LuZ asked:
If a CH-47 were to fly so the rotors were disposed to the left and right as opposed to fore and aft would it enter into AVRS if it followed the flight profile flown by the V-22 when the accident occurred?
Well Lu, it depends. Maybe IF the CH-47 rotors were spaced far apart like those of the tiltrotor.
But the CH-46 and CH-47 are nothing like tiltrotors. Can't compare 'em! For one thing, their rotors overlap by...what...nearly half? Because of this, the rotors tend to act in unison - as one big rotor. For another thing, the rotors are oriented fore-and-aft. *IF* the front rotor of a CH-47 happened to get into VRS, the nose of the aircraft would pitch down and it would begin to recover even without action on the part of the pilot. Asymm-VRS is simply not a problem.
A tiltrotor is more like two helicopters flying in formation. The proprotors do not overlap; they are spaced widely apart. In low-speed hovering flight, they interact and interfere with each other.
We do not hear much about VRS in CH-47's, primarily because it is no more of an issue than for a "regular" helicopter and therefore doesn't show up in the Fatal Accidents column. The problem with Asymm-VRS in a tiltrotor is that it will always lead to a fatal accident. It's already happened once.
And I wonder when the
next one will be?