The first American turboprop engine was the General Electric XT31, first used in the experimental Consolidated Vultee XP-81. The XP-81 first flew in December 1945, the first aircraft to use a combination of turboprop and turbojet power.
The T31 engine was the first American turboprop engine to power an aircraft. It made its initial flight in the Consolidated Vultee XP-81 on 21 December 1945. The T31 was mounted in the nose; a J33 turbojet engine mounted in the rear fuselage provided added thrust. The T31 was also used on the Navy XF2R-1, similarly powered by a turboprop/turbojet engine combination. The engine was to have been flown experimentally on a Curtiss XC-113 (a converted C-46), but the experiment was abandoned after the XC-113 was involved in a ground accident. Only 28 T31s were built; none were used in production aircraft, but improved production turboprop engines were developed from the technology pioneered by the T31.
A derivative of the T31, the General Electric TG-110, given the military designation T41, was ordered but subsequently cancelled.