The Sikorsky–Boeing SB-1 Defiant (stylized as "SB>1"; company designation S-100) is the Sikorsky Aircraft and Boeing entry for the United States Army's Future Long-Range Assault Aircraft program to replace the Sikorsky UH-60 Black Hawk. It is a compound helicopter with rigid coaxial rotors, powered by two Honeywell T55 turboshaft engines; it first flew on 21 March 2019. On 5 December 2022, the US Army selected the rival Bell V-280 Valor as the winner of the Future Long-Range Assault Aircraft program.