Sikorsky S-67 Blackhawk

The Sikorsky S-67 Blackhawk was a private-venture prototype attack helicopter that Sikorsky built in 1970 with its own research and development funds. It was a tandem two-seat aircraft designed around the dynamic drive and rotor systems of the Sikorsky S-61, and it could serve as an attack helicopter or carry up to eight troops into combat. It followed Sikorsky S-66 bid for the US Army Advanced Aerial Fire Support System programme, and it first flew on 20 August 1970.