Qualities that made for a great aircraft that don't show up in performance stats.

michael rauls said:

I always thought the p40b and c were almost identical to p36 from the firewall back. I've sure read that a few times( yes I known that doesn't nescesarily make it true). They do sure look the same .

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And the changes to come up with Schweik's "combat variants" were the same evolutionary things (armor, self sealing tanks, etc) that would have been applied to the P-36 if it had been selected for further development.
Cheers,
Wes

XBe02Drvr said:

And the changes to come up with Schweik's "combat variants" were the same evolutionary things (armor, self sealing tanks, etc) that would have been applied to the P-36 if it had been selected for further development.
Cheers,
Wes

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Which the P-36 couldn't handle because it was barely making 300 mph with what little it had. Hence the redesign and the new version.

Look, I'm Ok with any number of you claiming that the P-36 is the same aircraft as the P-40, for whatever reason, it's just divorced from reality. I know you have some of your own little cliques in here and your own particular opinions unique to this forum, but that doesn't necessarily make it so.

Schweik said:

Which the P-36 couldn't handle because it was barely making 300 mph with what little it had.

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IIRC, the P-36 was stuck with a particularly low powered radial engine, while other round engine aircraft of about the time of P-36 - P-40 conversion were getting higher powered radials installed.
Cheers,
Wes

XBe02Drvr said:

And how! Just ask any Experimental Aircraft Association homebuilder who's tried to build a replica Spit. That ellipse is a fussbudget job to build.
Cheers,
Wes

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I believe in man hours the Spitfire wing took twice as many as the 109. Numbers matter, until the new factory opened in 1940 the Spitfire was losing the numbers game.

Schweik said:

Which the P-36 couldn't handle because it was barely making 300 mph with what little it had. Hence the redesign and the new version.

Look, I'm Ok with any number of you claiming that the P-36 is the same aircraft as the P-40, for whatever reason, it's just divorced from reality. I know you have some of your own little cliques in here and your own particular opinions unique to this forum, but that doesn't necessarily make it so.

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The reality is that, as has been stated, the XP-40 was the 10th production P-36. Yes, as development continued the wing gained weight (was beefed up) to handle the higher weights but the planform was not changed, the airfoil was not changed. Gun bays were. Yes, they did lengthen the rear fuselage of later P-40s, bu not until thousands of short fuselage P-40s were built. (and the distance between the horizontal stabilizers and the wing was changed very little, if at all)

The P-36 had about 22% more drag than an early P-40. Or perhaps it is a combination of drag and lack of exhaust thrust. Not all P-40s are quite the same either. Try taking a P-40B airframe (wing) and turning it into a P-40K capable of handling around 1500lbs high gross weight,

And how about we flip your theory/point of view?

How many 109s were there? One design that went from 1935/36 to 1945 (and beyond if we count the Spanish ones) or were there two, pre Friedrich on post Friedrich?
Or three 109s? Jumo 210 powered version, 109E and then the 109F and up? Lots of luck trying to turn a 109D into a 109G. It is going to take more than DB 605 engine, some new radiators and sheet metal.

Spitfire went through a number of wings and that was before you get to the MK 21 and up. Are they Spitfires or different designs? Vertical fins and rudders changed too.

How many changes or how big do they have to be before it is a NEW design?

So, how about some actual proof that the P-40 was a different design than the P-36/Hawk 75 and not just your opinion or the opinion of some other forum?

XBe02Drvr said:

And the changes to come up with Schweik's "combat variants" were the same evolutionary things (armor, self sealing tanks, etc) that would have been applied to the P-36 if it had been selected for further development.
Cheers,
Wes

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In your opinion would it be wrong to say that in a way they did further develop the p36 by slapping an Alison on it and giving it new nomenclature( p 40).
I've always thought of p36 to p40 as continuing development of a design much the same as the Fw 190D is still a Fw190 dispite having a very different engine.

michael rauls said:

In your opinion would it be wrong to say that in a way they did further develop the p36 by slapping an Alison on it and giving it new nomenclature( p 40).
I've always thought of p36 to p40 as continuing development of a design much the same as the Fw 190D is still a Fw190 dispite having a very different engine.

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The US had quite a few "types" that carried their own designations even though the airframe essentially remained the same, just different engines, armament or other modifications.
The P-36 is a classic case of this: YP-37, P-40 and XP-42.
P-38: XP-49.
P-39: XFL, P-400, P-63.
P-40: XP-46, XP-53, XP-60A/B/D and YP-60E.
B-17: XB-38, YB-40 and C-108.
B-24: XB-41.
B-29: XB-39, XB-44 and B-50.

There's more, but you get the idea...

The P-40 is a derivative fighter, meaning that it was created by modifying a previously existing fighter, in this case the P-36. The Hurricane is also a derivative fighter, spawning from the Fury Biplane. The disadavantage of a derivative fighter is that you may not get as good of a plane as a fresh design, think Spit and 109 here, but you can usually ramp up production very quickly, as much of the tooling and production facilities will already be in place. This is exactly the case for the P-40 and Hurricane as they were the backbone of the Allies air force for the first half of the war, when the numbers of Spitfires, P-38s ect, just weren't enough.

USAAF designations were all over the place in the late 30s and early 40s (and sometimes after that)

The original Hawk 75 factory demonstrator was rebuilt/re-engined a number of times and ended up as the XP-37


the 4th production P-36A (serial number 38-4) was completed as the XP-42 (company designation Hawk 75S)


The XP-40 had a company designation of Hawk 75P
When they substituted the Allison V-1710-33 for the Allison V-1710-19 the company changed the designation to Hawk 81.

Even Hawks with fixed landing gear kept the 75 model number although the letter designation changed with customer/engine.

All of these planes and all production P-40s used the same wingspan, the same wing area and nowhere that I have seen, is there any creditable evidence that different airfoils were used.
The often repeated claim that the XP-40Qs used a laminar flow airfoil is in dispute.

Please note that the P-39C was originally called the P-45 so changes in designation from one number to another often applied to somewhat minor changes and not new designs.

slaterat said:

The P-40 is a derivative fighter, meaning that it was created by modifying a previously existing fighter, in this case the P-36. The Hurricane is also a derivative fighter, spawning from the Fury Biplane. The disadavantage of a derivative fighter is that you may not get as good of a plane as a fresh design, think Spit and 109 here, but you can usually ramp up production very quickly, as much of the tooling and production facilities will already be in place. This is exactly the case for the P-40 and Hurricane as they were the backbone of the Allies air force for the first half of the war, when the numbers of Spitfires, P-38s ect, just weren't enough.

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P-40 was an off-spring from P-36, where early models of the P-40 shared many components & systems of the P-36, like basic fuselage, wing, control surfaces etc. Same with Bf 109E, that shared many components and systems from the Jumo-powered 109s.
On the other hand, what Fury and Hurricane basically have in common is the name of company making them - Hurricane was not just an off-spring of Fury, but a whole new aircraft.

I was thinking alot of this depends on how much change one wants to say constitutes a new design. To me a new type of engine and maybe a few minor changes to the airframe does not constitute a new design but a whole new airframe would.
Not saying this is the "proper" definition but just the way I see it.

Technically speaking, nearly half the of the US fighters in WWII were descendants of previous designs.
The P-38, P-39, P-51 and F4U are exceptions to this.

The P-40 has just been discussed at length.
The F6F came from the F4F, which came from the F3F, which came from the F2F.
The P-47 came from the P-43, which came from the P-35, which came from the SEV-3 (SEV-1XP/SEV-7).

Another good example, while not a fighter, would be the C-47, which was developed from the DC-3, which was developed from the DC-2, which was developed from the DC-1.

The "3 feet longer" part comes from the engine being longer, not the P-36 airframe being stretched. What they did was to move the firewall back so the CG would be close to the same. When I have spoken with pilots who flew both the P-36 (mid 1935) and the P-40 (mid 1938), they universally preferred the P-36 ... with the sole exception of top speed.

When you get them down to cases, it was mostly a case of how the two engines work. Radials usually cruised at low power, and the controls were light and pleasant due to being at low speeds. Most of the radial fighters in the Pacific cruised at something like 185 mph to save conserve fuel. At those speeds they handled beautifully. At combat speeds, the angular momentum of the fuselage and engine could turn (pitch) more quickly than the inline engine's longer-coupled airframe.

So, the radial P-36 was slightly more maneuverable than the inline P-40. But it wasn't by all that much. The P-40 cruised and generally flew a bit faster than the P-36, and the handling was a bit stiffer due to the speed difference. Both were very good relative to other early-to-mid 1930s US and Allied designs, but both were suffering a bit relative to the mid-to-late 1930s Bf 109 (1936) , Spitfire (1936), A6M (1939), and Ki-43 (1939). The P-36 was a product of 1933 - 1934 design and the P-40 was just a re-engine of the same airframe, with the "engineering" part of it being the powerplant, not the airframe.

From real-world events, the people at Curtiss generally pissed off Don Berlin (designer) and weren't paying much, if any, attention to fighter developments that were going on around the world. Witness the P-46 and P-53 (nothing much). The P-60 was a good-handling fighter with very-predictably mediocre speed. There wasn't a "winner" that came from Curtiss-Wright after the P-36 / P-40 series or aircraft, including their last try at it with the XF-87 Blackhawk jet. They had the much-later IBM philosophy of thinking they were the Gold standard and their thinking was "right" and everyone should just know that.

All who fail to continue to innovate will suffer the same fate with time. What is "state-of-the-art" today is outdated in 10 years. The timeframe was even shorter in the WWII fighter business. We went into WWII flying rag-wing biplanes and came out flying pressurized jets in a span of about 6 years. The P-40 was "good enough" in 1941 and was obsolete in 1944. The only bright spot in the Curtiss lineup was the XP-40Q, and it could have been a good fighter. It was a quantum leap over the P-40, to be sure, but was not a quantum leap over the then-in-service P-51. Again, Curtiss didn't look past their own lineup for a comparison standard to out-perform and, as a result, built a good-but-not-innovative offering.

About re-engined fighters in general, the P-40 wasn't the only one with radial-to-inline or vice versa. The "good" Ki-61 became the "very good" Ki-100. The "Great" Fw 190" became the "wonder plane" Ta-152. The D4Y1 and 2 became the D4Y-3 "Judy." The XB-38 ws a liquid-cooled adaption of the B-17 and the XB-39 was an inline adaption of the B-39. Both performed better than their radial-powered counterparts, but were not adopted for service. No particular point here, just saying the P-36-to-P-40 was not unusual at the time.

Oops ... double-post ...

XBe02Drvr said:

IIRC, the P-36 was stuck with a particularly low powered radial engine, while other round engine aircraft of about the time of P-36 - P-40 conversion were getting higher powered radials installed.
Cheers,
Wes

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They put in a series of radial engines in them including up to 1200 hp (though low alt rated) but it never really improved performance sufficiently for further development. That is what I mean when I say it hit a wall.

GrauGeist said:

Technically speaking, nearly half the of the US fighters in WWII were descendants of previous designs.
The P-38, P-39, P-51 and F4U are exceptions to this.

The P-40 has just been discussed at length.
The F6F came from the F4F, which came from the F3F, which came from the F2F.
The P-47 came from the P-43, which came from the P-35, which came from the SEV-3 (SEV-1XP/SEV-7).

Another good example, while not a fighter, would be the C-47, which was developed from the DC-3, which was developed from the DC-2, which was developed from the DC-1.

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This is basically my point - another classic example which I previously mentioned being Blenheim, Beaufort and Beaufighter. Blenheim and Beaufighter shared many of the same jigs and so on, but they were really quite different - night and day in terms of capabilities and versatility. Same with LaGG-3 / La 5 family.

However it is also true that sometimes within the same designation a given aircraft can change enormously. I really don't think the Fw 190D is the same aircraft as the 190A, nor the Spit XXI to the Spit I. It is somewhat subjective, which always seems to get us in trouble around here.

My point about the P-36 vs. P-40, is that the older design, the P-36, had already reached it's peak of performance before the war. It basically hit a wall both in terms of speed and carrying capacity. The difference did indeed boil down mainly to the engine but that change happened to dramatically change the aircraft.

It had a wright 1670 engine 900 hp, an early Wright 1820 Cyclone (950 hp), Pratt and Whitney 1830 Twin Wasp (900 hp, 1100 or 1200 hp depending on the subvariant), and the later model Wright Cyclone R-1820 G 205 (1200 hp) but it never made it past about 320 mph. It had a relatively slow dive acceleration though good high speed handling which showed hope for the design family so to speak. They experimented with some modern combat features like armor and heavier guns but it was limited in the weight capacity it could carry. Most were underarmed with 4 or 6 .30 caliber guns.

The P-40 started at 1000 hp (and was already 40 mph faster than the P-36) and went up to 1350 or 1500 hp (in official max boost rating) and speed went from 340 mph to 370 mph in mid 1942. By the end of 1941 variants with 6 heavy machine guns were standard.

The P-36 had 5 victory claims for the US, 269 for France (mainly in the Battle of France - with 7 aces- and another five or ten in Vichy use mainly at Morocco) and about two dozen with the RAF mainly in the CBI. Total victory claims definitely less than 300.

By contrast P-40 pilots made 2,225 victory claims for the US alone, making it the 5th ranked fighter in US use (ahead of the Wildcat and Corsair) with at least 80 USAAF Aces flying the type, it had about 130 claims for the RAAF and 100 for RNZAF just in the Pacific, and a large but unknown (to me) number by the RAF / Commonwealth in the Med where it was in heavy use for four years and was the main air superiority fighter for the most crucial period (at least several hundred claims and they had 46 Aces flying P-40s) or USSR (again, at least several hundred claims and they too had about 40 Aces flying the P-40 and multiple VVS units made 'guards' status while equipped with that aircraft). As a fighter bomber of course it also famously helped fill the CAS gap where existing Allied light, dive and medium bombers failed.

The Hawk hit a wall in terms of it's speed and carrying capacity in the 1930s. It couldn't have done what the Tomahawk and Kittyhawk did. Like the Hurricane the P-36 could survive in 1940 but would suffer in 1941 or 1942 in the same kind of areas, let alone 1943. You wouldn't be flying fighter sweeps or escort missions over enemy airfields in P-36s in 1943 I'll put it that way. They were certainly of the same DNA and very closely related, but I stand by my claim that the P-40 was a different aircraft. If we really have to I can start enumerating the specific features and design elements (Shortound already pointed out some of the changes to the wing) but ultimately it's a subjective opinion so I know some people will never change their minds on it. I doubt I will either as I've done enough research on the type to be pretty confident of my opinion on this. But I'm willing to be surprised by new evidence I hadn't considered.

Comparing the P-36's combat tally to the P-40's is not realistic.

The P-36 in U.S. service saw combat against enemy elements only once: 7 December 1941, and in that battle, the P-36 drew first blood, downing two A6Ms by American pilots who not only had no previous combat experiance, but were wearing pajamas.

GrauGeist said:

Comparing the P-36's combat tally to the P-40's is not realistic.

The P-36 in U.S. service saw combat against enemy elements only once: 7 December 1941, and in that battle, the P-36 drew first blood, downing two A6Ms by American pilots who not only had no previous combat experience, but were wearing pajamas.

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It's a fair point - the record of the plane in the Battle of France was certainly good, but they were still available to the RAF / Commonwealth in some quantity (about 200 initially then as many as 500 by around 1942, partly from license production in China and India) in 1940 - 43, but they were consigned to Tertiary Theaters (basically India) where they saw little combat. The US had some (I think about 150) too - and needed fighters, but kept them out of the combat zones.

I think I left out the Finns who had some (as they did with nearly every interesting early war fighter) about 40 of them with which they scored 190 claims. They liked it but they marked it as too slow. Still I'll admit those 190 claims bumps it up to close to 500 victory claims in the war which is pretty decent for an obsolescent plane.

To be honest I suspect the P-36 would have probably been more useful in the Pacific than the F2A or P-400s they did send, but I do also think it had already reached it's limit and they were right to save the freighter space for the P-40s and later eventually, P-38s, P-47s etc. They did well at Pearl Harbor admittedly but I think P-36 pilots would have trouble with Zeros in 1942 or later. And I don't think the P-36 could have held it's own in the Med against Bf 109Fs in 1941 or 1942, let alone 109Gs.

Isnt part of this company marketing, they want to continue association with a successful line and forget about the clunkers?

My great-Uncle, who missed making history because his P-36 had no ammunition that morning, insisted that he would have happily flown the P-36 into battle instead of the P-39 (which he hated with a passion) or his P-38.
He and other pilots liked the P-36's handling and performance - it's only shortcomings were it's light armament and lack of armor and self sealing tanks.
Bottom line, is that it was a magnificent fighter for it's time, but that time had come and gone, as with most things.