Sikorsky-Boeing SB-1 Defiant Helicopter Completes Maiden Flight

Sikorsky Boeing SB-1 Defiant helicopter completed its first maiden flight at Sikorsky's West Palm Beach, Florida site on Thursday.

The aircraft, developed by Sikorsky, a Lockheed Martin subsidiary, and Boeing, will help inform the next generation of military helicopters as part of the United States (US) Army's Future Vertical Lift program, the company said in a statement.

The Defiant is based on Sikorsky's X2 platform and is a joint multi-role medium-class demonstrator that features a lift system using two coaxial main rotors and a rear-mounted pusher propulsor to solve the problem of retreating blade stall. By using two main rotors that spin in opposite directions, the Defiant counters the tendency of helicopter blades to generate uneven lift forces at high speeds, which severely limits the capabilities of current rotorcraft.