Sikorsky–Boeing SB-1 Defiant
experimental gyrodyne by Sikorsky and Boeing
The Sikorsky–Boeing SB-1 Defiant (stylized as "SB>1"; company designation S-100) was 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.
In December 2022, the U.S. Army selected the rival Bell V-280 Valor as the winner of the Future Long-Range Assault Aircraft program. The only existing SB>1 prototype now resides in the United States Army Aviation Museum.
Development
Sikorsky Aircraft and Boeing are jointly producing a medium-lift-sized demonstrator they named SB>1 Defiant (also widely known as "SB-1") for phase one of the program. Originally planned to fly in late 2017, its first flight was delayed in April 2017 to early 2018. Sikorsky led the initial development phase one with an aircraft based on their previous Sikorsky X2 design while Boeing plans to led phase two, which is the mission systems demonstrator phase. The Boeing-Sikorsky team was seen to have an advantage with their large industrial base that may result in wider support from Congress alongside their transport helicopters being widely used by the U.S. Army.
Up to 2013, Sikorsky and partners spent $250 million on X2 and Raider with a separate team and aircraft from the S-97 Raider.
“Sikorsky–Boeing SB-1 Defiant” enters the record as experimental gyrodyne by Sikorsky and Boeing. Crown Archives preserves that source wording while asking what Sikorsky, Boeing and SB-1 can confirm, complicate or overturn.
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