The first prototype of the Bell Helicopter V-280 Valor tiltrotor aircraft has been revealed undergoing ground trials at Bell Helicopter' Amarillo Assembly Center in Texas.
The next generation tiltrotor is being developed for U.S. Army's Future Vertical Lift program that intends to replace service’s Sikorsky UH-60 Black Hawk utility and Boeing AH-64 Apache attack helicopters.
The aircraft sporting registration N280BH is in its initial configuration, and is undergoing tethered ground trails ahead of first flight expected later this month.
Weighing half the 60,000 lb Bell-Boeing V-22 Osprey tiltrotor, the V-280 offers twice the speed and range of present generation helicopters.
The Valor is designed to have a cruise speed of 280 knots (320 mph), range of 2,100 nautical miles (2,400 mi; 3,900 km), and a combat range of 500 to 800 nm (580 to 920 mi).
It features a V-tail, a large cell carbon core wing with a composite fuselage, triple redundant fly-by-wire flight control system, conventional retractable landing gear, and two 6-foot (1.8 m) wide side doors for ease of access.
One of the unusual feature of the V-280 is that, the engine and rotor are in parallel axis, and only the rotor and gearbox system rotates vertical for takeoff/landing, while the engine remain horizontal.
The engine output shaft is connected to the drive system through a spiral bevel gearbox that transfers power to the fixed gearbox and proprotor gearbox, which rotates on two big spherical bearings driven by a conversion actuator mechanism. This new design is claimed to be lot simpler than the complex hyrdo-mechanical system used on the V-22 Osprey.
The demonstrator aircraft is powered by two GE T64 turboshaft engines, while production version will be powered by an advanced engine.
The fixed engine also enable reduced ground clearance, maximizes cabin ingress/egress clearance.
Unlike the V-22 Osprey, which uses the rear ramp for fast rope and hoist ops due to high rotor downwash while using the starboard doors, the Valor has reduced downwash which facilitate rappelling and hoisting through side doors.
The Valor will be manned by four crew members and can carry 14 troops. It can carry a useful load of 12,000 lbs or 10,500 lbs load on external sling.