Twin-engine Curtiss P-40C 41-13456 ...

[Mark Allen M]

Curtiss P-40C 41-13456 modified in 1942 to become a mock-up of an undesignated twin-engine fighter. W/o 18 Feb 1943 at Craig Field, AL; Condemned Feb 27, 1943.

"In 1942 the engineers of the Curtiss-Wright Corporation developed a twin-engine heavy fighter based on the P-40 model.

The project followed the same philosophy of design used in the Grumman XF5F-1 and XP-50, the I.M.A.M. Ro.57 and the Westland Whirlwind interceptors.
A mock-up was built using the airframe of P-40C 41-13456, the cockpit of a P-40D and two Packard V-1650-1/Merlin XX engines and nose cowling from two P-40F's.

Based on the only picture known to exist. Apparently the airplane would have had a great longitudinal instability and bad landing performance. Perhaps these were the reasons why it was never manufactured".

Biblography
Curtiss Aircraft, Putnam
Squadron Signal "Curtiss P.40 in Action" by Ernest R. McDonnell




Below is the original P-40C 41-13456. Location & Date unknown, other than somewhere grazing with some cows.

[Mark Allen M]

Another possibility that never made it to reality.

Twin XP-40- One of the more extreme P-40 modifications proposed
was a twin-engine version. No military designation was assigned and
no Curtiss model number is known but it did get to the full mockup stage
using the fuselage of P-40C (41-13456) and two Packard V-1650-1 engines.
Nothing came of this late 1942 project.





A twin-engined P-40C

"Amidst the twin-engined fighter projects intended for the US Army during the 30s and 40s, there are some of the lesser known in the whole History of aviation: notably, we allude to the twin engined version of the P-40 and to the Curtiss XP-71 project.

In regards to the first one, we only know it was designed around 1940 and that in 1942 [line missing] (which could have even been a flying prototype) made up of the fuselage of a P-40C (s/n 41-13456) joined to a modified wing with the engines on top, to keep the propellers sufficiently far away from the ground.

It's possible that this project, of which no documentation is left, was part of a series of concepts for a High-Speed Fighter, a sort of forerunner to the XP-71, about which we'll write later on.

In regards to the mock up we talked about before (static or flying) we only have one picture we know of, and we can presume that it would have used the same engines employed on other Curtiss-Wright projects of the era, like the traditional V-12 Allison V-1710-39 (F3R), the 24-cylinder Pratt & Whitney XH-2600 or the inverted V-12 Continental XIV-1400-3 Hyper, all of them water cooled, although for the production run were chosen two Packard (Rolls-Royce) V-1650-1 Merlin developing 1300 hp (or at least that's what relate the very few informations available). Such a progression in regards to the powerplant choice, can give us a chronological reference for the project, due to the fact that all those American experimental engines were under development during the 30s, while the Merlin became available only towards the end of 1940.

We have no known reference about its possible first flight, and it could even be there never was one.

At the roots of what we ourselves called the Twin P-40 - as no official designation for it is known - was surely the will to make a leap forward in regards to the previous P-36, XP-37, XP-40 and XP-42, but also the attempt to jump into the tender spawned by the Circular Proposal 39-775 for a high altitude interceptor. As we know, its winner was the Lockheed XP-49 while the Grumman XP-50 placed second.

The available documentation doesn't mention what the other two proposed projects were and in which order did they place, but it could be that the P-40 Twin came fourth during the evaluation trials that took place in the second semester of 1939.

It's clear, though, that Curtiss kept on developing it for over a year, seeing that both airframe and engine became available only in 1941.

For sure it was thought that the P-40 Twin could be a useful testbed for other contemporary programs".

[JohnB]

You have to give Curtiss credit for trying to milk the design for all it was worth.

Still, as related elsewhere here, they still stopped sending the type overseas and production stoped well before the end of the war.

There are a lot of good books on Mustangs, Spitfires and the like, it would be interesting to read an objective history of the P-40 (and Curtiss) in the war.

I get the impression that the USAAF was less than impressed by the firm and its products during the war.
Quite a comedown from its position as the leading fighter supplier in the biplane era with its "Hawks".

Last edited by JohnB on Wed Aug 14, 2024 12:05 am, edited 1 time in total.

[Mark Allen M]

It would be interesting to know when and where the last P-40 combat mission occurred. Both AAF and Allies.

[Chris Brame]

Great project for the R/C or flight simulator folks to try.

[quemerford]

I've seen a few scale models of these: they look familiar yet weird at the same time.

I suspect the last combat use of a P-40 might be Royal Australian AF?

[Duggy009]

The Dutch used P-40N's against Indonesian insurgents till 1950.
Link - http://axis-and-allies-paintworks.com/e ... p?id=17896

[quemerford]

The Dutch used P-40N's against Indonesian insurgents till 1950.
Link - http://axis-and-allies-paintworks.com/e ... p?id=17896

Every day's a school day! Thanks for posting

[k5083]

Great project for the R/C or flight simulator folks to try.

IRIS did a twin P-40 for Flight Simulator X. It was similar to the RL one but was based on the P-40E because that was the variant they had modeled previously. That may be accurate though because the fuselage in the above photo looks much more like an E/F than a C. Despite the recycling of the serial, there may have been little or no P-40C in that project. It is now available for free. I can't speak to how conjectural the flight model is.

August

[JohnB]

The rear 3/4 photo of the twin P-40 seems to be one of the few photos out there. It's the one that always cones up.
Any different shots of it?

There are a lot of good books on Mustangs, Spitfires and the like, it would be interesting to read an objective history of the P-40 (and Curtiss) in the war.

I get the impression that the USAAF was less than impressed by the firm and its products during the war.
Quite a comedown from its position as the leading fighter supplier in the biplane era with its "Hawks".

[Larry Kraus]

For what it’s worth, there was an old thread on this topic. Not much different information, but a few interesting links. There’s a reference to Marlin engines. I’m assuming that they meant Merlin engines.

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