Re: V-22 Osprey is the Cover Story for the Current Issue of Time Ma...

OldSchool wrote:
On Oct 7, 11:23 pm, some...@xxxxxxxxxxx wrote:
In article <i89Oi.122421$Xa3.11611@attbi_s22>, Rufus <n...@xxxxxxxx> wrote:
Pat Flannery wrote:
Rufus wrote:
Mostly it's a matter of forward speed, and maintaining blade
rotational energy. Altitude has little to do with it other than
determining how fast you need to get the thing down - gross weight at
time of failure is a bigger concern. The trick it to save enough
rotational energy to convert forward speed to vertical lift somewhere
near impact...er, touchdown.
Which brings up a good point; just how is this in regards to a hard
landing?
Our helicopters are designed to take a pretty hard landing and crush in
a way that allows the crew to survive.
What about troops in the back of a Osprey? There's a good chance the
wings are going to snap at the junction with the fuselage when it comes
down hard due to the mass of the engines at the end...then the rotors
will hit the ground and shatter, throwing debris all over the place.
In vertical flight mode, they've managed to recreate a helicopter layout
in far smaller scale that never worked in practice, the Mil V-12:
http://avia.russian.ee/helicopters_eng/mi-12.php
Yeah...the inside of a V-22 is about the same volume as an H-53, so it's
a lot of mass for not so much interior space, IMO. And again, I'm
pretty sure that the prospects of doing a rolling landing are minimal if
not nil, so...
I have some video of what happens to a V-22 during a rotor strike - it
was aired on 60 Minutes some years ago, of an incident that took place
on the pad at NATC. Not pretty...someone involved once told me what had
actually happened during that test, but I forget what they said.
Harriers, OTOH, are something I know a great deal about. They don't
glide very well either. Most serious Harrier engine failures are
catastrophic...you either elect to eject, or to do a conventional
landing. Not much more to consider than that.
The British took the auxiliary air turbine generator off of the Harrier,
because they didn't want the pilot to even try to restart the engine if
it shut down. They had instances where the pilot would try a restart
without realizing just how severe the sink rate in gliding flight was
and wouldn't try to eject till it was too late.
Yes - the APU on a Harrier supplies high pressure air only, and not
electrics like a true APU.
There is still an airstart button on the throttle in a Harrier - the fan
is big enough to keep the engine rotating during engine out forward
flight if you watch your airspeed. Like with all turbines, you have to
be in a specific speed/altitude box to maximize chances of a successful
relight.
TheStarshipwas discontinued because the structural aging of
composites was/is not fully understood, and Beech wasn't inclined to
assume the financial risk of being liable if one came apart in the air.
I talked to someone who had flown one, and it had a odd problem in
regards to its composite structure. The composites were a very good
insulator and the heat of the cockpit avionics couldn't escape... so by
the time you had been airborne for half an hour, the cockpit was over 90
degrees.
Pat
That's interesting...hadn't heard that. That would certainly aggravate
composite fatigue...particularly for a pressure cycled airframe.
I used to see one coming into the airport at Vegas from time to time. I
have to assume it's probably Rutan's bird. They land flat and hot, like
most canard configured aircraft. But they sure are/were neat.
he the one with his own graveyard?- Hide quoted text -

- Show quoted text -

FWIW: not all Starship's were leased. I didn't know Rutan had one,
but if he did he turned it in. He hired Bob Scherer to fly chase
during SpaceShipOne missions. Scherer has 3 of the birds (i think)
and purchased several truckloads of spares from Raytheon to keep 'em
going. He was also in a documentary about the Starship on Discovery
or History Channel a couple of years ago


I didn't realize that Rutan had a hand in the design of the aircraft until some years ago - and a friend of mine that's more in the know had told me he had owned one, so it would make sense that he would hang onto it - I know I would have. Makes sense for the purchased ones...I know I used to see the odd one in Trade-a-Plane from time to time, but that was some years ago.

I know Raytheon/Beech supposedly cut up the ones they took back, so spares should have been available by the truckload to the proper bidder.

--
- Rufus
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