Bell’s V-280 advanced tiltrotor and Sikorsky-Boeing SB-1 coaxial compound helicopter will now compete to replace the US Army’s UH-60 Black Hawks under its Future Long Range Air Assault (FLRAA) programme.
On March 16, the Army awarded Competitive Demonstration and Risk Reduction contracts to Bell and Sikorsky-Boeing teams for the next stage of its Future Long Range Air Assault (FLRAA) programme. Under the risk reduction agreement, the teams will refine their designs, prior to a fly off competition scheduled for 2022 that will decide which rotorcraft the US Army selects as its next workhorse.
The V-280’s latest flight statistics includes forward flight at 280 knots true airspeed, over 85 hours of flight and 180 rotor turn hours, in-flight transitions between cruise mode and vertical take-off and landing, 45-degree banked turns at 200 knots indicated airspeed, 4500 feet per minute rate of climb and sustained flight at 11,500 feet altitude, single flight ferry of over 370 miles, and fly-by-wire controls.
The SB-1 Defiant, V-280’s competitor, 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.