Tilt rotor - En kikk på Bell V-280 Valor - FlightGlobal

Anatomy Of Bell V-280 Valor Graham Warwick The Bell V-280 Valor is an advanced tiltrotor developed for the U.S Army’s Joint Multi-Role Technology Demonstration, a precursor to the Future Vertical Lift program. The V-280 first flew Dec. 18, 2017. Bell aims to achieve a speed of 280 kt. with twice the range of a comparable medium-lift helicopter. But the critical goals are to demonstrate that a tiltrotor can be affordable and have hover performance and low-speed agility equivalent to a helicopter.

Credit: Bell

1 | Dynamic System The elastomeric hub spring allows a high flapping angle to increase the rotor control margin and provide Level 1 handling qualities and high agility in low-speed flight. The wing shields side doors from rotor downwash. In a hard landing, rotor rotation ensures that dynamic components shed away from the fuselage. 2 | Fixed Engines The 4,750-shp GE T64-419 engine remains horizontal; the proprotor and gearbox rotate. This eliminates exhaust impingement on the ground and leaves side doors clear for access/egress and field of view/fire. It also reduces testing to qualify the engine and systems in the nonrotating nacelle. Redundant systems are split 2:1 between nacelles for separation. All fuel is in the wing. 3 | Tailwheel Landing Gear The tailwheel landing gear allows long sliding doors and leaves the nose free for sensors. The tailwheel is actively steered. High-set engines and lack of a tail rotor improve safety on the ground. The aircraft has triplex-redundant digital fly-by-wire controls and triple 3,000-psi hydraulic systems.

Credit: Bell Concept

4 | Straight Wing The V-280 has a straight, constant-section wing with no dihedral, for simpler, cheaper construction. Skins are carbon-fiber broad goods with large-cell carbon core stiffening (no stringers) for simple layup. The spar has a constant contour and ply count from root to tip. Carbon-core-sandwich webs are room-temperature-bonded to skins, eliminating fasteners. Labor hours are reduced almost 60% and tooling costs 50% compared to the V-22 wing.