Escort Fighter Performance Comparison

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Especially since I also linked an article from the highly esteemed Royal Aeronautical Society covering what had been tried and so forth. Jeez.

Not to rain on your parade too much, but I posted that same article way back in post #147. ;)
 
Hi Nuuumannn.

I have nothing against Pat303 at all. He is suggesting that the Spitfire family have added fuel all around the board. People have told him it isn't exactly easy or necessarily smart to do that. Also, the aircraft was designed with a specific mission in mind, and he wants to change that, too. So, he wants to change the aircraft and the mission.

What I am saying is the missions he envisions for Spitfires as longer-range aircraft were being flown by other aircraft and, if the Brits had wanted the Spitfire to fly them, they likely could have been modified to do so.

But then the shorter missions that were flown by the Spitfires would have to flown by other aircraft that weren't nearly so suited to them as the Spitfire was. It's a case of, "OK, you want the Spitfires, who are flying short-range intercept, to fly longer-range escort and interdiction missions. OK, so who's going to fly the Spitfire missions currently being flown, and will they be as good at it as the Spitfires are? Should we gamble on that? Will the Spitfires be as good at longer-range missions as the other aircraft currently flying them are?"

Since the Spitfires never did get really long legs in large numbers, my take is they never decided to gamble with having the Spitfire missions taken over by other fighters.

I am not suggesting Pat is completely wrong. I am suggesting that it never happened in real life and since it didn't, we can speculate about it, but it is a "what if" that cannot be tried out; we are left with what the Spitfire actually did. I have no objection to a bit of extra tankage in the Spits had they actually done so. But though we might LIKE it if they had longer legs, they really didn't. And there was a reason for that. It likely has something to do with how good the Spitfire was at the missions to which it was assigned.
 
Your answer tells me you're more interested in snappy answers than information. So, go do as you want. Cheers.
All I want is to give the Spit more endurance so it can stay in the fight, there's a reason P47's and P51's racked up big numbers of kills over Europe, they could get to the fight, the Spit couldn't, a MkIX with 300 mile radius from late 42'-early 43' would have been a handy bird.
 
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Fuel capacity was increased as the Spitfire marks progressed starting at 85 gallons internal in the MKII to V then going up to 124 gallons for the MK VIII
and 160 gallons for Mk XIV. The MkVIII had quite a good range compared to the II and V so was sent for use in the far East.

The problem for escort range when compared to the Merlin Mustang is drag/boost. The lower drag and Meredith effect? of the Mustang gave it a cruise speed
around 30MPH greater than the Spitfire while using the same or less fuel. There was a proposal at one stage to shift the radiator system on the Spitfire to the
lower fuselage to give the same effect as the Mustang but the time and resources used for this would have meant the Merlin Mustang would have been in operation
first anyway.

MK XIV's were used as escort for USAAF and RAF bomber raids as far across as Switzerland with about a four hour flight time and no problem with fuel but
this still didn't match the Mustang.

A test was done earlier with drop tanks and extra fuel at Wright field in the US but to get an acceptable range with armament still onboard meant the aircraft
was over it's maximum take off weight. To get a range close to the mustang would have meant another belly tank as well putting the MK IX at 10% over it's
MTOW. The MKVIII had a stronger frame and would have been more capable but it's still pushing things.

Another option would have been to have production of the Spitfire carried out in the US as well as Britain earlier in the war. More available production would
have meant more facilities aside to do R&D giving the possibility of a longer range version in late 1942.
 
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There was a proposal at one stage to shift the radiator system on the Spitfire to the
lower fuselage to give the same effect as the Mustang but the time and resources used for this would have meant the Merlin Mustang would have been in operation
first anyway.
Not trying to design a new aeroplane either, just getting rear tanks into the Spit and into service late '42 early 43' is all I'm trying to achieve, MkIX's were already plumbed for drop tanks.
 
Again, I'll repeat why it wasn't, Charles Portal, Chief of the RAF Air Staff refused to believe that the RAF needed a fighter with that kind of range because it would be inferior to short ranged fighters, at least that was his argument.
That's the only valid argument I can see on why it wasn't done in the whole 19 page thread.
 
To fit the rear tanks that were available and in service since 1940 and later fitted to all production MkXVI's.
Varoius marks did get the rear tanks which was the main increase in fuel capacity plus bag tanks in the wings.

Nuuumannn's post is definitely relevant as it goes to the heart of the matter which was bomber doctrine.

From what I have read there was always a push pull going on as bomber proponents had been influenced by the 'bomber will always get through'
syndrome. The thing they found out was they don't all come back.

This should have been obvious from the Battle of Britain where the Luftwaffe struggled to escort bombers which were shown to be far more
vulnerable to fighter attack than thought.

When four engined bombers came around with large amounts of machine guns sticking out of them the original theory still held sway.
Again, flak and fighters with 20 and 30mm cannon literally shot that down.

Prejudice and politics does have a bad influence at times.
 
All I want is to give the Spit more endurance so it can stay in the fight, there's a reason P47's and P51's racked up big numbers of kills over Europe, they could get to the fight, the Spit couldn't, a MkIX with 300 mile radius from late 42'-early 43' would have been a handy bird.

OK, so who is going to fly the Spitfire's current missions while your long-range Spits do their new missions? Were these assets assigned to the RAF or were they USAAF fighters that would NEVER be assigned as defense of the UK? US assets were pursuing US missions, not UK missions except where they happened to coincide.

Basic question is if the SPitfires were not defending the country, who WOULD have been doing so and were they available to UK Fighter Command while the Spits were flitting about elsewhere?
 
OK, so who is going to fly the Spitfire's current missions while your long-range Spits do their new missions? Were these assets assigned to the RAF or were they USAAF fighters that would NEVER be assigned as defense of the UK? US assets were pursuing US missions, not UK missions except where they happened to coincide.

Basic question is if the SPitfires were not defending the country, who WOULD have been doing so and were they available to UK Fighter Command while the Spits were flitting about elsewhere?

I'm sure that by mid 1943 there would be enough IXs to perform escort duty and also defend the homeland.
 
I'm sure that by mid 1943 there would be enough IXs to perform escort duty and also defend the homeland.
On D-Day 6 June 1944 there were still 10 squadrons in Air Defence of Great Britain flying Spitfire Mk.V, with 8 of those belonging to 11 Group in the South East of England and 1 each in 12 & 13 Groups further north. There was even still a Hurricane II squadron based in the east of Scotland in a defensive role.

Over coming months these squadrons transitioned to a variety of types including Spitfire IX & XIV, Tempest V and Mustang III as more aircraft became available.
 
Fuel capacity was increased as the Spitfire marks progressed starting at 85 gallons internal in the MKII to V then going up to 124 gallons for the MK VIII
and 160 gallons for Mk XIV. The MkVIII had quite a good range compared to the II and V so was sent for use in the far East.

The problem for escort range when compared to the Merlin Mustang is drag/boost. The lower drag and Meredith effect? of the Mustang gave it a cruise speed
around 30MPH greater than the Spitfire while using the same or less fuel. There was a proposal at one stage to shift the radiator system on the Spitfire to the
lower fuselage to give the same effect as the Mustang but the time and resources used for this would have meant the Merlin Mustang would have been in operation
first anyway.

MK XIV's were used as escort for USAAF and RAF bomber raids as far across as Switzerland with about a four hour flight time and no problem with fuel but
this still didn't match the Mustang.

A test was done earlier with drop tanks and extra fuel at Wright field in the US but to get an acceptable range with armament still onboard meant the aircraft
was over it's maximum take off weight. To get a range close to the mustang would have meant another belly tank as well putting the MK IX at 10% over it's
MTOW. The MKVIII had a stronger frame and would have been more capable but it's still pushing things.

Another option would have been to have production of the Spitfire carried out in the US as well as Britain earlier in the war. More available production would
have meant more facilities aside to do R&D giving the possibility of a longer range version in late 1942.
Internal fuel capacity is the determinant - not external tanks. Whatever you have left after dropping externals and a.) fight for 20 in, b.) economy cruise home, c.) loiter for 30 min is central to Combat Radius estimates.

P-51B/D with fuse tank = 269gal.

Spitfire was designed to slightly lower stress limits than Mustang - at the beginning of its life cycle.

Both the wing and the cooling drag attributes contributed to superior cruise and top speed aerodynamics for the Mustang although the thin(er) wing of the Spitfire gave slightly better Cdmach profile than Mustang wing.

Changing the cooling system approach to imbedded Radiator system would have been a huge fuselage re-design (my speculation) due to differences in aft frame volumes and structure to accomodate the new Meredith type system.

Significant is he lack thereof in the later models of Spit after several years experience and knowledge of the 'do/don't do' of Mustang I and evolution of external/internal configuration changes. Even with the original allotment of NA-73/83 airframes for Merlin conversion, no attempt was made to lift the cooling system into a later model Spitfire toimprove aerodynamics. All the major changes were horsepower driven.
 
Internal fuel capacity is the determinant - not external tanks. Whatever you have left after dropping externals and a.) fight for 20 in, b.) economy cruise home, c.) loiter for 30 min is central to Combat Radius estimates.

P-51B/D with fuse tank = 269gal.

Spitfire was designed to slightly lower stress limits than Mustang - at the beginning of its life cycle.

Both the wing and the cooling drag attributes contributed to superior cruise and top speed aerodynamics for the Mustang although the thin(er) wing of the Spitfire gave slightly better Cdmach profile than Mustang wing.

Changing the cooling system approach to imbedded Radiator system would have been a huge fuselage re-design (my speculation) due to differences in aft frame volumes and structure to accomodate the new Meredith type system.

Significant is he lack thereof in the later models of Spit after several years experience and knowledge of the 'do/don't do' of Mustang I and evolution of external/internal configuration changes. Even with the original allotment of NA-73/83 airframes for Merlin conversion, no attempt was made to lift the cooling system into a later model Spitfire toimprove aerodynamics. All the major changes were horsepower driven.
Yes that is why I only referred to increases in internal fuel capacity.

The cooling system change wasn't done during the war due to time and resources and yes, a massive fuselage change. It wasn't done after the war
as the constraints changed to mostly a matter of money and an acceptance that jets would take over.
 
What new missions?, adding fuel allows the same squadrons already crossing the channel doing escort missions or sweeps more endurance, I'm not inventing a new air force.

You still don't see it, Pat.

The Spitfires were assigned short-range missions because that's what they could fly, and they did it very well. If you re-assign them to longer-range missions, then the short-range mission have to be flown by something else. If the Spitfires expend their ammunition still flying the short-range stuff, then there is no point in going on with a longer-range mission if you are largely unarmed. It is risk without potential reward. If the Spitfires hold their ammunition and bypass the short-range targets in favor of longer-range targets, then they have failed to prosecute the shorter-range missions, so somebody else has to then fly the mission objectives that were bypassed. Surely you don't think most missions were lacking an objective. The objective is the entire reason for the mission. Nobody expends fuel, aircraft wear, and potentially pilots without a clear mission objective. Training and repositioning are the exceptions to that.

What do you mean, "what new missions?"The new missions are the longer-range missions that you seem to want the Spitfires to fly and, if they did, then they would have to ignore the shorter-range missions they were actually flying in real life in order to be effective and still retain attack capability at the new longer ranges. There is no point simply flying over longer-range territory without attacking anything. The premise is simple, if they are NOT flying the missions they actually flew during the war, then who will fly them and were those assets available to RAF Fighter Command?

I'm not saying that all Spitfires expended their entire ammunition supply on short-range missions; they didn't. But a large percentage did. If they kept returning without seeing any action, then they would have been reassigned to other missions where they DID see action. Nobody keeps flying non-effective missions for too long. There is no point.

This was Europe, not the Pacific with large section of empty ocean. So, there were targets on EVERY mission and their were enemy aircraft about on most missions.
 
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Just about any fighter could use a bit more range.
Just what are you going to have to give up to get it?
An extra 20-30 gallons in a Spit might be doable, depends on the engine and tactical situation. but an extra 30 gallons is not going to get to the Ruhr and back let alone any futher.

We keep posting this picture
View attachment 665395
They built at least 40 of them, They were used by 3 different squadrons, (at the same time?)
There are performance figures for them. If you stick the tank in the rear fuselage you get rid of most of the drag but the loss of climb rate is going to be fairly close.
The idea that you can stick even more fuel inside an early Spitfire and wind up with a useful escort fighter needs some careful evaluation.

A standard ML II was supposed to climb at 2,175fpm at 20,000ft.
With the tank the climb rate dropped to 1420fpm.
Adjust for drag (about 25mph in speed) but you are not going to get most of the climb back.
For a Spitfire V fitting four 20mm guns instead of two 20s and four .30s cost just about 1 full minute to climb to 20,000ft. from a difference of about 400lbs in weight.
For these tests the Merlin 45 was running at 9lbs of boost at 2850 rpm.
Greg's you tube site has a very in depth analysis of nearly every plane that flew during the war years he often compares common pairing so you get to see graphical comparisons . Drop tanks various sizes of internal tanks and even when the super high octane gas became available as well as German use of nitrous and alcohol fuels
 

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