Sikorsky S-67 Blackhawk Sikorsky S-67 Blackhawk The Sikorsky S-67 Blackhawk was a private-venture, prototype attack helicopter built in 1970 with Sikorsky Aircraft research and development (R&D) funds. A tandem, two-seat aircraft designed around the dynamic drive and rotor systems of the Sikorsky S-61, it was designed to serve as an attack helicopter or to transport up to eight troops into combat. The US Army issued a request for proposals (RFP) for its Advanced Aerial Fire Support System (AAFSS) program on 1 August 1964. Lockheed offered its CL-840 design, a rigid-rotor compound helicopter. Sikorsky submitted the S-66, which featured a "Rotorprop" serving as a
Igor Sikorsky several former Russian military officers. Among Sikorsky's chief supporters was composer Sergei Rachmaninoff, who introduced himself by writing a check for US$5,000 (approximately $61,000 in 2007). Although his prototype was damaged in its first test flight, Sikorsky persuaded his reluctant backers to invest another $2,500. With the additional funds, he produced the S-29, one of the first twin-engine aircraft in America, with a capacity for 14 passengers and a speed of 115 mph. The performance of the S-29, slow compared to military aircraft of 1918, proved to be a "make or break" moment for Sikorsky's funding. In 1928, Sikorsky became