XP-40Q: what was it able to do when?

Although we could agree or disagree or walk away with our own therories on this, this thread is most interesting!!!

While this thread certainly indicates that NAA didn't use any of the Curtiss data for the Na-73, I have heard from at least two people who claim otherwise. One was there at the time and the other is the son of the designer of the P-40. There is no proof of their claims that I have yet uncovered, just their claims that are , so far, unsubstantiated.

As to the XP-40Q before 1943, I heard the study was done early-on and was not called the "XP-40Q," but was rather a study for a general airframe drag cleanup of the P-40 (which hopefully we all agree it could have used), and that much of the "cleanup" was later incorporated into what later became the XP-40Q. If people think Curtiss "sat on" a cleanup, please remember that during the war the Government didn't care what you wanted to improve … you had to fulfill the contract that was signed. So if Curtiss had a contract for, say, X number of P-40B/C's, that's what they had to deliver. If the prime customer isn't really interested in your hot new development, you really have nowhere to go with it.

It may well be that the general cleanup was, in fact, the XP-46 and NAA never used that info on an aircraft design that came from NAA. I agree this appears to be the case at this time. However, the XP-40Q did wander into laminar-flow wings, at least according to my sources (including Vee's for Victory, among others), and was pretty decent aircraft in 1943. The fact remains the XP-40Q wasn't selected for production and the P-51 was. Pretty much end of story, at least for the P-40 developments. The XP-4Q was the last attempt to make the basic P-40 into a much better aircraft.

So I must agree with Drgondog that there appears to be no objective evidence at this time of the Curtiss data being used early enough to have had an impact on the Na-73.

The bubble canopy thing: it appears to me that the British first used the bubble canopy on the Miles M.20 (first flight: Sep 1940) , I believe, and that everyone else liked the idea. Again, I wasn't there and can't make any definite statements, but it appears the Mustang bubble canopy development was underway when the Typhoon was converted to bubble canopy.

Timeline:
2/27/1943: Two P-51 airframes are released from Land Lease contract for bubble canopy development (43-12102 was one).
May 1943: Production of Allison-engined Mustangs comes to an end.
7/21/1943: Contract signed for 2,500 P-51D's with bubble canopy.
August 1943: Hawker converts a Typhoon to bubble canopy and everyone likes it. Soon is standard.
Sumer 1943: Republic converts the P-47 to bubble canopy.

Since the Typhoon was made in Great Britain, it could easily be the first bubble canopy deployed into service since "service" was only a short hop away. Anything from the U.S.A. would have to be made, accepted, and shipped overseas to get deployed. Of course, "in service" could also mean in the USAAC inside the U.S.A. … I suppose. It appears to have all happened in 1943.

So, I now wonder who was really first with the all-round vision bubble canopy in a deployed fighter aircraft. Popular history has it as the British, but perhaps some research is indicated on this when I get the time and inclination … until I do, I'll assume it was the British.

GregP said:

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However, the XP-40Q did wander into laminar-flow wings, at least according to my sources (including Vee's for Victory, among others),
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Mr. Whitney got this one wrong?
He does say that "XP-40Q had been modernized by giving it laminar flow wing", pg. 184 (it does not have a referrence there, unlike most of the sentences), however at next two pages he lists the exissting airframes that received different engines, canopies, different oil cooling arrangement, and, most importantly, when the wing was clipped (why? if the new wing is of laminar flow). Further, the U/C still retracts in the P-36 style, the armament is reduced because of oil radiators, nobody ever saw any increase in fuel supply - the wing of the XP-40Q has "P-40" written all over it.

About the shape, I agree ... pure P-40, but I've heard before that at least one of the XP-40Q's had a liminar flow wing. That was many years ago at an aishow inA rizona when we still had quite a number of former WII pilots around. Airtfoil sections do not dictate wing shape from above. You can make an airfoil into almost any shape.

What objective proof do you have the Dan Whitney was wrong? Any design documents from the completed project?

What objective proof do you have the Dan Whitney was wrong?

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I have his own words: all the XP-40Qs were once stock airframes, and changes listed (when those stock airframes became XP-40Q) do not count the laminar flow wing at any time. Mr Whitney, again, does not give a reference to the claim XP-40 have had laminar flow wing - you can note that he gives references for almost every second sentence.

I suppose we are interpreting things differently. Since so little is available on it, I say it makes no difference in the long run, the XP-40Q was not selected for production, so it doesn't matter. You could be right or not. With only 3 airframes contstructed, it is a footnote in history at best that never went anywhere.

I'll ask Dan next time I see him, which will probably be our next airshow in May. Usually we have lunch at least once.

Westland Whirlwind had what was effectively a bubble canopy and first flew late 1938.

Yep, it did. Thanks. I'd say it was before the Miles M.20 ... but it DID have canopy frames and was not a one-piece unit as far as I know. I could be wrong here.