we can automatically throw out the P-51H. It saw absolutely no combat in WW2. *Yeah ... BIG effect in the war.*



GregP said:


> The Me 109 COULD NOT have been a bad fighter. It was the most-produced fighter ever in history and that says a lot about it. But it DID have its bad pionts and that's where I firmly disagree with the diehard Messerschmitt fans. They all seem, like you, to think it had no faults, and that just isn't so. It DID have faults, as did ALL fighters produced by all manufactureres of all sides and nationalities. There was NO fighter that was best at everything.



Im a Bf 109 freak, it is my favorite plane but I dont think it was without faults...


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## Juha (May 11, 2007)

“German tests done on a well worn 109F in late 1944 (it should be considered the 109G had more rigid, reinforced wings, so wing flexing would be less noticable) show that the aircraft could have a maximum stick deflection with 30 kg stick force, and still possess have it's peak ca.80-90 degrees/sec roll rate at ca 625 km/h TAS at 3 km altitude.”

Kurfürst, 
funny how different people draw different conclusion from same graph and text. A Finnish expert, Jukka Raunio, wrote in a article that the tests showed that the max rollrate of the 109F used in the tests was achieved at a bit over 500km/h (TAS), when the full roll took 4½ sec. And my interpretation from the report is the same, ie. max roll rate was achieved in the tests at c. 525-530km/h (TAS). I admit that I had time only look the pages 10-13 of the report. IMHO the 30 kg curve is calculated, not flown.


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## GregP (May 11, 2007)

Well, I see at least some of us are willing to discuss different opinions. The others have little tolerance for another opinion; shows who they are inside. All this "put down" of other opinions does you all an injustice. Be adults, make your points and leave out the insults, how about it?

I've been studying WWII aviation since about 1960 and, if you'll give me credit for even modest intelligence, I cannot have gotten it ALL wrong in that time, especially since one of the three higest-scoring aces in the history of the world, and a German ace at that, agrees with me. That would be Gunther Rall.

You're probably ruight, what does HE know? He's only in the top 3 aces of all time ... I talked with him at an art show for about 30 minutes and he verified the handling of the Bf 109s and Fws HE flew in combat, down to the high-speed and low-speed manners. Sorry guys, he was there and I believe HIM. There is nothing saying YOU have to do so, please believe as you choose.

Maybe you guys have flown all the WWII flight simulators, I don't know. What I DO know is that some of what you say has basis in what I have read and heard over many years, but some doesn't ... you are entitled to believe as you choose. Please do so in good health.

And sorry guys, the sixty seven Ta 152s didn't make a scratch in the Allied war effort, nor did the Me 262s. They never got more than a bit under 300 Me 262's into combat and they didn't do much to stem the tide of bombs coming from thousands of B-17s escorted by thousands of good old P-51s.

Both of these planes were really small bands of prototypes that were forced into service early due to the fact that Germany was losing the war. The brunt of the war was fought b y the Bf / Me 109 along side the radial-engined Fw 190 series with a small bit of help from the Fw 190Ds ... the only liquid-cooled 190s that made into into anything like service. The best known is perhaps the Fw 190 D-9 and enough were built that it can be considered as a combat aircraft in the classic sense. That is, enough were built to make it seem like an actual production machine.

You guys will probably disagree (shock!), but I think the Fw 190D-9 was the best fighter the Germans fielded in anything like production quantities. In the D-9 mark, it was everything a P-51D or late-model Spirfire could handle and possibly a bit more. It was enough better that it MAY be the case that the outcome of combat was more dependent on the planes than the pilot.

If you disagree, please just say so and leave out the personal comments. You don't know me and I don't know you, so you don't know what you're talking about when you make personal comments.

You guys that make sweeping statements about the Ta 152s must have personal knowledge that no one else in the world sems to have. Not enough of them were built to really make it into combat (most never SAW combat or even FLIGHT due to lack of both pilots and fuel), and the pilot reports that everyone quotes are from Kurt Tank, a designer ... NOT a combat pilot. What in the heck would HE know about combat? He never did it.

Pulling away once from some Mustangs that had no idea they were fighting anything special doesn't say anything about the capabilities of either the Mustangs or the Ta 152. It says that a scared aircraft designer, using war emergency power, was able to outrun some cruising Mustangs who didn't bother to chase a single Focke-Wulf late in the war. And that's ALL it says. Let's remember they were over Germany and were a long way from home. Might have been very different if they were over Allied territory, were mad as hell that day, or happened to be in a better tactical position at the start of the engagement.

Whatever you claim, one or two, or even several outcomes don't define the performance of a fighter type. The aggregate record does. And Spitfires, Mustangs, Yak-3s and La-5/7s shot down a LOT of Focke-Wulf 190s anf Bf / Me 109s. And that is a fact you can't discount, even in a fantasy world.

If we had not invented jets, the question of the best piston fighter might well ahve been answered, and it could have been any one of MANY planes. In REAL fact, most of the combatants chose to give up on piston fighter design and development and concentrate on the development of jets. 

So, we are left to discuss the relative merits of the piston planes that existed. Probably none of us in here have flown them in anger. I have some front-seat T-6 time and some back-seat TF-51 time, and I can't say how they fly at the edge of the envelope since we carefully avoided the edge of the envelope on my flights. Weren't MY planes and, if they were, I'd STILL avoid the edges of the envelope unless a rich uncle would pay for the engine rebuild.

So, I wonder how you can all be so sure which one is "best" or what it characteristics were at the limit, especially since the best pilots I know, pilots who fly WWII aircraft EVERY WEEKEKND, don't know. They take the word of the pilot's manuasl. And those manual tell what the designers found in flight tests.

I'm outta' here and into a place where the forum members DISCUSS WWII aviation like they were actually interested in various viewpoints. If you happen to find that forum, please join the discussion and leave the antics here, where the real joke resides. HE has over 1900 posts, but can't discuss them unles you agree with everything he has to say ... and THAT just isn't discussion.


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## lesofprimus (May 11, 2007)

> That would be Gunther Rall.
> 
> You're probably ruight, what does HE know? He's only in the top 3 aces of all time ... I talked with him at an art show for about 30 minutes and he verified the handling of the Bf 109s and Fws HE flew in combat, down to the high-speed and low-speed manners. Sorry guys, he was there and I believe HIM. There is nothing saying YOU have to do so, please believe as you choose.


Ive met Mr. Rall on several occasions and discussed many different things.... I can confirm the stick force issue, but ur making it bigger than it was...



> and the pilot reports that everyone quotes are from Kurt Tank, a designer ... NOT a combat pilot. What in the heck would HE know about combat? He never did it.


Ummm, I think Mr Reschke saw alittle combat back then didnt he???



> I'm outta' here


See ya, dont let the door kick u in the ass on the way out... U gotta have thick skin here... U aint the first to cry like this on these very pages, and u wont be the last....



> please join the discussion and leave the antics here, where the real joke resides.


And that snyde ass little comment gets u


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## Soundbreaker Welch? (May 11, 2007)

He meant by "real joke resides" one of the members or just the forum? 

Not trying to get myself banned here or anyone else but GregP was called a joke too in an earlier post.

Anyway, put it behind, doesn't seem like he wanted to come back, what now? 

I think it's generally seen by everyone, the P-51 was a bit of a turkey at low altitude manuvering. I heard high speed helped the P-51's roll rate rather than hindered it? 

By the way this thread went, it's interesting how the characteristics of the Bf 109 are needed to see the characteristics of the P-51, but I guess thats the only way to tell. The manuverabilty of the P-51 depends on how well it fared in combat and how it's opponents could best it, and not just testing by the mother country.

Sorry, off topic but was the tightest turner the Ta-152 or the Spitfire Mk VIII? What about the Spitfire XIV?


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## Kurfürst (May 12, 2007)

Juha said:


> “German tests done on a well worn 109F in late 1944 (it should be considered the 109G had more rigid, reinforced wings, so wing flexing would be less noticable) show that the aircraft could have a maximum stick deflection with 30 kg stick force, and still possess have it's peak ca.80-90 degrees/sec roll rate at ca 625 km/h TAS at 3 km altitude.”
> 
> Kurfürst,
> funny how different people draw different conclusion from same graph and text. A Finnish expert, Jukka Raunio, wrote in a article that the tests showed that the max rollrate of the 109F used in the tests was achieved at a bit over 500km/h (TAS), when the full roll took 4½ sec. And my interpretation from the report is the same, ie. max roll rate was achieved in the tests at c. 525-530km/h (TAS). I admit that I had time only look the pages 10-13 of the report. IMHO the 30 kg curve is calculated, not flown.



If you read the report, it shows indeed the roll rate tops out at ca 500 km/h, then it remains about the same up to about 610 (full deflection is still achieved), then goes down as on other roll graphs which shows full deflection is not longer possible.

Indeed the 30 kg curve is 'calculated' - like all graphs in the report, flights were done at various deflections, then the results were extrapolated for various stickforces from the flight test results. This was done because the testbed aircraft was destroyed by enemy action before the tests were concluded.

Bottomline, that DVL report was about measuring theoretical behaviour of aircraft structure (wing elastasy effect on roll rate), not determining the roll rate of the bf 109. Moreover, it can be safely presumed the 109F they used for tests, produced sometimes in 1941, was probably well worn out by the tests were made with it, in late 1944.

In any case, the roll rate doesn't seem to be a problem at the speeds the aircraft can reach in level flight at those altitudes (3 km), it starts to decrease at speeds which can be only achieved in dive, and it is fairly reasonable up the dive speed limits of the aircraft at that altitude.


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## Soren (May 12, 2007)

Soundbreaker Welch? said:


> Not trying to get myself banned here or anyone else but GregP was called a joke too in an earlier post.



Yes he was and with good reason. 

Read his last post, there are so many things he's got no clue about. He starts to refer to the incident where Tank out-ran some Mustangs as if that is our evidence that the Ta-152H was a much better a/c - we never even mentioned it ! Why does he do this ? cause he doesn't even know about the achievements of the Ta-152H in combat and has never read about the plane. 



> Anyway, put it behind, doesn't seem like he wanted to come back, what now?



Agreed.



> I think it's generally seen by everyone, the P-51 was a bit of a turkey at low altitude manuvering. I heard high speed helped the P-51's roll rate rather than hindered it?



That is correct, at high speed the P-51 felt at home - unless you went absolutely ballistic ofcourse.



> By the way this thread went, it's interesting how the characteristics of the Bf 109 are needed to see the characteristics of the P-51, but I guess thats the only way to tell. The manuverabilty of the P-51 depends on how well it fared in combat and how it's opponents could best it, and not just testing by the mother country.





> Sorry, off topic but was the tightest turner the Ta-152 or the Spitfire Mk VIII? What about the Spitfire XIV?



Tough question as they're so close. 

The Ta-152H was probably as good or better than the Spitfire Mk.XIV in turns, but the Mk.VIII is better.


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## lesofprimus (May 12, 2007)

Sorry Welch, but he was slamming the whole board, not just a single poster... We all kinda came down hard on him with his lack of knowledge etc etc, but dammit, this is a tough place....

And Welchy, u'd have to go pretty far for me to ban u, as I think u have something to add to this place... Noobs are easier to deal with....


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## lesofprimus (May 12, 2007)

Chinganook coming back as the ass hole he always was....


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## Brain32 (May 12, 2007)

I would just like to add a few things, first about that turn-rate chart, it's a nice piece of info, but I found some contradiction looking at separate ADFU trials. For example look at this, MustangIII vs unknown FW190A:


> 42. Turning circle
> Again there is not much to choose. The Mustang is slightly better. When evading an enemy aircraft with a steep turn, a pilot will always out-turn the attacking aircraft initially because of the difference in speeds. It is therefore still a worthwhile maneuver with the Mustang III when attacked


Maybe it's just me but words like "not much to choose" or "slightly better", especially when used against a captured airplane in unknown condition don't sound too superiour do they?

As for combat reports, they are as all pilot stories of anegdotal value only, the guy that survived the fight had to out-something the guy that did not.
Note that I'm not saying that P51 was POS, far from it, but it wasn't a wonder weapon either believe it or not 8)


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## lesofprimus (May 12, 2007)

> Note that I'm not saying that P51 was POS, far from it, but it wasn't a wonder weapon either believe it or not


And about 80% of all WWII aviation enthusiasts feel the same way....


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## J. Fenimore Cooper (May 12, 2007)

I am a dork...

I have no life and therefor act like a little child that does not get there way.


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## DerAdlerIstGelandet (May 12, 2007)

Idiot...


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## Juha (May 12, 2007)

Hello Kurfürst
Now Raunio reads the test so that at 600km/h (TAS) full roll took 7 sec. And looking page 12, Abb. 5, even 9 deg. line transformed from solid (gemessen/measured ) to dashed (extrapoliert) at little over 500km/h, and I’m not sure if the speed figure is compression corrected.

Now it’s true that the tests didn’t study roll rate itself and that 109G’s wing was a bit stiffer, so we cannot read too much from the test. And of course a more muscular pilot might have been able to use a bit more force to turn the stick but still IMHO the tests indicated problems in Bf 109’s ability at high speed roll.

Juha


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## Hop (May 12, 2007)

The 109 roll rate stuff is discussed Aces High BB - DVL data on Bf 109 roll rates

On page 3 someone has posted the NACA 868 roll rate graph with the Bf 109 data overlayed. What's interesting is that at 400 mph and 50 lbs stick force, the 109 has a lower roll rate than any of the other aircraft listed, worse even than the Zero.



> Tough question as they're so close.



What do you base this on?


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## Soren (May 12, 2007)

Hop said:


> What do you base this on?




Some of the very basic and some of the complex aerodynamics on this earth - and I will be happy to demonstrate this for you. 

Now what do you base your question on Hop ? curiosity or disbelief ?


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## Soren (May 12, 2007)

Brain32 said:


> I would just like to add a few things, first about that turn-rate chart, it's a nice piece of info, but I found some contradiction looking at separate ADFU trials. For example look at this, MustangIII vs unknown FW190A:
> 
> Maybe it's just me but words like "not much to choose" or "slightly better", especially when used against a captured airplane in unknown condition don't sound too superiour do they?
> 
> ...



Yes Brain and the Fw-190 in question is infact a G-2 fighter-bomber. 

Here's a pictrure of the a/c in question:


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## Soundbreaker Welch? (May 12, 2007)

> And Welchy, u'd have to go pretty far for me to ban u, as I think u have something to add to this place



Well, Thanks les. Yes, I do add polls to the forum!  


Here's a soviet test video of the 190, but it's all in Russian so I can't understand the commentary. I do think the music sounds rather happy, considering this is an enemy plane the Soviets don't have! 


_View: https://www.youtube.com/watch?v=qayREUJe65w_


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## Hop (May 12, 2007)

Disbelief. I'd like to see the maths that suggest the TA 152 will out turn a Spitfire XIV, except possibly over a very narrow altitude range, or at extreme altitude. I haven't actually checked the figures myself, so anything's possible, I just find the idea unlikely.


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## Kurfürst (May 12, 2007)

Hop said:


> On page 3 someone has posted the NACA 868 roll rate graph with the Bf 109 data overlayed. What's interesting is that at 400 mph and 50 lbs stick force, the 109 has a lower roll rate than any of the other aircraft listed, worse even than the Zero.



Facts vs. Hop, as usual...





Errate : the '30 lbs' blue line label is for 50 lbs for the 109.

It should be noted that the Spitfire roll rate figures come from RAE, nder totally unknown circumstances. They contradict all other sources regarding both roll rate and characteristics. Ie. AVIA 6/10126 :






NACA trials showed the following for the Spitfire :
_

"Measurements of the flying qualities of a Supermarine Sptitife VA airplane." NACA Advanced Confidental Report, by William H. Phillips and Joseph R. Vensel. 

The tests were conducted at Langley field, Va., during the period from December 30, 1941 to January 29, 1942. Sixteen flights and apprx. 18 hours flying time were required to complete the tests. 

[...] 

Desription of the the Supermarine Spitfire airplane 

Name and Type : Supermarine Spitfire VA (Air Mininstry No. W3119). 
Engine : R-R Merlin XLV 
Weight, empty : 4960 lbs 
Normal gross weight : 6237 lbs 
Weight as flown for tests : 6184 lbs 

Ailerons (metal-covered) 
Lenght (each) : 6 feet, 10 1/2 inches 
Area (total area, each) : 9.45 sq. feet 
Balance area (each) : 2.45 square feet 

[...] 

A stick force of 2 lbs to the right and 3 lbs to the left was required to overcome aileron friction. 

[...] 

Lateral Stability and Control 

Aileron-control characteristics : The effectiveness of the ailerons of the Supermarine Spitfire airplane was determined by recording the rolling velocity produced by abrubtly deflecting the ailerons at various speeds. The aileron angles and stick forces were measured. It should be noted that the airplane tested was equipeed with metal covered ailerons. 

[...] 

The ailerons were sufficiently effective at low speeds, and were relatively light at small deflections in high speed flight. The forces required to obtain high rolling velocities in high-speed flight were considered excessive. 
With a stick force of 30 lbs, full deflection of the ailerons could be obtained at speeds lower than 110 miles per hour. A value of pb/2V of 0.09 radian in left rolls and 0.08 radian in right rolls were obtained with full deflection. 

*Rolling velocity (at 6000 ft altitude) of about 59 degrees per second could be obtained with 30 lbs stick force at 230 miles per hour indicated speed. *

The ailerons were relatively light for small deflections, but the slope of the curve of stick force against deflection increased progressively with deflection, so that about five times as much force was required to fully deflect the ailerons as was needed to reach one-half of the maximum travel. The effectiveness of the ailerons increased almost linearly with deflection all the way up to maximum position. The value of pb/2V obtained for a given ailerons deflection was nearly the same in speeds and conditions tested. It may be concluded, therefore, that there was very little reduction in aileron effectiveness either by separation of flow near minimum speeds or by wing twist at high speed. 

Fig 27 shows the aileron deflection, stick force, and helix angle obtained in a series of roll at various speeds intended to represent the maximum rolling velocity that could be readily obtained. 

*The pilot was able to exert a maximum of about 40 lbs on the stick. With this force, full deflection could be attained only up to about 130 miles per hour. Beyond this speed, the rapid increase in stick force near maximum deflection prevented full motion of the control stick. Only one-half of the available deflection was reached with a 40 lbs stick force at 300 miles per hour,* with the result that the pb/2V obtainable at this speed was reduced to 0.04 radian, or one-half that reached at low speeds. 
_


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## Soren (May 12, 2007)

Hop said:


> Disbelief.



I thought so.



> I'd like to see the maths that suggest the TA 152 will out turn a Spitfire XIV, except possibly over a very narrow altitude range, or at extreme altitude. I haven't actually checked the figures myself, so anything's possible, I just find the idea unlikely.



Sure, lets say the matchup is at SL, I'll even provide the basic figures.

We'll assume a CLmax of around 1.45 for the Ta-152 as CLmax is going to increase slightly with AR. The Spitfire's CLmax is going to be 1.35 - Any objections ?. As to 'e' (Oswald efficiency factor), well I'm guessing the Spitfire's to be abit higher despite the aerodynamic twist of the wing.

*The basic figures*

Ta-152H CLmax: 1.45 (This is a low educated guess, it might be higher)
Ta-152H 'e': 0.8
Spitfire Mk.XIV CLmax: 1.35
Spitfire Mk.XIV 'e': 0.83

Cd0 is unknown for the Ta-152H so therefore total drag will be represented by the Cdi. (And don't worry, the Cd0 isn't a decisive figure)

Height: Sea Level
Temperature: 15 C
Pressure: 101325 Pascals
Atmosphere: 1.164 Kg/m^3
Speed of sound: 349 m/s

Speed is going to be 600 km/h, the absolute higest speed for both a/c at SL.

*Ta-152H-1 Aerodynamics at SL*

Lift: 

L = 1.45*23.3*.5*1.164*600^2 = 7078633.2

Drag:

Cdi = (1.45^2)/(pi*8.94*.80) = 0.0935747393
Cd0 = -Unknown-

D = 0.0935747393*23.3*.5*1.164*600^2 = 456814.66

L/D ratio = 15.49
L/W ratio = 1487

*Spitfire Mk.XIV Aerodynamics at SL*

Lift:

L = 1.35*22.48*.5*1.164*600^2 = 6358512.96

Drag:

Cdi = (1.35^2)/(pi*5.61*.83) = 0.124588142
Cd0 = -Not included-

D = 0.124588142*22.48*.5*1.164*600^2 = 586811.345

L/D ratio = 10.83
L/W ratio = 1651
_______________________________

Ta-152 H-1 L/D = 15.49
Spitfire Mk.XIV L/D = 10.83

Ta-152 H-1 L/W = 1487
Spitfire Mk.XIV L/W = 1651

Thats an extra 43% of lift pr. amount of drag for the Ta-152 H-1 and an extra 11% of lift pr. weight unit for the Spitfire XIV. This indicates that the sustained turn rate of the Ta-152 H-1 is higher than the Spitfire MK.XIV's, while the Spitfire Mk.XIV's instanious turn rate is higher than the Ta-152 H-1's. 

And this is at high speed and at SL mind you - for the Spittie's sake lets not go higher


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## Soundbreaker Welch? (May 12, 2007)

Well, the big Griffon engine wasn't well liked anyway, except for high altitude flying, which was a good thing. Now Spitfire XVI had the same frame as the Spit XIV, excpet it was a low altitude Spitfire with a Merlin engine. I imagine it's turn rate was better than the Spitfire XIV.


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## Hop (May 13, 2007)

> What's interesting is that at 400 mph and 50 lbs stick force, the 109 has a lower roll rate than any of the other aircraft listed, worse even than the Zero.
> Facts vs. Hop, as usual...



Um, Kurfurst, you've reposted the chart that shows exactly what I said. Apart from the Spitfire at 30 lbs stick force that you've drawn in, that is.

NACA 868 shows roll rates at 50 lbs stick force for all aircraft apart from the Zero, where the force limits are unknown. The 50 lbs line for the 109 falls below all the other aircraft I can see.



> It should be noted that the Spitfire roll rate figures come from RAE, nder totally unknown circumstances.



No, as we have been over ad nauseum, they are tested results for the Spitfire V, given along with the Mustang and Typhoon figures by the RAE as a comparison with the Fw 190.



> NACA trials showed the following for the Spitfire :



Four problems with the Naca roll figures for the Spitfire.

First, it was a very worn aircraft. Robert Standford Tuck:


> It happened that Wright Field had the only Spitfire in America-a Mark V. Unfortunately almost every pilot in the Air Corps had had a go on her and like a car that had too many drivers, she was the worse for wear...'She was very tired, very sloppy-she'd had the guts caned out of her all right.



Second, it was a Spitfire Va. That's the last of the machine gun armed variants, and so didn't have the wing strengthening applied to the cannon armed aircraft. Va's also came from the factory with fabric ailerons, so we don't even know if the "metal ailerons" fitted were the standard production items.

Third, Naca published the report containing the 868 graph post war. They chose to use the RAE's figures for the Spitfire, rather than their own.

Fourth, the RAE tested the roll rates of the Spitfire against other aircraft. We'll leave out the fact they said it rolled much better than the 109s, because you will just come out with excuses that they couldn't fly the 109 properly. But they also tested against a range of American aircraft, which they used extensively, and with manufacturers support.

Vs P-47C:


> The good aileron control gives the P-47 an excellent rate of roll even at high speeds, and during mock combats it was considered to roll as well as, if not better than the Spitfire at about 30,000 feet. At lower altitudes there is nothing to choose between them.



Vs P-51B:


> Although the ailerons feel light, the Mustang III cannot roll as quickly as the Spitfire IX at normal speeds.



Edit: Soren, I'll reply later in the day. I need to wake up to do maths


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## Brain32 (May 13, 2007)

Interesting thing is Hop, that whenever we discuss a Spitfire testing, if the results are bad, heck, even if the paint job from artistic POV is being discussed and criticized you dismiss those results by whatever means possible, but in the same time tests of crash-landed, shot down, 190's and 109's maintained and flown by untrained personel, you take as apsolute truth and perfect example of a service plane. Now that's just funny  
Fortunetly this is not ubi forum , so I think people see that...


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## FLYBOYJ (May 13, 2007)

Hop said:


> Four problems with the Naca roll figures for the Spitfire.
> 
> First, it was a very worn aircraft. Robert Standford Tuck:
> 
> ...



Hop - I'd like to know where that came from....

Listen folks - when I hear pilots (even the greatest aces and test pilots) make statements that the aircraft is "worn out," I have to laugh. Many of these folks had little or no maintenance backgrounds and made these determinations sometimes by outward appearances and comparing one same aircraft to another. What wears an aircraft out?

1. High engine or propeller time - flying an aircraft that doesn't have high compression, leaky superchargers, or a propeller that will not hold pitch. Maybe there are other conditions (bad magnetos) worn internal engine components etc. that was causing the said engine not to meet advertised performance numbers. I doubt Wright Pat would of operated an aircraft with an engine not meeting "book performance."

2. Airframe - If the airframe has been pranged several times, beat up and if major repairs were done to the aircraft that probably knocked out the overall asymmetry of the aircraft. If an aircraft with high airframe time is properly maintained, properly rigged and never suffered any major damage, it should fly almost as good as one straight out of the factory. The only thing an aircraft in service tends to do is gain weight because of dirt finding it way into the airframe structure over time.

As many of us seen, in the back of each Pilot's notes or flight manual are performance numbers. If the aircraft meets those numbers that's the bench mark of performance. Now if there is something physically wrong with the airframe, as stated it's a whole different story and none of these expert pilots ever specifically state what the problem is. I call this a "pilot placebo."

My 2 cents....


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## Marcel (May 13, 2007)

I've read the same text as Hop mentioned in "Fly for your Life" by Larry Forrester and when I read it I was wondering the same thing as you Flyboy. I can only imagine that the cables would wear out, hence the slugginess, but then again, you probably know more about that than I do. Would be nice to have an explanation about this.


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## FLYBOYJ (May 13, 2007)

Marcel said:


> I've read the same text as Hop mentioned in "Fly for your Life" by Larry Forrester and when I read it I was wondering the same thing as you Flyboy. I can only imagine that the cables would wear out, hence the slugginess, but then again, you probably know more about that than I do. Would be nice to have an explanation about this.


Correct Marcel - even with control cables wearing out, they could be adjusted and eventually replaced - this is a common maintenance action. Don't get me wrong, I have the utmost respect for those who flew these aircraft during these tests but I think those who recorded pilot statements as a result of these test did not press for real explanations or were not technical enough to understand what the test pilot was talking about. In either case I take with a grain of salt when I hear someone say "the aircraft had a worn airframe" when discussing these types of comparisons...


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## Marcel (May 13, 2007)

Yeah, I would take the whole book with a grain of salt as it only seems te be written to tell everyone what a nice chap Tuck was. Not that I dispute he could have been a good fellow, but I rather read some more objective literature.


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## FLYBOYJ (May 13, 2007)

I guess the whole point here is "specific" things will cause an aircraft not to perform as advertised. In the case of the Spitfire Va used on the mentioned tests, its best to compare the actual aircraft's performance against what the manufacturer said the aircraft can do...

The moral of this story folks is unless the pilots say specifically what was wrong with an aircraft "that wasn't performing properly," or "was worn out," take the comment with a grain of salt..


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## Sgt. Pappy (May 13, 2007)

Soundbreaker Welch? said:


> Well, the big Griffon engine wasn't well liked anyway, except for high altitude flying, which was a good thing. Now Spitfire XVI had the same frame as the Spit XIV, excpet it was a low altitude Spitfire with a Merlin engine. I imagine it's turn rate was better than the Spitfire XIV.



The Spitfire XVI had the same frame as the Spitfire IX but with an American-built Packard-Merlin 266 which was practically identical in performance to the Merlin 66. This difference is the only diff that all 100% of Mk.XVI's had vs. the IX. The new variant number was applied as the two engines required different tooling. Some pilots viewed the XVI's as a bit of a 'Mk.IX reject' due to the engine failing a little more easily.

The Spitfire XIV had the same frame as the Spitfire VIII; a variant that had shorter ailerons than the Mk.IX along with extra fuel tankage in the leading edge of each inboard wing section and a strengthened airframe in addition to a retractable tailwheel. All in all, the empty Mk.VIII weighed some 182 lbs. heavier than the Mk.IX while the Mk.XIV weighed a whopping 830 lbs. heavier empty.

For the record, the wing twisting of the Spitfire (wash out effect) allowed for a more gentle/obvious stall which was good for novice pilots. The disadvantage of this feature was the roll rates at high speed. No matter what wing - regular tip or clipped, the washout badly degraded roll at high speed. Plus, it is said that no two aircraft perform exactly the same; even a dent, scratch or lodged pebble may affect performance. The best we can hope to do is get the general idea of the plane's performance and go from there.


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## AV8 (May 14, 2007)

New member here, where in hell did you get the graphs above?

Been looking for that stuff for a long time! Is it available for other aircraft?

I have been looking for just such a comparison, but, of course, the altitude makes all the difference. Superchargers and turbochargers made a huge difference in the performance of the various airframes. 

Example was the P-39. WITH the turbocharger it was world beater. Without the turbo, it was a world beater below 12 to 15 thousand feet, but was miserable above that altitide.

So the Soviets kicked ass with the P-39 while WE didn't use it much unless we HAD to.

So ... where are all these performance graphs located?

I have extensive files of air kills, conflicts, and pilot names, but all are by country and name. None are by what aircraft type the pilot was flying or what aircraft was killed. Seems almost like a conspiracy of disinformation ...

Anyone HAVE these data? If so, you are the savior of all WW2 aviation fans all over the world!

PLEASE post or send an email link!


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## Jabberwocky (May 14, 2007)

AV8 said:


> New member here, where in hell did you get the graphs above?
> 
> Been looking for that stuff for a long time! Is it available for other aircraft?
> 
> ...



All the NACA historical documents are available at the NASA archives:
NASA Technical Reports Server

Diasgree that the P-39 was a "worldbeater" with the turbosupercharger.

Fundamental problem is that, due to many reasons, the performance of the XP-39 couldn't really have been replicated on production machines (combined with the philisophy of the USAAF at the time didn't really favour high altitude interceptors).

The excellent 390 mph top speed and 5 minutes to 20,000 feet climb figures that the turbosupercharged XP-39 achieved in testing were for an unarmed, unpainted, polished prototype without any military equipment. 

The XP-39 that achieved them weighed just 3,995 lbs at empty (only 200lbs heavier than an empty A6M Zero and more than 1,400lbs lighter than P-40 protoypes). If you add military equipment, like self sealing fuel tanks, military radios, antenna, armour, guns, gunsights, gun heaters, ammunition, IFF and all the other stuff necessary to make the plane a workable fighter, performance is going to take a nose dive. 

Aerodynamics get messed up by airframe projections (gunports, antenna, ejector chutes, ect) and camoflage paint. The RAF found they lost 7 mph in top speed at sea-level from the its Allison engined P-51s after painting them. 

Just to give an idea of how much weight creep there would be; The empty weight of the YP-39 was 5,040 lbs, up just over a 1,000 lbs from the 3,995 lbs of the XP-39. That's a weight gain of just over 25% on the empty weight AFTER stripping out the turbosupercharger.

Loaded weight shot up from 5,550 lbs for the unarmed XP-39 prototype to 7,070 lbs for the armed YP-39, and it was still without internal or cockpit armour and had no self sealing fuel tanks. When these, and more guns and ammunition were added, combat weight climbed by another 500lbs.

So, a fully loaded, combat capable P-39D circa September 1941, weighed around 7,650 lbs combat loaded, almost a full 2,100lb heavier than its turbosupercharged XP-39 ancestor. That is a weight gain of about 38%. Its empty weight was 1,400lbs higher than that of the XP-39 prototype. That increase would markedly effect handling, speed and climb performance.

Would the P-39 have been better a better fighter in the ETO and Pacific if the USAAF had left it alone? Yes, but probably not by much. It would of been marginally slower and less manouverable down low, but progressively faster above 15,000 feet. Its problems with CoG and cannon reliability would of still existed.

To turn the P-39 into a combat capable fighter it needed all that equipment. So, the weight creep, that was always going to happen, meant that the performace exhibited by the prototype wouldn't of been achievable in real life until there was a serious jump in power in the military models.


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## Jabberwocky (May 14, 2007)

Soren said:


> I thought so.
> 
> Sure, lets say the matchup is at SL, I'll even provide the basic figures.
> 
> We'll assume a CLmax of around 1.45 for the Ta-152 as CLmax is going to increase slightly with AR. The Spitfire's CLmax is going to be 1.35 - Any objections ?.



Raises hand  

NACA L-353 reports Spitfire CL max at cruise condition (2650 rpm, 3 3/4 lbs boost), gear up, flap up, ports open, as 1.68. 

What does this do to the calculations?


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## Soren (May 14, 2007)

Jabberwocky said:


> Raises hand
> 
> NACA L-353 reports Spitfire CL max at cruise condition (2650 rpm, 3 3/4 lbs boost), gear up, flap up, ports open, as 1.68.
> 
> What does this do to the calculations?



Clmax figures with the engine running isn't valid, what we need and what we're using is free float figures. With the engine running CLmax is going to be raised quite significantly, more so by the a/c which provides the most thrust which would be the Ta-152.


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## Sgt. Pappy (May 14, 2007)

Random question. Wondering if the CLmax of the F4U-1A/D Corsair in different flap settings was affected by the inverted gull wing.


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## Hop (May 15, 2007)

> Hop - I'd like to know where that came from....



Fly for your life, as already quoted.



> Listen folks - when I hear pilots (even the greatest aces and test pilots) make statements that the aircraft is "worn out," I have to laugh. Many of these folks had little or no maintenance backgrounds and made these determinations sometimes by outward appearances and comparing one same aircraft to another.



Fair enough. However, I am not an experienced mechanic, yet give me a worn out car of the same model as the one I currently drive, and I will be able to tell if it's worn out. Sloppy steering, sluggish acceleration, worn shocks, poor brakes, all should be apparent to a driver with experience of that model.

Tuck had a lot of hours in Spitfires, and so should have known if the Spit was worn out or not.



> What wears an aircraft out?



Use, I'd have thought. I can well imagine that a Spitfire in the US in the summer of 1941 would have been a popular aircraft, with USAAF pilots queueing up to have a go. The Spitfire was after all the star allied fighter at the time.



> As many of us seen, in the back of each Pilot's notes or flight manual are performance numbers. If the aircraft meets those numbers that's the bench mark of performance.



Yes, but that says nothing about handling. A well maintained engine has no effect on roll rate, which is determined by the correct rigging of the ailerons. For that you have to know the droop, the tension in the cables etc. Was the Spitfire being serviced by squadron mechanics who had experience of such things? Did it even have standard ailerons for them to have experience on?

This particular Spit was shipped to the US in mid May 1941. Sholto Douglass (head of Fighter Command) complained in June 1941 that "only now are Spitfires with metal ailerons being delivered from the factory".



> Don't get me wrong, I have the utmost respect for those who flew these aircraft during these tests but I think those who recorded pilot statements as a result of these test did not press for real explanations or were not technical enough to understand what the test pilot was talking about



Tuck wasn't actually involved in the tests, he left the US some months before they began. He was simply giving his opinion of an aircraft he came across.



> Interesting thing is Hop, that whenever we discuss a Spitfire testing, if the results are bad, heck, even if the paint job from artistic POV is being discussed and criticized you dismiss those results by whatever means possible, but in the same time tests of crash-landed, shot down, 190's and 109's maintained and flown by untrained personel, you take as apsolute truth and perfect example of a service plane. Now that's just funny



It would be strange if it was true. It's fiction, though.

I very rarely present enemy testing of aircraft as "truth", for those reasons. If you look I did not quote German aircraft roll rates obtained by the RAE, for that very reason. Perhaps you could dig up some examples of me holding up RAE test figures for captured German aircraft as gospel truth?



> So ... where are all these performance graphs located?


Try WWII Aircraft Performance


----------



## Hop (May 15, 2007)

> We'll assume a CLmax of around 1.45 for the Ta-152 as CLmax is going to increase slightly with AR. The Spitfire's CLmax is going to be 1.35 - Any objections ?



Yes. The RAE's response to NACA over the faults in their tests of an early Spitfire V complained of the inaccurate method they'd used to record stall speed, and gave the measured CL for the Spitfire of 1.36 on the glide and 1.89 at full throttle.



> Clmax figures with the engine running isn't valid, what we need and what we're using is free float figures. With the engine running CLmax is going to be raised quite significantly



Aircraft rarely fight with their engines off. Glide performance is not really relevant to combat.



> more so by the a/c which provides the most thrust which would be the Ta-152.



What on earth makes you think the Ta 152 is going to have more thrust?

Peak power output on the Jumo 213E was 2050 ps, about 2020 hp.

Peak power output on the Griffon 65 was 2200 hp.

And that's rammed power for the Griffon, static for the Jumo. Rammed power increases critical altitude, but decreases the peak power, so the difference is more than 200 hp more for the Griffon.



> Speed is going to be 600 km/h, the absolute higest speed for both a/c at SL.



You're measuring turn rates at maximum speed? Sustained turn rate at maximum speed is by definition zero, and any WW2 prop fighter is not going to be able to spend long at 600 km/h if it's turning, no matter how much energy it carries into the manoeuvre.



> As to 'e' (Oswald efficiency factor), well I'm guessing the Spitfire's to be abit higher despite the aerodynamic twist of the wing.



I'd guess a bit more difference in E numbers, but I'll go with your figure just to illustrate the point.

Assume a fairly moderate turn, lift = 2 x weight, speed = 450 km/h

Lift (N) = CL * area (sq m) * .5 * pressure (kg/cubic m) * velocity (m/s) squared

Spitfire: 74832 = CL*22.48*.5*1.225*125^2
CL = 0.348

Ta 152: (I don't know the weight, but I'm using 4,750 kg, correct me if it's wrong)

93100 = CL * 23.3 * .5 * 1.225 * 125^2
CL = 0.418

So at these CLs, both aircraft will be turning at the same rate. Plugging those figures into the drag equation:

Spit: CDi = (0.348^2) / (3.142*5.61*.83) = 0.008
Ta 152: CDi = (0.418^2) / (3.142*8.94*.8 ) = 0.008

The Ta has a very slightly lower CDi, but you have to go to another decimal place to see the difference. Considering the Oswald ratios are guesswork, there's not really much point.

However, that's just the coefficient of induced drag, not actual induced drag. Induced drag itself is found by multiplying by the wing area, which is a bit greater on the Ta 152.

So the Ta 152 has a bit more induced drag in an identical turn. And less power to boot.

Taking the speeds down to tight turn fighting territory, 250 km/h:

Spitfire: 74832 = CL*22.48*.5*1.225*69^2
CL = 1.14

Ta 152: 93100 = CL * 23.3 * .5 * 1.225 * 69^2
CL = 1.37

Spit: CDi = (1.14^2) / (3.142*5.61*.83) = 0.089
Ta 152: CDi = (1.37^2) / (3.142*8.94*.8 ) = 0.084

Multiplying by wing area: 
Spit = 22.48 * 0.089 = 2.0
Ta 152 = 23.3 * 0.084 = 1.95

The Ta 152 has a 2% advantage in induced drag, but 10% or so disadvantage in power, which more than offsets the induced drag advantage.

Of course, we really need to know the parasitic drag figures as well for a more accurate result.

And this is against the Spitfire XIV. The real late war turner is the Spitfire IX with 25 lbs boost, which gave as much power as the Ta 152 at low altitude, but in a much, much lighter aircraft.

The Ta 152 was a fantastic turner compared to other 190s, but not on par with the Spitfire.


----------



## FLYBOYJ (May 15, 2007)

Hop said:


> Fly for your life, as already quoted.
> 
> Fair enough. However, I am not an experienced mechanic, yet give me a worn out car of the same model as the one I currently drive, and I will be able to tell if it's worn out. Sloppy steering, sluggish acceleration, worn shocks, poor brakes, all should be apparent to a driver with experience of that model.
> 
> Tuck had a lot of hours in Spitfires, and so should have known if the Spit was worn out or not.



Everything described has to do with maintenance - if the item is well maintained there should be no difference. A pilot will not necessarily know the difference be it Stanford Tuck or Chuck Yeager. Even in WW2 there was a methodology in aircraft maintenance that should of kept the aircraft maintained to established parameters.



Hop said:


> Yes, but that says nothing about handling. A well maintained engine has no effect on roll rate, which is determined by the correct rigging of the ailerons. For that you have to know the droop, the tension in the cables etc. Was the Spitfire being serviced by squadron mechanics who had experience of such things? Did it even have standard ailerons for them to have experience on?



I was using the engine as an example. 

Normal maintenance checks on most aircraft almost since the beginning of time includes cables tensions and control surface rigging (deflections). These items are routinely inspected during routine maintenance at timed intervals.


----------



## Hop (May 15, 2007)

> Everything described has to do with maintenance - if the item is well maintained there should be no difference.



Certainly. But if it was well maintained, why would Tuck describe it as "very tired, very sloppy"?



> Even in WW2 there was a methodology in aircraft maintenance that should of kept the aircraft maintained to established parameters.



Everything I have read about the rigging of Frise ailerons is that it was a tricky business, and difficult to get right. I wonder just what support there was for the Spitfire in the US,


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## FLYBOYJ (May 15, 2007)

Hop said:


> Certainly. But if it was well maintained, why would Tuck describe it as "very tired, very sloppy"?


If he was here I would ask him. I've seen high time pilots complain about a perfectly good aircraft. Everything was in limits, all rigging and systems were checked and for some reason they thought there was something wrong with it and appearances always has a lot to do with it. Not being there one could only speculate - That's why you have probably seen that web page about airline pilot writing up components and the mechanics coming back with some smart @ssed remark. (#4 engine seems to be running rough - replaced running shoes)

When I read these reports about a pilot making a comment - "the aircraft flew sloppy," or "the engine was running rough," unless they could come up with some quantified reasoning behind their claim, I take it with a grain of salt....


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## Soren (May 16, 2007)

Hop,

You've screwed up your calculations big time. And besides it is CLmax you want to be looking at, not CL in straight flight. - Unless you're under the impression that turning happens at low AoA ?? 

And as to thrust, well sorry but you can leave HP out of this, its actual thrust we're talking about here and the Ta-152H's new prop provided over 300 kg more thrust than the FW-190A's and with 50 less PS.

And as to the Oswald efficiency factor, what in the wolrd makes you think that the Spit's has a figure which is higher by more than 0.03 ???! 

Oh and about why you only use free float figures, simple, CL changes are variable with thrust and how big a part of the wing it covers - using free float figures allows us to figure out the effectiveness of the body itself.

Anyway lets do the calculations properly - and lets even try with a lower speed figure this time to show you that it doesn't make any appriciable difference. This time I'll also do speed figures in m/s like you, but again not that it makes any difference.

*Ta-152 H-1 Aerodynamics at SL*

Lift: 

L = 1.45*23.3*.5*1.164*125^2 = 307232.344

Drag:

Cdi = (1.45^2)/(pi*8.94*.80) = 0.0935747393
Cd0 = -Unknown-

D = 0.0935747393*23.3*.5*1.164*125^2 = 19827.0252

L/D ratio = 15.49
L/W ratio = 64.68

*Spitfire Mk.XIV aerodynamics at SL*

Lift:

L = 1.35*22.48*.5*1.164*125^2 = 275977.125

Drag:

Cdi = (1.35^2)/(pi*5.61*.83) = 0.124588142
Cd0 = -Not included-

D = 0.124588142*22.48*.5*1.164*125^2 = 25469.2424

L/D ratio = 10.83
L/W ratio = 71.68

____________________________

Ta-152 H-1 L/D ratio = 15.49 
Spitfire Mk.XIV L/D ratio = 10.83

Ta-152 H-1 L/W ratio = 64.68
Spitfire Mk.XIV L/W ratio = 71.68

So thats 43% more lift pr. drag for the Ta-152 H-1 compared to the Spitfire Mk.XIV, and a mere 11% more lift pr. weight for the Spitfire Mk.XIV compared to the Ta-152 H-1.

Surprise surprise !! Its the same result !


So finally here's some good advice for you Hop; Stop cherry picking and stop acting like you know something you do not !


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## AV8 (May 17, 2007)

Soren, maybe you should learn to spell the word "you're" in your signature?

I wonder if there's a "coefficient of spelling?" If so, I'd probably fail it along with Soren ... Ha!


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## AV8 (May 17, 2007)

Hey Hop,

I'm with you. The only time the max CL for gliding flight is important is when the plane is landing, gliding down from height, the engine has failed, has been shot into nonworking order by either friendly or hostile fire, or has run out of gas or oil. 

If any of the above happen, a nylon parachute letdown has a much better chance of survival than riding a WWII piston fighter down to the ground .. unless there is a convenient field around long enough to land safely on.

Personally, If I were investigating a piston fighter and wanted to know performance, I'd be intersted in the lift coefficient at both full power and war emergency power. The rest aren't very important to combat. Almost anyone can be trained to fly a WWII fighter in the takeoff and landing pattern safely, so the gliding coefficient of lift would never enter my mind unless I were the designer ...

Soren must be interested in which airframe is more efficient as a glider. Given that neither the Mustang, Spitfire, or Fw 190 / Ta 152 were ever intended as gliders, it makes me wonder what he is trying to analyze. Also, it is unimportant to combat.

Were you as perplexed as I was about that?


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## Soren (May 19, 2007)

For Christs sake, correcting an old mispelling so small that I myself hadn't even noticed it  You're desperate AV8, really desperate ! 

Anyway its quite clear you're as clueless about aerodynamics as Hop is.

The L/D ratio is EXTREMELY important in combat as its one of the dictating factors to which a/c retains energy best in turns, and which a/c that has to disengage to regain energy first. You two ofcourse are clueless about this fact. 

We don't have the exact Clmax figures for both fighters at full power, if we did they would be used - but its irrelevant cause the increase in CLmax caused by the propwash would be very similar for both a/c (again something you two probably had absolutely no clue about). But since you absolutely want to address this factor I can tell you that the Ta-152's prop is larger and covers more of the wing, leading to a slightly bigger increase in CLmax.

So AV8 I'll give you the same advice as Hop; Stop acting like you know something you do not !

PS: You're a former member right AV8 ?


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## DerAdlerIstGelandet (May 19, 2007)

Yeap he is GregP.


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## Kurfürst (May 20, 2007)

Hop said:


> Um, Kurfurst, you've reposted the chart that shows exactly what I said. Apart from the Spitfire at 30 lbs stick force that you've drawn in, that is.
> 
> 
> 
> ...


----------



## Hop (May 23, 2007)

> Hop,
> 
> You've screwed up your calculations big time.



Actually Soren I've got my calculations correct, because I am using the correct units. You got yours wrong because you mixed the units.



> And besides it is CLmax you want to be looking at, not CL in straight flight.



Firstly, it's not CL in straight flight, unless you believe a plane flies straight whilst generating twice as much lift as it weighs. 

And Cl max is a maximum turn, riding the stall. If I used your original figure of 
a turn at 600 km/h, we'd get rather a sharp turn.

The problem with your new calculations is that the planes are turning at very different rates. The Ta 152 is generating 6.6 times its own weight in lift, the Spitfire 7.4 times its own weight. The Spitfire is therefore turning much tighter in your comparison.



> And as to thrust, well sorry but you can leave HP out of this, its actual thrust we're talking about here



Thrust is just power multiplied by prop efficiency, so you most certainly cannot leave out HP.



> and the Ta-152H's new prop provided over 300 kg more thrust than the FW-190A's and with 50 less PS.



Source for this claim? 

It might be true that at some specific speed the Ta 152 prop was much more efficient than the 190A's; I've heard anecdotally that the 190 A had very poor efficiency at very low speed, probably caused by not enough pitch adjustment. But if it is true that's due to a problem with the 190's prop, not due to any remarkable breakthrough in the Ta's.

Prop efficiency was pretty similar between the allies and the Germans, if you want to claim that the Ta's was that much more efficient then you really need to provide a source, not just state your opinion as fact.



> And as to the Oswald efficiency factor, what in the wolrd makes you think that the Spit's has a figure which is higher by more than 0.03 ???!



What in the world makes you think it's not? The truth is you are just guessing, and forgive me for pointing out that it's just guesswork.



> Oh and about why you only use free float figures, simple, CL changes are variable with thrust and how big a part of the wing it covers - using free float figures allows us to figure out the effectiveness of the body itself.



Which would of course be a more accurate way of doing things if we were trying to work out the best turnfighter with engine off. With engine on, though, the CL is very different, and planes tend to fight with engine on (and on max, usually).

That's why the RAE also gave the CL max figure for the Spitfire at full power. The figure for the Spitfire XIV will of course be a bit different, but it's going to be far closer to the power on figure for an earlier Spit than it is to the same earlier Spitfire's power off figure.



> This time I'll also do speed figures in m/s like you, but again not that it makes any difference.



It does of course because it allows you to work out how tightly they are turning. That's the sort of reason they use consistent figures in equations.



> Surprise surprise !! Its the same result !



It is, but of course we can now use adjusted CL figures to get the same turn rate for both planes, rather than working out a turn in which the Spitfire is turning much tighter than the Ta.

I'll use your figures, even the non standard pressure:

Ta 152 - lift = 6.6 times weight

Spitfire - 37418 = CL*22.48*.5*1.164*125^2 = 247357
CL required to match Ta 15 turn = 1.21

Cdi:
Ta 152 0.0935747393

Spitfire: Cdi = (1.21^2)/(pi*5.61*.83) = 0.1

Drag:

Ta 152 = 19,827

Spitfire = D = 0.1*22.48*.5*1.164*125^2 = 20,443

The Spitfire has about 3% more induced drag, and at least 10% more power. 



> So finally here's some good advice for you Hop; Stop cherry picking and stop acting like you know something you do not !



Soren, there are few as cringe worthy as watching someone who has got things wrong mistakenly criticising something that's correct, and doing it in a patronising tone.

Next time, do the maths properly (which means using the correct units), work out the results with both aircraft pulling the same turn, and don't make assumptions like more power doesn't mean more thrust.


Brain, you accused me of hypocrisy. I asked you for some evidence to support such a charge. You haven't provided any. I'll ask again. Some evidence please, or an apology. Either will do me.


----------



## Hop (May 23, 2007)

> Brilliant, we know now that the NACA graph above is based on a RAE test of a MkV, which MkV's roll rate results are far above any other Spitfire's roll rate.



No, it's above earlier Spitfires. We know from AFDU tests that the Spitfire rolled as well as the P-47, and better than the Mustang, so we know that the figures you are trying to sell as representative cannot be true, otherwise how could they say the Spitfire rolled as well as the P-47 and better than the Mustang?

There's also the Dave Southwood comment you keep posting:



> A 1g 360 degree full stick roll in a clipped wing Spit IX at 250 KIAS and 5000 ft takes 3 seconds



That is of course 120 deg/sec at 288 mph, which is a bit better than NACA 868, because roll rate increases with altitude, even at the same IAS.



> Like :
> 
> 1, It's made by an impartial organisation
> 2, In a professional manner
> ...



In other words you can't actually refute the argument? Not surprising, really, as they are all facts. 



> Dear Hop, you put forward a Bf 109F-2 roll rate test as gospel, and aircraft that was produced somewhere in 1940 or 1941, and was tested after 3 years of use, in the end of the 1944. And you say it's represenetative for the type.



It contains the best figures I know of the 109 roll rate. And actually YOU have been posting it around the net. eg ROLLRATE TESTING: Bf109K - Topic Powered by eve community

I based my acceptance of it on your attitude, as you claim to be something of an expert on the 109.



> Yet, when it comes to a Spitfire, you argue that a plane that was freshly produced in April 1941, and was immidiately delivered afterwards to the US and tested in December 1941 is not representative because the aircraft was 'worn out' for which you give us a quote from a pilot which doesn't tell if it's the same plane at all, if the comment refer to the state before or after the test,



I believe he does tell us it's the same plane, and it is obviously before the tests because Tuck saw it in the autumn of 1941, and was back in the UK before the end of the year. NACA note the tests began on the 30th December, iirc.



> Dear Hop, can you answer us why do you dismiss an American test on a brand new Spitfire



How is it brand new if it had its first flight in April, and tests began right at the end of December? As Tuck said, "almost every pilot in the air corps had had a go on her", which is probably not much of an exaggeration for a Spitfire in the US in 1941.



> What do you think was 'worn out' more, a 109F in the end of 1944 or a Mk V in the end of 1941 ?



Depends on maintenance, doesn't it. I imagine the Germans knew exactly how to rig the 109, I'm not so sure the US mechanics in the US in 1941 were as familiar with the Spitfire.

_I_ don't take foreign tests of aircraft as gospel because they usually show very different performance figures, which is your position when foreign tests show German aircraft doing badly.



> .We don't...? I am sorry but this is a cheapo trick, as it's written there and you've already admited it was discussed before, so you must know it.
> 
> Again :
> 
> ...



No, we know the ailerons were metal covered. We do not know if they were the standard metal ailerons fitted to most Spitfire Vs, and all later Spits. The dates suggest the Spitfire in question would not have been produced with metal covered ailerons, and it was transferred to the US within days of being produced. 

The problem is, metal ailerons were not standard on the Spitfire in April 1941, as Sholto Douglas points out.

We also don't know if metal ailerons required different aileron circuit rigging, and if so, if it was done on this Spitfire.

That's the disadvantage of foreign testing, which is usually conducted without the proper manufacturer/operator support.



> Of course but what does it prove? Nothing apart from NACA used a RAE graph in one of it's reports. NACA didn't test roll rate up to 400 mph, though I doubt RAE would,



You doubt they would what? Test up to 400? As they clearly say the results are as tested, then they must have. As they criticise NACA for only testing up to 295, and neglecting the "vital region around 400 mph", then it would be rather silly of them not to do so themselves.



> RAE seems to have actually tested the effect of clipping of wings on the Spitfire, and the findings are quite different than what the Spit cliiped/unclipped roll rates displayed on the NACA chart suggest, ie. that there would be a linear huge rate of roll increase at all speeds. Quite the contrary, ie.



Well, they went on to clip large numbers, so they must have found some benefit. They also note that there is a large benefit on those Spitfires with heavier than average ailerons, which suggests NACA 868 actually shows the results for a poor example.



> Or compare another RAE trial with a Spit V with the Spit V on the NACA 868



Which Spitfire V? Would this by any chance be another Spitfire Va? And would it be an earlier test than the one published in NACA 868? I suspect the answer is yes to both.



> That means either the tested aircraft was an exceptionally good example of it's type, or perhaps a testbed with some experimental aileron fitting.



Only they quote it as representative of the Spitfire in the Fw 190 test.



> The RAE, Hop?



Sorry, my mistake. AFDU. Happy?



> Roll performance is similar to a Hurricane or elliptical wing tipped Spitfire. A full stick roll through 360 degrees at 460kph takes 4 to 4.5 seconds without using rudder,



Of course, if you look at the graph you will see the 109 _is_ similar to the Spitfire around the 460 km/h (280 mph) mark. There is very little to chose between them at those typical display speeds. I make it about 3 deg different, according to NACA 868 and the German figures you have drawn on.

It's when you go faster or slower the 109 shows itself to have extremely poor aileron control, as shown by these reports, and by anecdotal evidence from the war years.



> Hop we all understand that in your eyes, the Spitfire did everything better than any other aircraft, it had greater mileage than the Mustang, dived to greater speed than the P-47, rolled with the FW 190,



No Kurfurst those are your lies, not things I have claimed (apart from the mach speeds vs P-47).



> not to mention your latest theory I've read that the RAF was doing a lot more combat against the Luftwaffe than the USAAF in the late 1943,



See for example the Fighter Command War Diaries. 



> This is quite irrelevant to the subject I think.



What, you mean the fact that in comparison trials the Spitfire was found to roll as well as the P-47, and a bit better than the Mustang? Hardly, as it gives the lie to your claims. 

But, seeing as you are now claiming that foreign testing of aircraft _is_ to be taken at face value, here are the AFDU trials against 109s:



> The Spitfire XIV rolls much more quickly.





> .Here again the Spitfire has a marked advantage at all speeds.



Now personally I take such tests with a grain of salt, not that they are _necessarily_ wrong, just that they can't be relied on. But as Kurfurst insists such tests _can_ be relied on...


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## Kurfürst (May 23, 2007)

So, I can summerize your POV, you dismiss every single Spitfire roll test done by the NACA, RAE, the RAAF, the RAF, except the single test that's details and conditions are unknown but are the most favourable to the Spitfire and in disagreement with the findings of other tests by the same organisation, RAE?

Also, you definietely struggle to dismiss a test done on a Spitfire V, on the basis that it's metal ailerons were not metal aileron, US mechanics were probably jerks anyway, the aircraft was 6 months old when tested, and it didn't have the wing strenghtening of the later models.

Yet, you want to push forward a roll test on a 3-4 year old 109F-2, which didn't have the wing strenghtening of later models either, as a gospel ?

Is that correct?



> Well, they went on to clip large numbers, so they must have found some benefit. They also note that there is a large benefit on those Spitfires with heavier than average ailerons, which suggests NACA 868 actually shows the results for a poor example.


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## bomber (May 23, 2007)

guys... I'm modelling the flight model of a Spit V for Targetware flight sim..

I used the testing report found on this site... if however there's some doubt as to it's validity/accuracy could you point me in the direction of an indepedant test.. maybe a Rolls Royce Hucknall one if they did one.

Also the engine torque gives a pronounced anti-clockwise rotation, was the time taken for this rotation ever recorded ?

And whilst I'm at it... would the ground crew not attempt to dampen this torque down with adjustments to centre stick aleron deflection ?

Regards

Simon


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## Soren (May 23, 2007)

> Actually Soren I've got my calculations correct, because I am using the correct units.



What a big load of rubbish Hop - you need to learn math !



> You got yours wrong because you mixed the units.



Huh ?!! I dare you to point it out !

Yeah thats right, there has been no mixing of units at all !



> Firstly, it's not CL in straight flight, unless you believe a plane flies straight whilst generating twice as much lift as it weighs.



Wow ! And just when I thought it couldn't get any worse with your wild imaginations !

Listen Hop, a CL of 0.5 is not something you get whilst turning goofball, and that silly remark of yours just supports the fact that you know nothing of what you're talking about. 

Oh and btw generating a 2:1 lift to weight ratio is very normal in straight flight - so yes I do believe that. But hey keep it coming Hop, this is funny 



> The problem with your new calculations is that the planes are turning at very different rates. The Ta 152 is generating 6.6 times its own weight in lift, the Spitfire 7.4 times its own weight. The Spitfire is therefore turning much tighter in your comparison.



There is no problem with the math I presented, the problem lies with you Hop and your total lack of knowledge on aerodynamics. The Spitfire isn't turning much tighter at all, its got an 11% percent advantage in lift pr. weight which gives it a slightly higher initial turn rate, however the much higher drag makes sure that this advantage goes instinct quickly and is completely overtaken by the Ta-152H which holds an advantage in sustained turn rate over the Spitfire.



> What in the world makes you think it's not? The truth is you are just guessing, and forgive me for pointing out that it's just guesswork.



Wrong again Hop !

I'm not just making wild guesses here, I'm basing my assumption on the 'e' figures in a graph comparing high AR wings of the same shape as the Ta-152's with a fully elliptical wing with no twist.



> It does of course because it allows you to work out how tightly they are turning. That's the sort of reason they use consistent figures in equations.



You just can't stop with your ever deeeper quest into denial can you ?! 

Its there right infront of you man ! The exact same difference in percentages as when I used km/h instead of m/s !

For crying out loud ! 

And as to pressure - at SL at 15 Celcius it is 1.164 exactly. Oh and btw, using different pressures in the equation doesn't change anything between the Ta-152 and Spit.



> Source for this claim?



But ofcourse: 




And I repeat: Hop, stop cherry picking and stop acting like you know something you do not !


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## Jackson (May 23, 2007)

Hop and Kurfirst..

you make excellent points..


KEEP UP THE GREAT WORK



I believe everyone knows the Spitfire was way more manueverable than the 190 or the 109


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## Hop (May 23, 2007)

> You got yours wrong because you mixed the units.
> Huh ?!! I dare you to point it out !
> Yeah thats right, there has been no mixing of units at all !



You used Km/h instead of m/s. That gives you the wrong result.



> Listen Hop, a CL of 0.5 is not something you get whilst turning goofball, and that silly remark of yours just supports the fact that you know nothing of what you're talking about.



Um, you can turn at different rates. You can most certainly turn at a CL of 0.5, if that provides more lift than you need for level flight.



> Oh and btw generating a 2:1 lift to weight ratio is very normal in straight flight - so yes I do believe that.



Um, do you understand physics at all? If lift exceeds weight, the plane is going to be moving in the direction of lift. 



> There is no problem with the math I presented, the problem lies with you Hop and your total lack of knowledge on aerodynamics. The Spitfire isn't turning much tighter at all, its got an 11% percent advantage in lift pr. weight which gives it a slightly higher initial turn rate,



No. If you are generating more lift/weight, you are pulling more G. Go and look up the concept of bank angle and G.

In the example you gave, the Spitfire was pulling 7.4 G, the Ta 152 6.6 G.



> Wrong again Hop !
> 
> I'm not just making wild guesses here, I'm basing my assumption on the 'e' figures in a graph comparing high AR wings of the same shape as the Ta-152's with a fully elliptical wing with no twist.



In other words, you are guessing. You don't have Oswald efficiency figures for either aircraft, just rough figures for similar wing shapes.



> Its there right infront of you man ! The exact same difference in percentages as when I used km/h instead of m/s !



The percentage difference is there, but absolute figures are not. 



> And as to pressure - at SL at 15 Celcius it is 1.164 exactly.



International standard atmosphere density is 1.225 at sea level. It's not worth arguing over, though, as your figure isn't "wrong", just non-standard.



> Oh and btw, using different pressures in the equation doesn't change anything between the Ta-152 and Spit.



No, and I never said it did. That's why I used it with the figures you'd created, rather than recalculate. 



> So, I can summerize your POV, you dismiss every single Spitfire roll test done by the NACA, RAE, the RAAF, the RAF, except the single test that's details and conditions are unknown but are the most favourable to the Spitfire and in disagreement with the findings of other tests by the same organisation, RAE?



No. I just generally believe that later tests tend to show a more accurate picture for later aircraft. Especially as the AFDU findings make no sense when using the figures you are trying to portray as typical for Spitfires, but do make sense compared to the figures in NACA 868.

Now, as to the question of why the earlier figures are different to the later ones, I believe I have found the answer, or at least a partial answer.

There is an earlier test of the Spitfire roll rate by the RAE, dated April 1941. They say that 65% of the aileron effectiveness is lost to wing twist, exactly the same figure the RAE reported to NACA. The report also says that due to wing twist, the aileron reversal speed was 475 - 480 mph.

The later test, the one that produced the figures you hate so much, notes that reversal speed is 580 mph for the standard wing, 660 mph for the clipped wing.


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## Soren (May 24, 2007)

Hop said:


> You used Km/h instead of m/s. That gives you the wrong result.



No it doesn't Hop, what we were looking for was the difference between both a/c and as you can see the difference is the same wether you use km/h or m/s.




> Um, you can turn at different rates. You can most certainly turn at a CL of 0.5, if that provides more lift than you need for level flight.



Listen if Clmax is 1.36 then you're not really turning very well at 0.5 now are you ?? 

What we want to be looking at is CLmax, as this is the region both a/c are most likely going to reach when they turn fight each other. 



> Um, do you understand physics at all? If lift exceeds weight, the plane is going to be moving in the direction of lift.





Yes I do understand physics, however you're having big trouble indeed Hop. Ever wondered why a/c need to adjust pitch settings as speed goes up ?? Or are you under the impression that as speed increases lift stayes the same ??

Keep it coming Hop! 



> No. If you are generating more lift/weight, you are pulling more G. Go and look up the concept of bank angle and G.



For Christ's sake what is it you don't understand man ?!! 

Yes like I said a higher L/W ratio gives you a higher INITIAL turn rate, however since the Spitfire has got loads more drag pr. lift its going to loose out quickly in a sustained turn fight.



> In other words, you are guessing. You don't have Oswald efficiency figures for either aircraft, just rough figures for similar wing shapes.



Rough figures ?? No, exact figures Hop. But yes there is a little guesswork involved as we don't have the 'e' figure for both aircraft, however knowing the difference in 'e' of a completely elliptical with no twist and an AR of 6, and also knowing what approximate effect leading edge guns have on 'e' I can make a reasonable and educated guess. 



> The percentage difference is there, but absolute figures are not.



Like I said, we're calculating the difference between two a/c here, so therefore it doesn't matter wether its in km/h or m/s, the difference in percentages is the same.



> International standard atmosphere density is 1.225 at sea level. It's not worth arguing over, though, as your figure isn't "wrong", just non-standard.



There can be many reasons why the international std. is different, but again wether we use the international std. figure or the other more regional one doesn't matter, the difference stayes the same.


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## Hop (May 25, 2007)

> No it doesn't Hop, what we were looking for was the difference between both a/c and as you can see the difference is the same wether you use km/h or m/s.


You could use cubits per sar, the proportion would still be the same, but you will not get even a roughly correct idea of rate of turn.

Look, Soren, you claimed I had my figures wrong. I didn't. You did so in an extremely patronising way, which is why I pointed out you had your units wrong. Accept it, move on.



> Listen if Clmax is 1.36 then you're not really turning very well at 0.5 now are you ??



Depends on speed, doesn't it? Just doing the rough calc:

Spitfire - 37418 = 0.5*22.48*.5*1.164*125^2 = 2.7 G. So at 125 m/s, the Spitfire is pulling not far off 3 Gs at a CL of 0.5.

If we use the 600 km/h you used the first time:

Spitfire - 37418 = 0.5*22.48*.5*1.164*167^2 = 4.9 G.



> What we want to be looking at is CLmax, as this is the region both a/c are most likely going to reach when they turn fight each other.



It really does depend on speed. You try reaching too high a Cl at too high a speed, you are going to rip the wings off.

For example, at the 600 km/h you originally used:

Spitfire - 37418 = 1.4*22.48*.5*1.164*167^2 = 13.7 G. Think you are going to be pulling that in a turn fight?

More to the point, CL max is usually unsustainable (think you can sustain 4.9 G in a WW2 fighter?)



> Yes I do understand physics, however you're having big trouble indeed Hop. Ever wondered why a/c need to adjust pitch settings as speed goes up ?? Or are you under the impression that as speed increases lift stayes the same ??



No. What you wrote was:


> Oh and btw generating a 2:1 lift to weight ratio is very normal in straight flight - so yes I do believe that.



If you are generating lift equal to twice you weight, you will not be flying in a straight line, it's a physical impossibility. If you increase speed, you decrease the angle of attack so that lift continues to equal weight. At least, if you want to continue flying straight you do.



> For Christ's sake what is it you don't understand man ?!!



I don't understand what you believe. I only understand the physics. When someone approaches the discussion with a wrong concept, it can be very hard to understand what their concept is.



> Yes like I said a higher L/W ratio gives you a higher INITIAL turn rate,



You gave calculations showing the Spitfire with a substantially higher lift/weight ratio. That means the Spitfire, in your calculations, was turning tighter. 

It will, of course, generate considerably more drag than the Ta 152 if it is turning much tighter than the Ta152.



> however since the Spitfire has got loads more drag pr. lift its going to loose out quickly in a sustained turn fight.



It doesn't have "loads" more, it has approx 3% more, a difference that is more than made up by the greater power (and much greater power to weight, incidentally) of the Spitfire.

Having written that, I have got a grasp on your wrong concept. 

Induced drag increases with the square of the Cl. That means the tighter a plane turns, the less efficient its lift production becomes.

First, the Ta 152 as a baselineplease check all these calculations, I did them the first time using a CL of 1.42 for the Ta 152, and as I had intended to do them at the 1.45 CL you wanted, I redid them all, so please check if any mistakes have crept in)

Lift = 1.45 * 23.3 * .5 * 1.225 * 125^2
Lift = 323 333 N. That's 6.95 times weight. 

Cdi = (1.45^2)/(3.142*8.94*.80) = 0.0936

Drag = 0.0936*23.3*.5*1.225*125^2 = 20,872

Lift/drag = 15.5/1 

Now, you worked out the Spitfire at a Cl of 1.35:

Lift = 1.35 * 22.48 * .5 * 1.225 * 125^2
Lift = 290,440 N. That's 7.76 times weight. 

Cdi = (1.35^2)/(3.142 * 5.61 * .83) = 0.1246

Drag = 0.1246*22.48*.5*1.225*125^2 = 26 807

Lift/drag = 10.8/1

From this you come up with the Spitfire having 43% more drag/lift. Fair enough.

However, the error is that the Spitfire is turning tighter here. It's generating more lift in relation to its weight, in other words it's pulling more G. When you reduce the turn to the same G as the Ta 152, you get a very different figure:

Lift = 1.21 * 22.48 * .5 * 1.225 * 125^2
Lift = 260 320 N. That's 6.95 times weight, the same turn as the Ta 152. 

Cdi = (1.21^2)/(3.142 * 5.61 * .83) = 0.1

Drag = 0.1*22.48*.5*1.225*125^2 = 21 514

Lift/drag = 12.1/1 

See how when it's only turning as tightly as the Ta 152, the lift/drag ratio for the Spitfire improves. But wait, there's more.



> however since the Spitfire has got loads more drag pr. lift its going to loose out quickly in a sustained turn fight



Ok. The Ta 152 now has approx 30% lift/drag advantage over the Spitfire. So the Ta 152 still has a huge advantage, right?

The problem is, the Spitfire is LIGHTER. It doesn't have to generate the same amount of lift as the Ta 152 to match its turn. In fact, if you look at both planes making the same turn above, the drag figures are:

Ta 152 - 20,872
Spitfire - 21,514

The Spitfire has 3% more induced drag when making the same turn as the Ta 152.

Now, those figures are nowhere near exact, of course, and as we don't have exact figures for Oswald efficiency, and don't have parasitic drag figures at all, there's no point in trying to make them more exact. But the induced drag figures for the 2 aircraft are very, very close, and the Spitfire still has that power advantage.



> Rough figures ?? No, exact figures Hop. But yes there is a little guesswork involved as we don't have the 'e' figure for both aircraft,



Exact figures, plus or minus a guess?



> however knowing the difference in 'e' of a completely elliptical with no twist and an AR of 6, and also knowing what approximate effect leading edge guns have on 'e' I can make a reasonable and educated guess.



So a guess, as I said.



> There can be many reasons why the international std. is different, but again wether we use the international std. figure or the other more regional one doesn't matter, the difference stayes the same.



No, it doesn't, which is why I didn't say you had the "wrong" density figure, just not standard atmosphere.


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## Kurfürst (May 25, 2007)

Hop said:


> No. I just generally believe that later tests tend to show a more accurate picture for later aircraft.



Hop, even if you rephrase it that just still means you're dismissing every single test apart from the one that's conditions are totally unknown, on the basis it has the highest figures for the Spitfire, and even if it is in conflict with all the others.

Besides if go by the latest test, I guess we have to go by this. It's in rather serious disagreement with the earlier one you're waving.

Apart from that, it's done with Mk XIIs, which were having the most advanced airframe the Spitfire ever got and the stiffest wings etc. Yet look at the conclusions and the characteristics - clipping the wing only seems to improve aircraft with poor ailerons (which are still not as good as normal wings with good ailerons), and it's not a linear improvement, appearantly having an effect at high speed but little at other speeds - quite unlike RAE's earlier trials(?) seem to show.

http://i38.photobucket.com/albums/e133/Kurfurst/Spit_clipped.jpg[/IMG
[ATTACH=full]389360[/ATTACH]

Add to that the quoted Mk V pilot's opinion, the vast majority seems to disagree with your RAE's chart's notion that the clipped wing Spit can come even close to the FW 190A in terms of roll.

[QUOTE] Especially as the AFDU findings make no sense when using the figures you are trying to portray as typical for Spitfires, but do make sense compared to the figures in NACA 868.[/QUOTE]

Well, the ADFU trials often doesn't make much sense at all, even you've said it in the past.

For example, this compares the Mk XIV Spitfire at +18 to the Bf 109G-6/U2 with gunpods and 1.3ata :

[IMG]Climb
25.........When both aircraft are at 16,000 feet (the rated altitude of the Me.109), there is little to choose between the climbing performance of the two aircraft,

The problem is that 16 000 feet was never the 109G's rated altitude, and frankly it's the most flattering trials for for the 109G, if even the most draggiest version, burdened with gunpods, running at a mere 1300 HP output can match the Mk XIV Spitfire at 2035 HP output.

Yet if we look at the climb graphs, we find the XIV climbs at 3700 fet/min at 16000 feet, the 109G-6 with gondolas is around 2400 feet/min.

So who to believe, AFDU's 'rather vaguely expressed opinions', as you called them before, or the documented results of trials ? 

I really don't wish to argue on this, after all, you showed numerous times that you can argue the facts indefinietely, and the I think he documents were posted and everybody can just make their own conclusions.


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## Soren (May 25, 2007)

Hop,

Your new calculations are acceptable, however I have been given something by a friend that changes everything:

*NACA 23000 series airfoil characteristics at AR = 6*




Knowing this I think its safe to say that the Ta-152's real Clmax is a good deal higher than my assumption. This also explains the Fw-190 G-2's ability to turn with the Mustang Mk.III.

Lets plot in the new CL figure then:

*Ta-152 H-1*

Lift (L): 1.6 * 23.3 * .5 * 1.225 * 125^2 = 356781.25

Induced Drag (Cdi): (1.6^2)/(pi*8.94*.80) = 0.113936425

Total Drag (D): 0.113936425 * 23.3 * .5 * 1.225 * 125^2 = 25406.4876

L/D ratio = *14.04*
L/W ratio = *7.49*

*Spitfire Mk.XIV*

Lift (L): 1.36 * 22.48 * .5 * 1.225 * 125^2 = 292591.25

Induced Drag (Cdi): (1.36^2)/(pi*5.61*.83) = 0.126440729

Total Drag (D): 0.126440729 * 22.48 * .5 * 1.225 * 125^2 = 27202.5375

L/D ratio = *10.75*
L/W ratio = *7.58*

At Clmax this gives the Ta-152 H-1 a 30% advantage in Lift pr. amount of drag produced over the Spitfire Mk.XIV, and the Spitfire a 1.2% advantage in lift pr. amount of weight over the Ta-152 H-1.

At the same G the Ta-152 H-1 holds a 29% advantage in L/D ratio, and a 4.4% advantage in total induced drag.



Hop said:


> Depends on speed, doesn't it? Just doing the rough calc:



Does a turn fight often take place at high speed ?? No.



> Spitfire - 37418 = 1.4*22.48*.5*1.164*167^2 = 13.7 G. Think you are going to be pulling that in a turn fight?



No, exactly !

The reason I used 600 km/h was simply to illustrate that speed doesn't help the Spitfire.



> More to the point, CL max is usually unsustainable (think you can sustain 4.9 G in a WW2 fighter?)



Which is why the L/D ratio is so important! 



> If you are generating lift equal to twice you weight, you will not be flying in a straight line, it's a physical impossibility. If you increase speed, you decrease the angle of attack so that lift continues to equal weight. At least, if you want to continue flying straight you do.



Man you're anal !

At 600 km/h for example I guarantee you that Lift is way higher than weight, that your wing needs to be pointed slightly downward is to keep you from sky rocketing (The engine helps alot pulling the plane down as-well), however you are going in a straight line - hence why many a/c have their wings pointing slightly downwards - to ensure good vision from the cockpit.



> From this you come up with the Spitfire having 43% more drag/lift. Fair enough.
> 
> However, the error is that the Spitfire is turning tighter here. It's generating more lift in relation to its weight, in other words it's pulling more G.



Hop, it'll only be capable of pulling more G for a short while, which means it might just be capable of pointing its nose ahead of the Ta-152 for a very short while before losing too much speed - the Ta-152 having a higher constant turn rate.



> Now, those figures are nowhere near exact, of course, and as we don't have exact figures for Oswald efficiency, and don't have parasitic drag figures at all, there's no point in trying to make them more exact. But the induced drag figures for the 2 aircraft are very, very close, and the Spitfire still has that power advantage.



Power advantage ? Hop, the Ta-152H-1 is faster on the deck than the Spitfire Mk.XIV and with less power.

Exactly why an advantage in engine power doesn't mean an advantage in thrust.

[qoute]Exact figures, plus or minus a guess?[/qoute]

Its experitmental figures from NACA Hop, so they should be exact.



> So a guess, as I said.



A educated guess, yes.


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## Jackson (May 25, 2007)

meebbe we should do a poll amongst the members

more manuverable? 

Spit vs Bf 109


http://www.ww2aircraft.net/forum/polls/bf-109-vs-spitfire-3406-13.html

it has been done


the Spit won


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## Jackson (May 25, 2007)

Mustang thread...the Ta 152 was immaterial as to combat


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## davparlr (May 26, 2007)

Jackson said:


> Mustang thread...the Ta 152 was immaterial as to combat


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## Soundbreaker Welch? (May 27, 2007)

I guess he's means the Mustang saw combat in greater numbers.


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## Rapecq (May 27, 2007)

Hi

Wow, i'm impressed - so many interesting information, statistics and technical characteristics. Guys, I've got one question related to P-51 maneuvrability - what about stall characteristics of P-51 ?? I've read that laminar wing could stall much more violently than conventional wing - is that true ?? I alse read words of Feldwebel(T/Sgt) Rudi Driebe form 10.Staffel, III/JG 301 who have flown Ta 152. He said:
"During dogfights the P-51 would turn very sharply and fire its a guns almost immediately(...)".
Well, I'm confused . So can P-51 turn sharply without violent stalling ?? and what about Bf 109 G in tight turning combat?? Which of those aircraft could stall earlier ??

Regards


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## Soren (May 27, 2007)

Rapecq said:


> Hi
> 
> Wow, i'm impressed - so many interesting information, statistics and technical characteristics. Guys, I've got one question related to P-51 maneuvrability - what about stall characteristics of P-51 ?? I've read that laminar wing could stall much more violently than conventional wing - is that true ??



Yes it is.



> I alse read words of Feldwebel(T/Sgt) Rudi Driebe form 10.Staffel, III/JG 301 who have flown Ta 152. He said:
> "During dogfights the P-51 would turn very sharply and fire its a guns almost immediately(...)".



Whats he's talking about here is a quick deflection shot, a tactic often used by the Fw-190 against the Spitfire.



> Well, I'm confused . So can P-51 turn sharply without violent stalling ??



The P-51 can turn until its Clmax is reached, which it is at a rather low AoA, which means its got the nasty tendency of stalling suddenly, violently and without warning in turns.



> and what about Bf 109 G in tight turning combat?? Which of those aircraft could stall earlier ??



The P-51 will stall much much sooner than the Bf-109G in a turnfight.


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## AV8 (May 28, 2007)

About the P-51 stalling much sooner in a turning fight, not true.

Our museum flies P-51Ds and Spanish Casas (Me 109G with a Merlin). The Casa loses energy quickly in hard turns. The P-51D doesn't.

In flight, the P-51D will easily turn with the Casa and close except at very low speeds, and low speeds are not included in combat maneuvers. So ... if the speed DID get very low, then yes, the P-51D will stall a few mph sooner. The message is clear to the Mustang pilot, don't turn with a 109 at 140 mph or less. Mustang pilots learned that early.

The only real advantage the Casa has is sustained rate of climb. In a zoom climb, the P-51D is better.


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## davparlr (May 29, 2007)

AV8 said:


> About the P-51 stalling much sooner in a turning fight, not true.
> 
> Our museum flies P-51Ds and Spanish Casas (Me 109G with a Merlin). The Casa loses energy quickly in hard turns. The P-51D doesn't.
> 
> ...



Good posting.

Just like the US fighters fought the Zero in the Pacific, in ETO, if the Mustang used its speed and kept it up, it would lead the dance, i.e. it would initiate and depart the combat a will, or manipulate energy to take advantage. No wise Mustang pilot would fight at Max Cl, or close to stall. Its advantage did not lie there. It had much more powerful tools elsewhere.


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## drgondog (May 29, 2007)

Kurfurst - if you want to bring in the 1945 models of Fw190s and Me109s, bring in the 51H which was in production in March 1945 - it was 900 pounds lighter and 30kts faster than the 51D, out accelerated the 51D, out turned, outclimbed it and rolled faster.

The problem with these discussions, as you say, is that the Luftwaffe also did not have the latest variants of allied fighters in good shape to compare against the 190D's and 109G-10 thru K4's... at least I have not yet seen such reports out of Rechlin. 

The only sources for the comparisons that help us be objective are the Post War tests - Mike Williams website is the best collection I have seen so far - and still remain suspect because of all the variables and time it would take to map turn, roll, acceleration, speed, initial climb, etc at say 5 different altitudes

Your comments above - "Overall, probably the best desrcription of the Mustang would be a fair, good over-all fighter that's best quality was speed and range, and was not exceedngly great or poor in any other regard. A jack of all trades, master of none." 

The one trait it had was to dominate the Luftwaffe in the skies over Germany, against, I suppose, Luftwaffe a/c that were superior in every way except speed and range? 

Most historians would say they (P-51) fared exceedingly well against the best the Luftwaffe had to offer in places like Warsaw or Posnen or Ploesti from Italy or England - places where 109s and 190s (and Spits and Tempest and F4U's) could not ever be based similarly, and STILL fight on even or better conditions with a load of fuel that had to take them 500-600 miles more to return to base.

Last, if 51D acceleration at any altitude was close, say to a 109G-10 or Fw190D, and turning radius at HIGH speed was the same or slightly less than a 109G-10 or better than a 190D and dive acceleration and sustained speed was superior and aileron and rudder forces at high speed were superior for a 51D - then it was "only somewhere between Poor and Not Exceedingly Great"?? What is your standard for Exceedingly Great??

I will never say it was the best in anything - except taking on and defeating their "Betters" some 600 miles away from home. Imagine putting 250 gallons (or equivalent weight) of internal fuel in a 109G-10 of Fw190D9 and have it fight a 51D (or H) with 70-100 gallons of fuel or less? And have your guy fly 4 hours unders constant stress or boredome before fighting? Luftwaffe pilots did not experience that (nor did Brit or Russian - only Japanese)

These are tough debates but the performance of the Mustang should not simply be dismissed as somewhere between Poor and Exceedingly Great 

Strictly my opinion, with respect to yours

Bill


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## Rapecq (May 30, 2007)

So, to sum up - P-51D loses energy slower in turning at small AoA and much faster when the AoA is bigger ?? 

Regards,


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## davparlr (May 30, 2007)

Rapecq said:


> So, to sum up - P-51D loses energy slower in turning at small AoA and much faster when the AoA is bigger ??
> 
> Regards,



Your statement is basically correct but more like less drag at higher airspeeds (which requires lower AoA). Induced drag, drag caused by lift, is inversely affected by airspeed, that is, it affect on an airframe is reduced by the square of the airspeed. The faster you go, the less impact of induced drag. Parasite drag, drag caused by the airframe, increases by the square of the airspeed. The faster you go, the more impact it has on the aircraft. The P-51D, one of the cleanest of the common WWII aircraft, is affected less by higher speeds. In addition, higher airspeed limits the AoA that can be safely pulled due to excessive "g"s, which also benefits the lower drag P-51 wings. As a results, higher airspeeds, the Mustangs strength, is also its best friend.


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## drgondog (May 30, 2007)

Soren said:


> Yes it is.
> 
> 
> 
> ...



Not true unless in the 250 kts or lower range where a.) the stick forces for 109 ailerons are lower, and b.) where the leading edge slats are effective... or the 51 still had a LOT of fuel left in the 85 gallon fuselage tank.

The latter condition is responsible for a violent snap roll when aft cg condition took over.

At altitude and high speed the 51 would out turn a 109G or K - ditto the 190 (all versions) - and the 51 bled its speed slower because of the superior aerodynamics of the airframe and wing. Maybe a few Experten could out turn a low time Mustang pilot but it would have been all about pilot skill - not the airplane

The 109G (later models) would initially and sustained outclimb a 51 and would gain initially in a turn with a climbing turn to the right if the 51 was too close to pull deflection - that about summed up the advantage of late model 109s over 51s at altitudes above 15,000 feet. 

Both the 109 and 190 were very formidable - pilot skill equal at low and medium altitudes - but that wasn't where most of the fights were.

Regards,

Bill

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## Laurelix (Jan 30, 2021)

Brain32 said:


> Yes that WWII Aircraft Performance site has enourmus amount of very usefull documents  However please keep in mind that all those comparisons are made with captured axis planes in questionable condition and with pilots which were most certanly not as familiar with the planes of their enemy as they were with their planes
> 
> I have some Russian turn time numbers, however condition of both P51 as also the axis planes is again unknown(atleast to me)
> Turns were made at 1000m
> ...



Which P-51 tho. P-51D?


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## FLYBOYJ (Jan 30, 2021)

Laurelix said:


> Which P-51 tho. P-51D?



Be advised that this post was from 2007 and the individual who you're posing your question to has not been on this forum in a long time.


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