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
Sikorsky Cypher Sikorsky Cypher The Sikorsky Cypher and Cypher II are types of unmanned aerial vehicles developed by Sikorsky Aircraft. They are vertical takeoff and landing aircraft which use two opposing rotors enclosed in a circular shroud for propulsion. In the late 1980s, Sikorsky Aircraft flew a small UAV named "Cypher", with coaxial rotors inside a torus-shaped airframe. The torus shroud improved handling safety and helped increase lift. The first proof-of-concept Cypher was 1.75 meters (5.75 feet) in diameter and 55 centimeters (1.8 feet) tall, weighed 20 kilograms (43 pounds), and was first flown in the summer of 1988. This design was