Tilt rotors vs. helicopters-- manueverability in VT mode.

[Charles Gray]

Just a question-- how does the X-15 or the V-22 compare to a real
helicopter when hovering? Can they do helicopter style manuvers, or
are we talking more just up and over on the way to horizontal flight?

[Jim Burt]

Lightly loaded, either can do a full range of hover maneuvers. Forward,
backward, sideward, up and down. Heavy, not necessarily so. But then, the
same is true of conventional helicopters. . . .

"Charles Gray" > wrote in message
...
> Just a question-- how does the X-15 or the V-22 compare to a real
> helicopter when hovering? Can they do helicopter style manuvers, or
> are we talking more just up and over on the way to horizontal flight?

[George Vranek]

"Jim Burt" > schrieb im Newsbeitrag
...
> Lightly loaded, either can do a full range of hover maneuvers. Forward,
> backward, sideward, up and down. Heavy, not necessarily so. But then,
the
> same is true of conventional helicopters. . . .
>
> "Charles Gray" > wrote in message
> ...
> > Just a question-- how does the X-15 or the V-22 compare to a real
> > helicopter when hovering? Can they do helicopter style manuvers, or
> > are we talking more just up and over on the way to horizontal flight?
>
The tiltrotors have not optimal rotors for hovering and not optimal props
for crusing, Therefore they are les effective in hovering than conventional
helicopters and slower than conventional turboprops in cruising. The only
way, to fly fast with a helicopter is to stowe the rotor blades after the
vertical take off and convert so the helcopter into a fixed wing airplane.
please have a look at www.diskrotor.com .
George

[Helowriter]

The V-22 in helicopter mode flies like a CH-47 or CH-46 tandem. It
hovers, turns, and maneuvers like a helicopter. Fly-by-wire controls
smooth the transition from helo to airplane mode. That said, the
proprotors were cropped to fit Marine amphibious assault ships, so the
V-22 has higher disk loading than an optimized helicopter. That means
it can't carry as much as efficiently as a tandem rotor of the same
size/weight. A V-22 would not be an efficient aircraft for Vertical
Replenishment with lots of hovering. Autorotation capability won't be
as good as a helicopter -- hopefully, you don't have to do it. The
tilt rotor can however cover long distances as an airplane faster and
more efficiently than a helicopter, and that's the payoff.