Subject: Number Forty in the Series--Curtiss P-40 (10 of 10)

From: [email-masked] (Joseph F Baugher)
Date: 8 Jan 93 17:26:05 GMT

>From Joseph F Baugher <[email-masked]>

The P-40Q was an experimental project which attempted to produce a 
really modern fighter out of the existing P-40.  The modifications 
were in fact so drastic that there was very little in common with 
earlier P-40 versions.  Two P-40Ks (serial numbers 42-9987 and 
42-45722) and one P-40N (serial number 43-24571) were extensively 
modified with revised cooling systems, two-stage superchargers, and 
structural changes which markedly altered their appearance.  The 
project was assigned the designation XP-40Q.  

The first XP-40Q was P-40K-10-CU ser no 42-9987 fitted with a new 
cooling system, a longer nose, and a four-bladed propeller.  The 
radiators were moved into an under-fuselage position, with intakes 
between the undercarriage legs.  

The most prominent XP-40Q feature, used on 42-45722 and 43-24571, was 
the cutting down of the rear fuselage and the addition of a bubble 
canopy as on the "XP-40N".  Later the wingtips were clipped.  The 
result was an aircraft which bore almost no resemblance whatsoever to 
its parent P-40 line.  The V-1710-121 engine was fitted with water 
injection, resulting in a power of 1425 hp.  Speed increased to 422 
mph at 20,500 feet, making it the fastest of all the P-40s.  An 
altitude of 20,000 feet could be reached in 4.8 minutes, and service 
ceiling was 39,000 feet.  Four 0.5-inch machine guns were carried by 
the prototypes.  Wingspan was 35 feet 3 inches (after clipping), and 
length was 35 feet 4 inches (2 feet longer than the P-40N).  

The proposed production models of the P-40Q were to have carried 
either six 0.50-inch machine guns or four 20-mm cannon, but the XP-40Q 
was still inferior to contemporary production Mustangs and 
Thunderbolts, and development was therefore abandoned.  Consequently, 
the production life of the P-40 ended with the N version.  

The second XP-40Q was briefly used for postwar air racing.  Registered 
NX300B, the second XP-40Q was an unauthorized starter in the 1947 
Thompson Trophy race.  It was in fourth place when it caught fire and 
had to drop out of the race.  

Sources:

  War Planes of the Second World War, Fighters, Volume Four, William Green,
  Doubleday, 1964.

  The American Fighter, Enzo Anguluci and Peter Bowers, Orion Books, 1987.

  United States Military Aircraft since 1909, Gordon Swanborough and Peter
  M. Bowers, Smithsonian Institution Press, 1989.

  Curtiss Aircraft, 1907-1947, Peter M. Bowers, Naval Institute Press, 1979.

Joe Baugher       AT&T Bell Laboratories    2000 North Naperville Road 
		  Naperville, Illinois 60566-7033.   (708) 713-4548