Dr Igor Bensen, formerly of Kaman, set up Bensen Aircraft Corp. in 1952 at Raleigh-Durham airport, N. Carolina, concentrating on ultralight rotorcraft. Following tip-drive and engine-above-rotor helicopters, Bensen produced B-7 Gyro-Glider, B-7W Hydro-Glider and B-7M Gyro-Copter, latter (40-hp Nelson) leading to thousands of simple autogyros of B-8 family.