Northrop YA-13

The Northrop YA-13 was a single attack aircraft built as a company funded demonstrator on the Northrop Gamma 2C, a development of the earlier Gamma 2A and 2B designs that had been created mainly for racing and speed record work. For the Gamma 2C the cockpit was moved forward to a conventional position, and the United States Army Air Corps evaluated it in mid-1933, then bought it after modifications and designated it YA-13. Testing at Wright Field showed it was underpowered, so its single row radial engine was replaced with a more powerful twin row radial and a three blade propeller, and the aircraft was redesignated XA-16. The change swung it from underpowered to overpowered. Northrop was already working on a parallel attack design that became the A-17, the main single engine attack aircraft of the Army Air Corps in the late 1930s, and with that success the YA-13 and XA-16 programme never went beyond testing.