Sikorsky-Boeing SB-1 Defiant

The Sikorsky-Boeing SB-1 Defiant, company designation S-100, was the joint Sikorsky Aircraft and Boeing entry for the United States Army Future Long-Range Assault Aircraft program, which aimed to replace the UH-60 Black Hawk. It is a compound helicopter with rigid coaxial rotors and a pusher propeller, powered by two Honeywell T55 turboshaft engines, and it builds on the earlier Sikorsky X2 design. The demonstrator first flew on 21 March 2019 at Sikorsky West Palm Beach in Florida and reached 247 knots in level flight in October 2021. In December 2022 the Army chose the rival Bell V-280 Valor, and the only prototype now rests in the United States Army Aviation Museum.