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

[tomo pauk]

In order the discussion about the XP-40Q does not clog the thread about the P-39, Ive started this thread.
Sometimes in the forum, and on another places, it is stated that it was pity that XP-40Q was not produced used in ww2, beacause of it's great combat capabilities. I disagree with that, my argument being the plane needed too much of engine power to really perform as good as it's contemporaries, while not offering any combat range and punch wanted by it's most likely costumer (USAF).

By GregP:

Hey guys, I know what I have heard. You don't have to agree. Nobody in 1940 did an airplane in 120 days; it took years.

Maybe NAA was a competent company?

General Davy Allison (no relation to the engine company), who demonstrated the P-40B/C to Chenault, stated that North American had the XP-40Q plans before they designed the XP-51 (or NA-73). He visited our airshow and the shop and, yes, we let him start our run engine on the stand. He loved it and told some stories. I don't disbelieve him. The preliminary drawings were available well before 1942, especially to the designers and the USAAC, who believed they owned them since they were the customer.

It would be much easier to discuss the technicalities without the red line of 'USAAC owned this or that' or 'we run Allisons just fine'.
So the General demonstrated the P-40s to Chenault, and that makes him a procurement specialist that knows XP-40Q plans were shipped to NAA? That's as believable as the talk the British fuel was the culprit for P-38 troubles.
The XP-40Q featured bubble canopy, the NAA-73 did not. The 2-stage engine was in Q (thinkered about in 1940???), single stage in NAA-73. The Q have had the P-36/-40 legacy, 5 spar wing, the U/C retracting ackward, unlike the NAA-73. The cooling systems were way too different. Fuselage was also a carry on from P-36/-40.

Heck, the DOD just recently sent Boeing and Lockhhed-Martin each other's porposals for the new tanker to the wrong companies! Anybody remember that? And that was pure horsecrap; they fostered competition. Anybody who believes that was a mistake is in never-never land. ... and Japan is now flying the Boeing tanker while we still aren't.

Why should we believe that current US procurement is other than a pale shade of ww2 procurement? Let alone that it has to do anything with ww2.

Sure, it was all a nice, 120-day development ... interesting it was never repeated, isn't it, even in the face of wartime necessity? How long did the P-47 take? Or the F4U Corsair? Or the P-39 or P-63? Or even the Curtiss-Wright CW-21? Or the P-61?

Don't think the Bell or Curtiss can hope to match with NAA. The P-47 and P-61 were far more complicated things to pull out than a simple single engined fighter.

Your opinion may vary, and that's OK with me. Maybe there wasn't any Kennedy conspiracy either. Only one guy who could put two bullets into close targets at 120+ yards in only a couple of seconds with an old beater Russian gun that can't DO that in anybody else's hands including a head shot? I'm not that much of a believer ...

Opinions are one thing. Another thing are facts. So how really good was the Q; when it was bee able to do what is advertised; how much of improvement it was vs. contemporaries; why would the perceived customer buy it?

 

[Aozora]

Two things:
1) Is there any reason to believe that the P-51 was designed entirely from scratch from the time the design was first mooted to the British? It is entirely possible that Edgar Schmued and co already had some preliminary concepts taking shape well before the Brits came along and asked NAA to build P-40s, which is why they were able to propose a new design. Has anyone got this book (Mustang Designer) which might help?

2) Is there any more concrete evidence, and, with respect to GregP what he says is still hearsay, that the XP-40Q was the inspiration for the P-51, rather than the XP-46? The timelines are very strange, because the XP-46 first flew four months after the NA-73X

(This from Curtiss Aircraft 1907-1947, Peter M Bowers)

XP-46-The first XP-46, Army serial 40-3053, made its first flight on 15 February, 1941. It bore a general resemblance to the P-40 but was smaller
and featured an inward-retracting undercarriage. Armour and fuel tank protection were improved and the armament was increased to two '50calibre
machine-guns in the nose below the cylinder banks and four '30calibre machine-guns in each wing, making it the most heavily-armed US fighter up to that time. Powerplant was the 1,150 hp Allison V-1710-39. Automatic leading-edge slats were installed on the outer portions of the
wing.
XP-46A-To save time, the second XP-46, 40-3054, was delivered without armament or radio for aerodynamic testing and was redesignated XP-46A. The XP-46s had no significant advantage over the P-40 except in firepower and the design was not developed further. (page 435)

The basic design and disposition of the armament of the XP-46 were a lot more similar to the NA-73X than the armament and layout of the XP-40Qs, plus, AFAIK the original XP-40Qs were derived from P-40Ks and a P-40N, and first flew in 1943(?):

Two P-40Ks (42-9987, 42-45722) and one P-40 (43-24571), were extensively modified with revised cooling systems, two-stage superchargers, and structural changes that altered their appearance. When coolant radiators were moved into the wing roots, the two inboard guns were removed.
The most prominent XP-40Q feature, used on 42-45722 and 43-24571, was the addition of a bubble canopy as on the 'XP-40N'. Later, the wingtips were clipped. Speed increased to 422 mph (679·13 km/h) at 20,500 ft (6,248 m) making it the fastest of all the P-40s. Registered NX300B, the second XP-40Q was an unauthorized starter in the 1947 Thompson Trophy; it was in fourth place when it caught fire. (492)

What is really interesting is that Curtiss tested an XP-60 with Merlin engine and laminar flow wings in 1941 - was this the aircraft Gen Davy Allison was describing?

XP-60 (Model 90, 90A)-One XP-60, Army serial 41-19508, was ordered on I October, 1940. This used a P-40D fuselage and tail assembly fitted with
a new wing that featured a laminar-flow aerofoil and inward-retracting undercarriage. The powerplant was the 1,300 hp Packard-built Rolls-Royce V-1650-1 Merlin as used in the XP-40F then under development. The firepower increase over the P-40 was impressive-eight '50-in calibre machine-guns in the thick-section wings. Armour protection was provided for the pilot and the fuel tanks were self-sealing.
After test flights began on 18 September, 1941, it was found necessary to enlarge the vertical tail and make minor modifications that resulted in redesignation as Curtiss Model 90A. The XP-60 was later redesignated XP-60D. (437)

 

[tomo pauk]

Thanks for the feedback, Aozora. I could not agree more about the likely existence of a concept in NAA egineering staff prior the British approached them.

There was one thing NAA got from Curtiss, for 56,000 $: the data about the XP-46 (mentioned at book Vee's for victory, attributed to Kelsey). Now before people start claiming that Curtiss actually designed future P-51, we can take a look at what XP-46 was able to do. That would be 355 mph (unarmed, almost unpainted), way under what (X)P-51 was capable for, despite it's bigger wing weight. NAA installed a much more refined belly radiator, laminar-flow wing, wheel well covers, along with other, less visible things, making their product excellent.

Two P-40Ks (42-9987, 42-45722) and one P-40 (43-24571), were extensively modified with revised cooling systems, two-stage superchargers, and structural changes that altered their appearance. When coolant radiators were moved into the wing roots, the two inboard guns were removed.
The most prominent XP-40Q feature, used on 42-45722 and 43-24571, was the addition of a bubble canopy as on the 'XP-40N'. Later, the wingtips were clipped. Speed increased to 422 mph (679·13 km/h) at 20,500 ft (6,248 m) making it the fastest of all the P-40s. Registered NX300B, the second XP-40Q was an unauthorized starter in the 1947 Thompson Trophy; it was in fourth place when it caught fire. (492)

Some things are omitted in the excerpt.
There were three subtypes of the Q line:
-latest (Q-3), converted from P-40N AC43-254571, clipped wings, the one capable for 422 mph, using the F-28R engine (1700 HP @ 3200 rpm @ 26000 ft, WER 'wet'; military rating: 1100 HP @ 3200 rpm @ 28000 ft), shipped to USAF for testing in 'early 1945'
-Q-2, converted from P-40K AC42-45722, featuring the F-27 engine ( 1500 HP @ 3200 rpm @ 6000 ft, yes, 6000 ft, WER 'dry'; military rating 1150 HP @ 3000 rpm @ 22400 ft), clipped wings, bubble canopy, revised cooling system (the Q-3 also featured these 3 modifications). No firm date of delivery or/and tests, no known performance either.
-Q-1, conversion of P-40K AC 42-9987, the F-20R engine (single stage) initially, later the F-27R, without modifications of the wing, canopy cooling system layout. Also no know firm date of delivery testing.

data from 'Vee's for victory'

During January of 1944, 'one of the XP-40Q was flow to Eglin Field' (ie. test facility), the aux supercharger ratio of the F-27R engine changed from to 7,23:1, ie same as F-28R. Without ADI, it still cannot beat a fully fledged F-28R.
Unfortunately, despite stating the legacy P-40 airframes the Qs inherited, Vee's claim (non-referenced) that the laminar flow wing was installed. A quick look at speed vs. HP needed for the speed quickly disproves that claim - both P-51 and P-63 needed far less power to achieve better speeds, despite having larger wings.

 

[wuzak]

The XP-46 was ordered in 1939.

The P-40 model in production at the time of the British Purchasing Committee signing with NAA was the P-40C, maybe even B.
The one on the drawing board of Curtiss would have been the P-40D, whose improved performance was the reason that the XP-46 progressed no further.

The order for the XP-53 prototypes was signed on 1 October 1940, less than a month before the NA-73 flew. The XP-53 was the first of the Curtiss fighters to have a laminar flow wing. This was to be powered by the Continental IV-1430. Since that engine program was lagging behind, the XP-53 was dropped, and the XP-60 with Merlin 28 (in lieu of V-1650-1) was given the go-ahead.

From Joe Baugher:

Another urban legend surrounding the Mustang is that it owed a great deal to the Curtiss XP-46 and, in fact, stole numerous design features from that fighter. It is true that the British had insisted that since NAA had no fighter experience they should secure all current data from Curtiss about both the P-40 and the XP-46. Although NAA did pay $56,000 to Curtiss for technical aerodynamic data on the XP-46, there was only a very broad resemblance between the XP-46 and the NA-73X. The Curtiss aircraft shared only a similar radiator/ oil-cooler configuration with the NA-73X, and did not have laminar flow wings. In point of fact, the development of the XP-46 lagged behind that of the NA-73X, and prototypes were not ready for flight until February of 1941. In addition, preliminary design of the NA-73X was completed before NAA gained access to the Curtiss material. It could even be argued that the XP-46 data was most useful to NAA in guiding them in what NOT to do. The NA-73X appears to owe virtually nothing to any previous fighter design. Nevertheless, despite convincing denials from both Edgar Schmued and aerodynamicist Edward Horkey, the full magnitude of the contribution of Curtiss to the NA-73X design remains controversial to this day.

North American NA-73

There seems little doubt that NAA had dabbled in the design of a fighter before the NA-73 order. So it would seem they at leas had a head start.

Regarding the XP-60:

The performance of the XP-60 was disappointing as well, with a top speed of only 387 mph at 22,000 feet. It took 7.3 minutes to reach an altitude of 15,000 feet, and service ceiling of 29,000 feet. Some of the reason for the disappointing performance was due to the wing surface not being finished to the degree of smoothness required for the laminar flow wing. Another factor was the fact that the Merlin engine did not deliver the guaranteed output.

Curtiss P-60

I thik it was mentioned in Vees for Victory that Curtiss had quality control issues when they were building P-47s later in teh war. Perhaps the wing smoothess issue was an early sign of their quality problem?

 

[wuzak]

The Xp-53/XP-60 looked quite good in its Merlin form

http://upload.wikimedia.org/wikiped...ht_(from_XP-53_design)_061024-F-1234P-013.jpg
http://www.aer.ita.br/~bmattos/mundo/images_jul06/curtiss_p60-3.jpg

The XP-60A with V-1710 and GE B-series turbo not so much.
http://www.nationalmuseum.af.mil/shared/media/photodb/web/061024-F-1234P-016.jpg

Though it did perform well, its orders were cancelled after Pearl Harbour to concentrate on production of existing types.

Here's the XP-46
http://i987.photobucket.com/albums/ae351/markdd/XP-46-_zps3207e1c4.jpg

 

[wuzak]

I wonder if the XP-40Q's low performance for power was partly due to the leading edge (sort of) radiators?

They do seem small compared to the Tempest I
http://upload.wikimedia.org/wikipedia/en/9/9f/Hawker_Tempest_I_HM599.jpg

And Fairey Firefly
http://www.richard-seaman.com/Aircraft/AirShows/Nellis2004/Highlights/FireflyBankingLeft.jpg

Albeit being used with a less powerful engine.

 

[Shortround6]

Picture of FIRST P-40Q.

Please notice the startling resemblance to the P-51............

An Earlier P-40 with "wing" radiators.

Original P-40 Prototype, Plane was faster with Chin Radiator;

Also a P-40F with modified radiator.

Curtiss seems to have had quite a bit trouble figuring out where they were hiding the plans for the P-40Q.

 

[tomo pauk]

I wonder if the XP-40Q's low performance for power was partly due to the leading edge (sort of) radiators?

They do seem small compared to the Tempest I
http://upload.wikimedia.org/wikipedia/en/9/9f/Hawker_Tempest_I_HM599.jpg

And Fairey Firefly
http://www.richard-seaman.com/Aircraft/AirShows/Nellis2004/Highlights/FireflyBankingLeft.jpg

Albeit being used with a less powerful engine.

The leading edge radiators were just the oil coolers, Prestone cooler was under the chin. Tempest I have had both oil Prestone radiators at the leading edge, so was the intercooler of Firefly.
The engine performance was exceptional, if we talk about F-28R, but the engine was too late to matter for ww2.

Simply got to say this: Tempest I, what a looker.

 

[drgondog]

The Brit Procurement team signed the agreement for the preliminary design of NA-73X, Lee Atwwod's team completed the 3D Pre Design with weights and lines prior to the contract to proceed on May 4. The Brits insisted on a parallel effort to engage Curtis for the P-40 production. Curtiss was contacted on May 4th and the discussions concluded with an agreement between the NAA and Curtis for P-40 data data on wind tunnel data including cooling and drag results of the XP-40.

Note: the XP-46 was entering mock up stage and had no test data whatsoever at the time NAA took delivery of the XP-40 data. The USAAF ordered two XP-46 prototypes in December 1939, and the first Army inspection of the XP-46 occurred on March 4, 1940.

Dutch Kindleberger ordered Schmued in very late March to prepare 3 View side elevations with weights and balances, specs, performance estimates around an In-line engine with 4x20mm plus some detail about the armament inst'l. These few drawings were in Kindleberger's hands when he went to UK to negotiate with Sir Henry Self. Self signed the PO for 400 NA-50B to NAA Spec 1592 on April 11. Schmeud started on a mock up just prior to the April 11 contract award and completed it in 3 days using plaster of paris, paper mache and plywood. (pages 51-54 Mustang Designer). The NA-50B became the NAA 73 on April 24 for the construction of one "Allison engined pursuit".

The entire Curtiss connection was at the direction of Kindleberger so that he could tell the Brits that NAA was utilizing P-40 experience in the development.

Schmued corrected Lee Atwood's recollection that the radiator design was spawned by Curtiss, noting that Raymond Rice (Chief NAA Engineer and recipient of the box of Curtiss data) was completely dis-connected from the P-51 project led by Schmeud and that the Curtiss data was Not used in the design of the P-51.

It's pretty simple really. One Curtiss had no idea how the design progressed, or how the data was used. Two, Both Ed Horkey (aero) and Schmeud (structures and P-51 Program manager) state unequivocally that nothing from the XP-46 was used, Horkey stating that the Xp-46 data was rehashed P-40, and that the 3 view drawings and mock up were complete before Atwood went to Curtiss two weeks later. Three, neither were sure that any data related to the XP-46 was ever examined at NAA. Four - all the sketches and 3 View and Mock Up were complete weeks before Atwood went to Buffalo to arrange the purchase of the data.

Conclusion - The NA-73 was not not connected to the XP-46 in any way.

Last. The NA 73 first flew on October 26 but the airframe was 100% complete on September 9, 1940. Greg may be under an impression that it was 'two years' or even 'one year' but the actual date from the April 24 Contract, which is earliest time that a full team could be named for the detail design, to October 26 is six months to first flight and four months to completion of the XP-51 airframe. If you measure from the time a paper napkin sketch flowed into the start of a serious three view drawing Kindleberger could show Sir Henry Self - then you have seven months.

Most folks would think that is pretty good even if '100' days is off.

 

[MikeGazdik]

I don't have all the records to look back on. But If you look at the T6 Texan / Harvard, I think its obvious that it is "related" to the Mustang. Particularly in the wing. Much like you can see the design genesis in the P-35 / P-43 from Seversky to the P-47 Thunderbolt.

So is it you can see Curtiss when you look at any of the P-40 series including the X-planes. I think it even extends to the Helldiver and the C-46.

 

[GregP]

Let's say Drgondog and I have heard different stories from people invlolved ... unless he is using reference material and not direct communication to make his post. I don't know and decline to ask. Either one of us or neither could be correct, it depends on who you speak with and what their recollections are ... and the real facts .. which are probably lost to time or are hideen away in files buried somewhere that are unavialble to the causal information searcher.

I KNOW what history records (no evidence of collusion with the XP-40Q plans), but that doesn't make it either true or false, just what has been accepted. The world was also accepted as flat right up until it wasn't. Most criminals deny they did the crime right up until and sometimes even after they are convicted. NAA would never admit if they DID use the Curtiss Data including the XP-40Q initial plans, and Curtiss hasn't "sued" over it, but that doesn't weigh in with me at all either way.

Personally I don't care, but I do WONDER after hearing what we heard. I'll not get in line and accept the word of a rival that he didn't use preliminary design data from a competitor. I bet that never happend in automotive Formula 1, either, huh? Especially ot a "front runner' like McClaren? Oh wait ... it DID about 3 years ago and they are still under suspension ... maybe they are back this coming year ...

Back in 1940, the ability to feret out the truth may well have been much harder than it is today, given the lack of a world wide web that can record everything and electronic copies of communications, etc. ... maybe not. Either way, I still wonder and have simply stated that plus what was said in paraphrase. Nodoby else need consider it, believe it, or think it has merit. It wasn't my own concoction to start with and I probably should not have even mentioned what was said. Certainly, if the proof is there and still exists, somebody would have to believe it, and then take the trouble to dig it up and publish it.

With the posts above, even fans of the time are not inclined to pursue it, much less someone who is NOT a fan. Neither am I at this time.

Doubting posts are not an opinion changer and people who don't consider alernatives are usually "mind made up" and cannot be swayed either way, even in the face of facts, which I don't pretend to have established ... I just passed on what I heard.

Neither am I a follower who blindly accepts the published version of "facts." Indistrial intrigue in the face of huge wartime profits was a fact, not heresay. Whether or not this subject was a part of that is in some doubt ... by me at least. No conviction is likey at this extended time past the deeds or lack thereof.

So, let's get back to the XP40Q (thread subject) and let this one drop. Argument about it is fraught with peorsonal opinion.

From what I have read, the XP-40Q seems to have been a good fighter with characteristics that made it good ... but it fell slightly short in top speed to the P-51 (422 vs. 437 mph). Why that small difference would be important is beyond me since neither was likely to attain max speed except in a slight dive anyway.

So I ask myself if the XP-40Q, in 1943, would be an asset at the time it was developed..

The answer is yes, if the logistics chain could be justified. Since we were able to produce enough P-51's to meet war needs in the actual event, the obvious answer is that another long, complicated logistics chain with mechanics, spare parts, etc. was probably not justified once the P-51 logistics chain was in operation. It would have been cheaper and more efficient to expand the P-51 chain than to establish a new one to support planes that could be supported by the P-51 production line instead.

Logically then, what happened was probably the better choice, even if the XP-40Q could have been a good addition, which I believe it could have been in other circumstances. Since I am a fan of obscure types, the XP-40Q simply falls in there with other potentially good or great planes that came at just the wrong time or just at the time when circumstances dictated another choice, through no fault of the particular prototype under consideration.

So, though I lament the choice to not build the P-40Q, it was probably the right choice at the time. Curtiss did not long survive in the airframe game after the P-40 anyway, and the P-40Q might simply have prolonged the agony a bit longer.

Long live the P-51 and I wish an XP-40Q survived for at least museum flights.

 

[wuzak]

I bet that never happend in automotive Formula 1, either, huh? Especially ot a "front runner' like McClaren? Oh wait ... it DID about 3 years ago and they are still under suspension ... maybe they are back this coming year ...

It was 2007. McLaren weren't suspended, but were fined $100m and excluded from the constructor's championship, but not the driver's championship, their drivers finishing equal second by one point. They won the driver's championship (Hamilton) literally at the last corner of the last lap of the last race, and finished second to Ferrari in the constructor's champiosnhip.

 

[tomo pauk]

<snip>

So, let's get back to the XP40Q (thread subject) and let this one drop. Argument about it is fraught with peorsonal opinion.

From what I have read, the XP-40Q seems to have been a good fighter with characteristics that made it good ... but it fell slightly short in top speed to the P-51 (422 vs. 437 mph). Why that small difference would be important is beyond me since neither was likely to attain max speed except in a slight dive anyway.

So I ask myself if the XP-40Q, in 1943, would be an asset at the time it was developed..

Sorry, Gerg, but it seems to me that you're comparing an early 1945 plane (XP-40Q-3) with mid 1943 plane (Merlin Mustang). That is what makes the whole difference, not 15 mph. Let alone the far better combat range, plus, by mid 1944, 50% more firepower, and no problems when in high speed dive.
Neither the XP-40Q-1, nor XP-40Q-2, and those are still later designs than P-51B, did not have the horse power to attain the much advertised 422 mph, not until they receive the F-28R engine. A plane that can do 422 mph, with short range, in 1945, was NOT like something the AAF was after.
If AAF was really into a 420 mph, short range airplanes, they could have had the P-63A in service in early 1944 (more than a year before the serial produced P-40Q), looks to me that was not the case.

The answer is yes, if the logistics chain could be justified. Since we were able to produce enough P-51's to meet war needs in the actual event, the obvious answer is that another long, complicated logistics chain with mechanics, spare parts, etc. was probably not justified once the P-51 logistics chain was in operation. It would have been cheaper and more efficient to expand the P-51 chain than to establish a new one to support planes that could be supported by the P-51 production line instead.

If we really want an over-performer, produced by Curtiss, they can start to produce the P-47G (but in a proper way, not lame as they did historically), for which they have had the contract signed in June 1942. The logistic chain was there, in all war theaters USAF was fighting. The P-47 did have better range, twice the firepower, and, by 1945, it was circa 50 miles faster - in service vs. a prototype to boot.

Logically then, what happened was probably the better choice, even if the XP-40Q could have been a good addition, which I believe it could have been in other circumstances. Since I am a fan of obscure types, the XP-40Q simply falls in there with other potentially good or great planes that came at just the wrong time or just at the time when circumstances dictated another choice, through no fault of the particular prototype under consideration.

Wrong time, indeed. Too late.

So, though I lament the choice to not build the P-40Q, it was probably the right choice at the time. Curtiss did not long survive in the airframe game after the P-40 anyway, and the P-40Q might simply have prolonged the agony a bit longer.

Right choice, indeed. Curtiss-Wright also dissapeared as an engine maker.

Long live the P-51 and I wish an XP-40Q survived for at least museum flights.

Agreed.

 

[drgondog]

Let's say Drgondog and I have heard different stories from people invlolved ... unless he is using reference material and not direct communication to make his post. I don't know and decline to ask. Either one of us or neither could be correct, it depends on who you speak with and what their recollections are ... and the real facts .. which are probably lost to time or are hideen away in files buried somewhere that are unavialble to the causal information searcher.

When Al White and Jim Brooks were at North American Aviation I did meet Horkey but we talked only about the evolution of the P-51 not the 'box of data'. Having said that, reference and cross reference documentation as well as documented dialogue and debate are usually better references than 90 year old memories of persons not part of the inner workings of Curtiss or North American Aviation. Neither White nor Brooks ca 1960-61 had any part of the design but Horkey was the driver behind the lines and the lower cowl design and the NAA Laminar flow wing.

I KNOW what history records (no evidence of collusion with the XP-40Q plans), but that doesn't make it either true or false, just what has been accepted.

What makes it 'false' is that the P-40Q was a P-40K-C10, yanked off the production line Dec 43/Jan 43...in other words, absent "Back to the Future" time travel the assumption of a connection is foolish on the face of the facts.

The world was also accepted as flat right up until it wasn't. Most criminals deny they did the crime right up until and sometimes even after they are convicted. NAA would never admit if they DID use the Curtiss Data including the XP-40Q initial plans, and Curtiss hasn't "sued" over it, but that doesn't weigh in with me at all either way.

It is pretty simple Greg. NAA payed $50,000 for access to the XP-40 data that Curtiss provided. The notion of the use of the XP-40Q data before there was XP-46 completion of mock up is a novel claim. Did you at any time know enough of the timeline to question your source? Have you a source from the Curtiss design team that thinks there is any connection?

Personally I don't care, but I do WONDER after hearing what we heard.

I suspect We think you were snowed... and having not cross referenced the timelines You believed what you were told.

Back in 1940, the ability to feret out the truth may well have been much harder than it is today, given the lack of a world wide web that can record everything and electronic copies of communications, etc. ... maybe not. Either way, I still wonder and have simply stated that plus what was said in paraphrase. Nodoby else need consider it, believe it, or think it has merit. It wasn't my own concoction to start with and I probably should not have even mentioned what was said. Certainly, if the proof is there and still exists, somebody would have to believe it, and then take the trouble to dig it up and publish it.

Now that you have access to the internet, the books published by authors 'who were there' and part of the design teams, what is your timeline for the Preliminary design of the XP-40Q? And perhaps you can trace the completion of the XP-46 Mock up in March 1944 with lines and profiles of the NA-73 started in late March before NAA contacted Curtiss to purchase XP-40 wind tunnel data? Then perhaps cite the design milestones for lower cowl/radiator design for NA-73 during late March through April 11, 1940 when Kindlebeger completed his presentation of Schmued's 3-view?

Greg - Aprill 11, 1940 is three years before work was fully in progress on the XP-40Q. As to the XP-46 which design features do you believe were 'stolen' by NAA before NAA received the Purchased XP-40 data three to four weeks after the completion of the NA-73 drawings were presented to Lord Self, discussed and contract executed on April 11?

With the posts above, even fans of the time are not inclined to pursue it, much less someone who is NOT a fan. Neither am I at this time.

Doubting posts are not an opinion changer and people who don't consider alernatives are usually "mind made up" and cannot be swayed either way, even in the face of facts, which I don't pretend to have established ... I just passed on what I heard.

Neither am I a follower who blindly accepts the published version of "facts." Indistrial intrigue in the face of huge wartime profits was a fact, not heresay. Whether or not this subject was a part of that is in some doubt ... by me at least. No conviction is likey at this extended time past the deeds or lack thereof.

Not being a follower is healthy - especially when you have a series of facts that are contrary to the 'leader's story'.

So, let's get back to the XP40Q (thread subject) and let this one drop. Argument about it is fraught with peorsonal opinion

Greg - so far you haven't presented what you believe to be facts and pointed to the source(s) that you believe provide substantive facts. If you have something worth presenting that proves that a.) XP-46 wind tunnel tests were completed, and presented to NAA for $50,000 or b.) stolen by NAA, or c.) that the XP-40Q preliminary design was completed prior to March 1940 - trot 'em out. As the three XP-40Q's were P-40K and P-40N and the earliest of the three came off the assembly line in December 1942 - it would seem that work on the XP-40Q started about two years after NAA purchased XP-40 data on or about April 30-May, 5 1940? Ditto the Allison 1710-121..

From what I have read, the XP-40Q seems to have been a good fighter with characteristics that made it good ... but it fell slightly short in top speed to the P-51 (422 vs. 437 mph). Why that small difference would be important is beyond me since neither was likely to attain max speed except in a slight dive anyway.

15mph is huge - airframe to airframe. And 437mph for all the P-51D's with 1650-7's were with full combat load - w/o external tanks.



So I ask myself if the XP-40Q, in 1943, would be an asset at the time it was developed..

Since it didn't start as a prototype until mid 1943, it was hardly developed to fly by late 1943 and projected less performance that the P-51B-1 rolling off the assembly lines when the XP-40Q/P-40K airframe was pulled from the production line.

The answer is yes, if the logistics chain could be justified. Since we were able to produce enough P-51's to meet war needs in the actual event, the obvious answer is that another long, complicated logistics chain with mechanics, spare parts, etc. was probably not justified once the P-51 logistics chain was in operation. It would have been cheaper and more efficient to expand the P-51 chain than to establish a new one to support planes that could be supported by the P-51 production line instead.

Logically then, what happened was probably the better choice, even if the XP-40Q could have been a good addition, which I believe it could have been in other circumstances. Since I am a fan of obscure types, the XP-40Q simply falls in there with other potentially good or great planes that came at just the wrong time or just at the time when circumstances dictated another choice, through no fault of the particular prototype under consideration.

So, though I lament the choice to not build the P-40Q, it was probably the right choice at the time. Curtiss did not long survive in the airframe game after the P-40 anyway, and the P-40Q might simply have prolonged the agony a bit longer.

Long live the P-51 and I wish an XP-40Q survived for at least museum flights.

I wish a lot of the X frames were still around.

 

[GregP]

Drgondog,

I know the history of the XP-4Q airframes. What I'm talking about is the idea for the design that was originally put on paper. I have heard the design was drawn up in early 1940, but there were other priorities at the time for Curtiss. Since I wasn't around, I cannot either confirm or deny this and I suspect that none of us in here can. Naturally, the USAAC felt they owned the designs since they were the customer for the P-40.

While the design may or may not have been the government's to show to a competitor, Curtiss may have had little practical shoice since teyw ere dependent upon the government for survival.

I posted what I heard. I do not claim that it was absolutely so, I passed on what I heard. If you had been there, you'd have heard it, too and would be free to make your own arguments or conclusions after the fact.

I get probing questions in here when I pass on things we hear at museum talks and people start needling. If you did thath in the presentation, you'd be asked to leave. The public is there to hear the pilot / famous peron talk ... not to hear a member of the audience argue with the guest.

So I do NOT say the real aircraft was available in 1940 and never have. I said the plans may have been compromised, and they well may have ... or not. It is something to consider, not to state as an absolute.

 

[drgondog]

Drgondog,

I know the history of the XP-4Q airframes. What I'm talking about is the idea for the design that was originally put on paper. I have heard the design was drawn up in early 1940, but there were other priorities at the time for Curtiss. Since I wasn't around, I cannot either confirm or deny this and I suspect that none of us in here can. Naturally, the USAAC felt they owned the designs since they were the customer for the P-40.

The entire point is that you keep referring to a connection for which there are no facts, or opinions based on facts from those whose opinions could be respected. For example some Curtiss designers that can cite dates and details?

If Curtiss 'did a few drawings' the drawings/plans were either funded by Curtiss or funded by USAAF. If by AAF there would be a contract number with first two digits being the year it was awarded. Any references disclosed or cited for the XP-40Q? If not, why just 'pick a year' and/or state 'I heard it somewhere'.

While the design may or may not have been the government's to show to a competitor, Curtiss may have had little practical shoice since teyw ere dependent upon the government for survival.

There is no evidence to suggest or support a conclusion that the 'government' 'showed or divulged' Curtiss data or had control of the data that Curtiss sold to NAA for $50,000 in early May 1940. Do you have facts, references to support your speculations?

I posted what I heard. I do not claim that it was absolutely so, I passed on what I heard. If you had been there, you'd have heard it, too and would be free to make your own arguments or conclusions after the fact.

I got that you 'posted what you heard'. If I had been there I would have asked questions about the facts and the background of a claim that is quite extraordinary given the timelines.

I get probing questions in here when I pass on things we hear at museum talks and people start needling. If you did thath in the presentation, you'd be asked to leave. The public is there to hear the pilot / famous peron talk ... not to hear a member of the audience argue with the guest.

You get probing questions because you state things with conviction based on presentations and discussions that seem to be consistently absent facts or sources. Most folks on this forum get jammed when they pontificate about questionable conclusions or statements with no visible support. Some (pontificators) are hurt when pressed for sources and blame it on mean or argumentative folks who don't accept speculative positions without logic or facts. Some of your presenters may fall in that category.

So I do NOT say the real aircraft was available in 1940 and never have. I said the plans may have been compromised, and they well may have ... or not. It is something to consider, not to state as an absolute.

Greg - posing the question 'did NAA base their Mustang design on the XP-40Q ?' and then continuing to support your statement when others present multiple and credible facts and information to contradict your 'speculation', while you fail to deliver a shred of evidence to support your speculation, reduces your credibility rapidly.

It's not just defense of the author of the comment, but your own lack of due diligence in making any assertion that you haven't verified - I've experienced that moment of 'oops' but I don't feel picked on when I get clobbered for opening mouth and inserting foot. Nor do most of the posters that are still on the forum after some of the raging debates over stuff that have LOTS of facts to work with.

One of the reasons I spent a LOT of time cross referencing statements made by 355th vets when I was researching the history is that a Lot of recollections about 1943 when solicited in 1980 made it clear that fact verification needed to be the rule of the day. I can recollect a specific argument (disagreement) I had with Yeager that visibly irritated him regarding whether the Square D 100th was 3rd Division when he commented that it was 1st. His specific comment was "G-- D--n It! I was There!!" Had John Sublett (another 357 ace) not 'corrected' Yeager in the conversation it would have been simply stupid to pursue even though I KNEW he was wrong. Yeager was irritated at Sublett, then

Conclusion drawn.. being there was not always a guarantee of accurately reciting facts..

 

[Shortround6]

Yeah, there were a whole bunch of other priorities at the time for Curtiss.

The P-46, the P-53 (which did use some P-40 parts and a laminar flow wing, a possible source of confusion?), The P-55, The P-60 ( including a few pieces of the P-53 and by extension a few P-40 pieces) and a few more fighter designs.

Strange that with "plans" for the P-40Q apparently sitting a drawer somewhere they spent so much time, money and effort on all these other programs.

What is really strange is that everybody admits/agrees that NA got to look at the data/plans of the P-40 and P-46. The dispute seems to be what use NA made of this information, if any. What is even stranger is that IF NA used any of this data it was the Aviation deal of the century because for $46,000 they apparently got exclusive use of the information rather than just a look at the information. NO Curtiss aircraft used a radiator set up like the P-51 and NO Curtiss aircraft used a wing quite like the P-51s wing.

 

[drgondog]

Dead on, Shortround. In addition there is no data or presented facts even hinting that the data purchased from Curtiss was a.) interesting, or b.) used, or c.) used by Curtiss in subsequent designs including the P-46 which was far from wind tunnel stage, or subsequent Curtiss designs.

The most wide spread version of the Purpose of purchasing the data was so that Kindleberger could state that NAA was prepared to build P-40s for the RAF if the NA-73 was a failure.

I have researched this across both the History of Curtiss and all the mainstream Mustang histories and have yet to find a definitive statement that NAA even opened the container of Curtiss supplied data, or when the data was actually delivered - much less an inventory of the data or a suggestion of any XP-46 aero data or any theoretical derivative of the P-40 family used in any way toward the Mustang design.

Yet the 'stories' and claims all seem to come from folks that a.) had nothing to do with the Mustang design, or b.) had nothing to do with P-40/53/55/60/40Q designs.

 

[The Basket]

Did the P-40 design go as far as it could go? Or was there any meat left for it go into production 1945?

 

[drgondog]

What did the P-40 have to offer when there were more P-51s and P-47s than could be deployed coming off the production lines.