Subject: Number Forty in the Series--Curtiss P-40 (3 of 10)

From: [email-masked] (Joseph F Baugher)
Date: 24 Dec 92 21:22:27 GMT

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

In May 1941, the production lines at Curtiss were busy with a new P-40 
model--the P-40D.  It introduced a new engine, the Allison V-1710-39 
of 1150 hp.  This engine had originally been proposed for the 
experimental XP-46 fighter, but the USAAC had decided not to interrupt 
the P-40 production lines for a new type and decided instead to adapt 
the new engine to the existing P-40.  Substitution of the modified 
P-40 for the experimental P-46 was proposed on June 10, 1940, and 
Curtiss agreed to adapt the basic P-40 to the new engine.  The 
designation P-40D was assigned to the new project.  The P-40D was 
considered sufficiently different from previous P-40 versions that it 
was allocated a new company designation by Curtiss--Model 87.  

Even before the first P-40D had been built, the United Kingdom ordered 
560 examples for the RAF in May of 1940.  The airframe and engine 
changes justified a new name--Kittyhawk I.  An unspecified number of 
Model 87s had been ordered by France, but were never delivered.  They 
were designated Model 87-A1 by the company, but this designation was 
cancelled after France fell.  

The USAAF did not order the P-40D into production until September of 
1940, nearly 5 months after the RAF had ordered the equivalent 
Kittyhawk I.  

The P-40D introduced a new shorter nose design that was retained by 
all subsequent P-40s The 1150 hp V-1710-39 engine had spur gear 
reduction that raised the thrust line by six inches, giving a 
completely different nose geometry.  The overall length was reduced by 
six inches, the cross section of the fuselage was reduced, and the 
undercarriage was shortened.  The radiator was increased in size and 
moved forward.  Some 175 pounds of armor were added.  The fuselage 
guns were deleted, and two 0.50-inch machine guns with new hydraulic 
chargers were installed in each wing.  There were additional 
provisions in the wings for two 20-mm cannon, but these were never 
used.  Shackles were added under the belly to accommodate a 51-gallon 
auxiliary fuel tank or a 500-pound bomb.  Wing rack attachment points 
were provided for six 20-pound bombs.  

Gross weight of the D model was increased to 8670 pounds.  The climb 
rate and ceiling consequently continued to remain poor.  

Only twenty-two P-40Ds were produced with four wing guns.  US Army 
serial numbers were 40-359/381.  An order dated February 18, 1941 
increased the armament to six guns, and subsequent aircraft equipped 
with this armament were designated P-40E (Model 87-B2).  The cannon 
mounts were deleted.  Serial numbers of the USAAF P-40Es were 40-358, 
40-382/681, 41-5305/5744, and 41-13521/13599.  

The P-40E was powered by one 1150 hp Allison V-1710-39 twelve-cylinder 
Vee liquid cooled engine.  Maximum speed was 335 mph at 5000 feet, 345 
mph at 10,000 feet, and 362 mph at 15,000 feet.  Initial climb rate 
was 2100 feet per minute.  An altitude of 20,000 feet could be 
attained in 11.5 minutes.  Service ceiling was 29,000 feet.  Maximum 
range was 650 miles (clean), 850 miles (with one 43 Imp gal drop 
tank), 1400 miles (with one 141.5 Imp gal drop tank).  Weights were 
6350 pounds empty, 8280 pounds normal loaded, and 9200 pounds maximum.  
Dimensions were wingspan 27 feet 4inches, length 31 feet 2 inches, 
height 10 feet 7 inches, and wing area 236 square feet.  

The first Kittyhawk I (Model H87-A2) was flown on May 22, 1941, by 
which time the fighter had already been ordered by the US Army as the 
P-40D, the first production contract for which had been placed in 
September 1940.  They were comparable to the US P-40D, and were fitted 
with four 0.50-in wing guns.  Deliveries of the Kittyhawk I to the RAF 
began in August of 1941.  After the delivery of the first twenty 
Kittyhawk Is, the wing-mounted armament was increased to six 0.5-inch 
machine guns with 281 rounds per gun.  RAF serials for the Kittyhawk 
Is were AK571/999 and AL100/230.  72 Kittyhawk Is were diverted to 
Canada, the Canadian serial numbers being 1028/1099.  Out of this lot, 
seventeen Kittyhawk Is (AK601, 636, 680, 726, 778, 882, 931, 939, 960, 
971, 992, 995 and AL102, 178, 186, 188, 203) were transferred to 
Turkey.  

The Kittyhawk IA was the RAF designation for the British equivalent of 
the US P-40E.  Company designation was H87-A3, -A4).  The designation 
P-40E-1 was adopted slightly in advance of the Block Designation 
system to identify the 1500 Kittyhawk IAs supplied to Britain early in 
the Lend-Lease program and to distinguish their British equipment and 
details from those in US service.  They were virtually identical to 
the P-40E with the exception of British equipment such as radio 
installations.  Since they were procured with US funds, the planes had 
standard Army designations and were assigned Army serial numbers.  US 
Army serials were 41-24776/25195 and 41-35874/36953.  The RAF serial 
numbers were ET100/999 (equivalent US serials were 41-24776/25195 and 
41-35874/36353) EV100/699 (equivalent US serials were 41-36354/36953) 
Many were retained for US service but retained British camouflage.  
Six went to Brazil.  Twelve were sent to Canada in March 1942, while 
many others were shipped directly to Australia for use by the RAAF.  
Australian serials were A29-1/163.  Canadian serials were 720/731.  
New Zealand serials were NZ3001/3044, NZ3091/3098, NZ3100/3108, and 
NZ3271.  

Kittyhawk Is and 1As became operational with the RAF in the Western 
Desert on January 1, 1942.  They were used against Rommel's Afrika 
Korps and the Italian forces in North Africa throughout the year.  
They were used primarily at low altitudes and for close support.  The 
climb rate and the ceiling of the fighter were relatively poor, but, 
fitted with bomb racks beneath the wings from June 1942, the Kittyhawk 
wrought havoc among Rommel's armor.  The Allison engine's poor 
high-altitude output limited the overall performance of the Kittyhawk 
to a point well below that of the Bf 109F.  

A few P-40Es were converted as two seat trainers by replacing the 
fuselage fuel tank with a second seat.  

The AVG in China had been working its P-40Cs (Tomahawk IIBs) pretty 
hard throughout January and February of 1942.  Some were destroyed on 
the ground during Japanese strafing attacks, and others were lost in 
accidents.  Cannibalization provided spares for those for those that 
could be kept airworthy.  No more than 55 Curtiss fighters were 
available to the AVG at any one time.  Without replacement, losses 
mounted rapidly and the AVG was down to some twenty P-40Cs by March of 
1942.  That month, thirty P-40Es were transferred to China by air from 
Accra in Africa.  The improved performance offered by these more 
potent P-40s was very useful against the Zero fighters which were 
becoming more numerous in the Chinese theatre.  The AVG was absorbed 
into the USAAF as the 23rd Fighter Group on July 4, 1942.  At that 
time, it had been officially credited with the confirmed destruction 
of 286 Japanese aircraft as against the loss of only 12 aircraft shot 
down, 8 pilots killed in action and four missing.  Most of the losses 
were on the ground, with 61 aircraft destroyed by Japanese strafing 
attacks or lost in accidents.  The top scoring AVG ace was Robert H.  
Neale, credited with 16 kills.  Eight other pilots claimed ten or more 
victories.  The Flying Tigers accounted for more victories in 
proportion to their numbers than any other P-40 unit.  

There is a P-40E on display at the Wright-Patterson Air Force Base 
Museum.  I am unaware of its serial number.  

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.

  The Curtiss P-40 Tomahawk, Ray Wagner, Aircraft in Profile, Volume 2,
  Doubleday, 1965.

  The Curtiss P-40 Kittyhawk I-IV, Ray Wagner, Aircraft in Profile, 
  Volume 6, Doubleday, 1969.

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