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.

[2] Sikorsky Aircraft and Boeing are jointly producing a medium-lift-sized demonstrator they named SB>1 Defiant[3][4] (also widely known as "SB-1")[5][6] for phase one of the program.

They say that factors outside their control, like budget cuts, "requirement creep", and a long development period caused problems with the Comanche and not team dysfunctionality.

Originally scheduled for 2017, delays arose due to a requirement to implement automated fiber placement blade manufacture at the request of the U.S.

[16] Dynamic systems such as turboshafts, transmission, and rotors were scheduled to be tested at West Palm Beach, Florida, by the end of October 2018, before ground runs in November, then first flight to reach 200 kn (370 km/h) within six months.

[22] In January 2021, Sikorsky-Boeing announced the Defiant X variant, specifically designed for the Future Long-Range Assault Aircraft program.

[25] On 5 December 2022, the U.S. Army selected the rival Bell V-280 Valor as the winner of the Future Long-Range Assault Aircraft program.

[27][5] Compared to conventional helicopters, the counter-rotating coaxial main rotors and pusher propeller offer a 185-knot (213 mph; 343 km/h) speed increase, a 60% combat radius extension, and 50% better performance in high-hot hover operations.

[28] However, Sikorsky plans to build the 30,000-pound-class (14,000 kg) JMR-TD (with a cabin 50% larger than the Black Hawk) at full scale to remove doubts about the scalability of the X-2 technology.