Northrop FT-1 / FT-2 / BT-1 / BT-2
While Northrop was working on the YA-13/XA-16 developments of the Gamma, the company was also testing a scaled-down version for the US Navy under the designation Northrop XFT-1. This was one of two Northrop prototypes which failed to attract production orders, the other being the Type 3-A of 1935. Both were all-metal fighters, the XFT-1 with fixed landing gear being intended for the US Navy. Powered originally by a 466kW Wright XR-1510 radial, it was later re-engined, as the XFT-2, with a 485kW Pratt & Whitney R-1535, but crashed three months later, in July 1936.
The Northrop 3-A was a similar design for the US Army, but differed from the navy aircraft in having retractable landing gear and a modified canopy. Developed alongside these prototypes was the XBT-1, which had semi-retractable landing gear, and this entered production as the BT-1 torpedo-bomber, the first of 54 being delivered in April 1938. The BT-1 had a 615kW Pratt & Whitney R-1535 Twin Wasp Junior radial engine, but one aircraft was modified as the BT-2 to have revised landing gear and a 597kW Wright XR-1820 Cyclone. With other modifications this was to become the Douglas SBD Dauntless as the original Northrop Corporation had by then become the El Segundo Division of Douglas.