Cierva and Pitcairn licensed the Kellett Autogiro Corporation of Philadelphia to build autogiros and the developed Kellett YG-1 of the late 1930s became the US Army's first rotary-winged aircraft. Seven YG-1B autogyro were procured by the US army in 1937 for observation duties.
YG-1A Year: 1936. Seats: 2. Engine: Jacobs L4MA7, 225 hp. Gross wt: 2205 lbs. Empty wt: 1586 lbs. Rotor dia: 40 ft. No of blades: 3.
YG-1B Year: 1937. Seats: 2. Engine: Jacobs L4MA7, 225 hp. Gross wt: 2400 lbs. Empty wt: 1617 lbs. Rotor dia: 40 ft. No of blades: 3.