The
Northrop P-61 Black Widow, named for
the American spider, was the first operational U.S. warplane designed as a night fighter, and the first aircraft designed to use
radar. The P-61 had a crew of three: pilot, gunner, and radar operator. It was armed with four 20 mm (.79 in)
Hispano M2 forward-firing
cannons mounted in the lower fuselage, and four .50 in (12.7 mm)
M2 Browning machine guns mounted in a remote-controlled dorsal
gun turret.
It was an all-metal, twin-engine,
twin-boom design developed during
World War II. The first test flight was made on 26 May 1942, with the first production aircraft rolling off the assembly line in October 1943. The last aircraft was retired from government service in 1954.
Although not produced in the large numbers of its contemporaries, the Black Widow was effectively operated as a
night-fighter by
United States Army Air Forces squadrons in the
European Theater, the
Pacific Theater, the
China Burma India Theater and the
Mediterranean Theater during World War II. It replaced earlier British-designed night-fighter aircraft that had been updated to incorporate radar when it became available. After the war, the P-61—redesignated the F-61—served in the United States Air Force as a long-range, all-weather, day/night interceptor for
Air Defense Command until 1948, and
Fifth Air Force until 1950.
On the night of 14 August 1945, a P-61B of the 548th Night Fight Squadron named "
Lady in the Dark" was unofficially credited with the last
Allied air victory before
VJ Day. The P-61 was also modified to create the
F-15 Reporter photo-reconnaissance aircraft for the
United States Army Air Forces and subsequently used by the
United States Air Force.