Page 30 - Volume 15 Number 1

IN HISTORY
Despite failure of the XA-21 and XBT-17 programs, in 1942 the Boeing Aircraft Company responded to an Air Corps competition to select an airplane to serve as a twin-engine advanced trainer. Before America entered the war, it had become increasingly apparent to Army brass that it would be necessary to train teams of men needed to fly bombers in combat. The aircraft’s specific mission would be to teach aircrew how to work together as a team before they were assigned to an operational training unit. The Wichita Division prepared a proposal that was based on a series of studies conducted during 1939-1940, known as Project 26.
Late in 1940 the company received a request for bid and submitted its design in October, but the Army’s requirements for an aircrew trainer had changed so radically that no further action was taken until April 1941, when Boeing received another request for proposals. The Army stipulated that the airplane had to be built using as many non-strategic materials as possible. Finally, after the Air Corps made more changes to its requirements, Boeing signed a contract to build two airplanes designated Model X-120 (Army XAT-15).
Full responsibility for the design and construction of these trainers was given to 90 engineers at the Wichita Division. They developed a sub-scale model and conducted tests in a wind tunnel at Wichita University. A full-scale mockup of the twin-engine ship was completed and inspected by Army Air Corps officials in July 1941. Working 10-hour days, the engineering department generated a steady flow of drawings and blueprints to the factory, and the first prototype was completed and made its first flight in April 1942. The X-120 was conventional in many respects, with a welded steel tube fuselage structure covered with plywood and cotton fabric doped and shrunk to a tight fit. The wing panels and empennage assembly were built of wood and covered with plywood and fabric.
The first airplane was delivered to the Army in October 1942. The Air Crops liked the XAT-15 and awarded Boeing an initial contract for 75 XAT-15s that was soon increased to 325 by February 1942. To further expedite construction, contracts for 360 airplanes were given to the McConnell Aircraft Company in St. Louis, Missouri,
23 32
28 • KING AIR MAGAZINE
JANUARY 2021