Bell V-280 Valor Tilt Rotor First Flight
Unlike the earlier Bell-Boeing V-22 Osprey the V-280, targeted to cruise at 280 kts, does not tilt its engines (two GE T64s) only its rotors. This eliminates engine lubrication complexity and reduces the hot efflux effects on the ground. To achieve this engine power is transmitted through a spiral bevel gearbox that transfers power to the proprotor gearbox. This rotates on two spherical bearings. Bell are clearly sensitive about the design solution as both video and photographs have been altered to blur the mechanism and preserve the Valor’s modesty.
In the event of an engine failure, power is transmitted by a cross-shaft, similar to that on the V-22, from the operative engine to the opposite proprotor.
The V-280 had previously conducted ground runs on a test stand at Amarillo, TX:
It features a triple-redundant fly by wire (FBW) control system.
UPDATE 26 February 2018: The V-280 has now flown for 9 hours and been rotors running for 56 hours. The first US Army pilot flew it 7 February 2018.
UPDATE 15 May 2018: V-280 has now completed a transition to forward flight and achieved 190 kts.
JMR-TD and FVL
The Bell V-280 Valor program is part of the Joint Multi Role Technology Demonstrator (JMR-TD) initiative, started in 2013, which runs into 2019. Construction of the V-280 began in June 2015.
The JMR-TD program is the R&D precursor to the Department of Defense’s Future Vertical Lift (FVL) programme that will be the basis for the replacement of the majority of US military rotorcraft and undoubtedly reshape the US rotorcraft industry.
The V-280 program brings together Bell Helicopter, Lockheed Martin, GE, Moog, IAI, TRU Simulation & Training, Astronics, Eaton, GKN Aerospace, Lord, Meggitt and Spirit AeroSystems (who make the fuselage) – collectively referred to as Team Valor.
Team Valor’s main rival for FVL is a team of Sikorsky (now part of Lockheed Martin!) and former V-22 partner Boeing, who joined forces to develop the SB>1 Defiant. This combines a coaxial rotor with a pusher propeller.