- 20 июня 2018, 20:12
SECOND-GEN TILTROTOR: We Got a Closer Look at the Flying V-280 Valor.
Bell is keen to show off the V-280’s fixed engine nacelles. This is a departure from the V-22 which has tilting nacelles where the engines and rotors pivot together when switching between cruise and hover mode.
The downside to the V-22’s design — when in hover mode — is that the intensely hot exhaust jets from the nacelles direct downward toward the ground. This limits disembarking troops’ room to maneuver (on the Osprey, they exit down a rear ramp), can spark an occasional grass fire, and can contribute to brownout conditions which have caused crashes.
Not so on the V-280. The Valor’s rotors adjust into vertical and forward positions for vertical and cruise flight, but the wingtip engine nacelles don’t move, keeping the hot engine exhaust directed high up and rearwards. Lower disk loading — the weight the rotors must lift — further helps reduce downwash.
It’s an engineering feat, and adds a lot of space for disembarking troops for whom every second — and inch — matters when setting up a perimeter or returning fire at an enemy after exiting from the aircraft’s six-foot-wide side doors. Similarly, fast-roping from the V-280 should be a smoother ride given the direction of the exhaust.
And with a cruising speed of 280 knots, the venerable UH-60 helicopter it’s replacing in some roles will get left in the dust.