The deferred deliveries of the
P-40 to the USAAAC were picked up again with the P-40B. In September
1940, 131 P-40Bs were procured by the Army to replace the deferred
P-40s The P-40B (Model H81-B) differed from the P-40 in having
an extra 0.30-inch machine gun in each wing, bringing the total
to four 0.30-inch guns in the wings. The two 0.50-inch guns
in the fuselage were retained. The engine was still the V-1710-33.
Serials were 41-5205/5304 and 41-13297/13327 (c/ns 15973/16103).
The first P-40B flew on March
13, 1941. The airplanes were delivered in full camouflage. In
contrast to the earlier P-40, the tail stripes and upper right
and lower port wing stars were no longer present, but a star
now appeared on each side of the fuselage. The P-40B retained
the same dimensions of the P-40, but weight was increased to
5590 pounds empty, 7326 pounds gross, and 7600 pounds maximum
loaded. Because of the additional weight, the P-40B had an inferior
performance to the P-40, maximum speed being 352 mph, service
ceiling being 32,400 feet, and initial climb rate being 2860
feet per minute. Normal range was 730 miles, but a maximum range
of 1230 miles could be attained at the minimum cruise settings.
The export equivalent of the
P-40B was the Tomahawk IIA (Model H81-A2). They differed from
the American version by having the wing guns replaced by four
0.303-inch Brownings. 110 were produced for the RAF. RAF serials
were AH881/990. 23 of these planes were transferred to the USSR,
and one (AH938) went to Canada as an instructional airframe.
War Planes of the Second World
War, Fighters, Volume Four, William Green, Doubleday, 1964.
The American Fighter, Enzo Angelucci
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.