Sikorsky and Boeing have delivered the team’s formal proposal for the U.S. Army’s program to eventually replace the UH-60 Black Hawk helicopter.
On Sept. 7, the team submitted plans for the Defiant X coaxial compound helicopter to the Army as its pitch for the Future Long Range Assault Aircraft, or FLRAA.
“Today, Team DEFIANT completed and submitted the proposal for the U.S. Army’s FLRAA competition, offering low-risk, transformational capability that delivers on an Army critical modernization priority and advances the future of Army aviation,” Sikorsky President Paul Lemmo and Mark Cherry, vice president for vertical lift at Boeing Defense, said in a joint statement.
Defiant X is a refined version of the SB>1 Defiant developed by the two companies during the Army’s Joint Multirole Technology Demonstration (JMR-TD) program. Its primary competitor in that effort and for FLRAA is Bell’s V-280 Valor advanced tiltrotor.
“We believe we have a very compelling design for the Army,” Jay Macklin, Sikorsky’s director of Future Vertical Lift business development, told Vertical during a visit to parent company Lockheed Martin’s new Future Vertical Lift center outside Washington, D.C. “We’re very excited to be at this point. It’s been a long journey in a very short period of time.”
While Bell has grounded Valor after a 3.5-year flight test and data-gathering campaign, Sikorsky and Boeing continue to fly Defiant and expand the aircraft’s flight envelope. Because of developmental growing pains associated with its rigid composite main rotor blades and transmission system, SB>1 did not fly until 2019. Data gathered in the ensuing flight test campaign, including level flight at 230 knots, was incorporated into the team’s FLRAA proposal.
“Defiant X delivers speed where it matters, survivability, unsurpassed power, maneuverability, superior handling in any environment and lower lifecycle costs — while operating in the same footprint as the BLACK HAWK,” Lemmo and Cherry said. “We are confident that DEFIANT X, supported by our longstanding Army industrial base suppliers, is the best choice for delivering overmatch on the Multi-Domain Operational battlefield in INDOPACOM and across the globe.”
The SB>1 team released images of the revised Defiant X in January but have not provided much detail on what changes were made to the Defiant operational prototype before the official pitch was made to the Army. A formal request for proposals for FLRAA was released to industry in July. It outlined the Army’s need for an advanced rotorcraft capable of at least 230 knots and preferably capable of cruising 280 knots, much faster than traditional rotorcraft.
The FLRAA design has a noticeably pointier nose cone, relocation of the engine exhaust outlet from aft of the main rotor assembly, lateral reshaping of the airframe and tail boom and chevron-style tail fins. All are enhancements to the existing design that reduce Defiant’s thermal signature and improve aerodynamic handling, according to the Defiant team. Defiant X also has a tricycle-style landing gear with one wheel under the cockpit and two wheels aft whereas the operational protype Defiant sported two front wheels and a tail wheel that protruded down from its tail boom.
