This aircraft, a modified K-2, was the first autogiro tested by the Army Air Corps at Wright Field in 1931.
Kellett K-2/K-3
Autogiro
The Army Air Corps bought a small number of Kellett YG-1s, the first practical rotorcraft procured by the U.S. Army, at the end of the 1930s. The Air Corps later tested the K-2 and K-3 versions of the Kellett, but they lacked the performance necessary for military applications.