I'll take 2!
Everyone knows about the V-22 Osprey tiltrotor - the remarkable plane/copter combo craft around which the US Marines have based so many of their future plans, and which is at last in operational service after long a painful teething troubles. Relatively few, however, have been following the development of the Osprey's civilian …
I see why you may want one rather than the other two, as its maintanance costs that kill you over the long term, and having a plane that can do one side of europe to the other with out having to stop at an air feild to change into a 'copter is nice.
It also saves on air crew.
I am sure it will do well (or certainly as well as most copter/private jet firms).
The problem with VTOL is that it takes about 4 times as much power as a fixed wing plane. Compare the engines in light 'copters with those in light planes. So you have 75% excess power, with all the extra weight involved, for most of your flight. The longer the range, the worse it gets! And all for the sake of landing and taking off in restricted space. VTOL craft are notorious fuel guzzlers because of this.
The military have their reasons for wasting power and fuel. Civvies have to keep their eyes on the bottom line.
Rumour has it:
Don't go to vertical.
Feather prop on knackered engine.
Apply a boot-full of appropriate rudder and find a runway quick.
Tilt rotors a bit at the very last second on landing, to avoid those huge runway repair bills/bits of prop decapitating you.
NOW you can worry about the trousers and the seat unholstery.
Having done some market research on a similar idea to this a few years back (i was an engineering student not marketing i swear!) this will succeed if its marketed to the right industries.
Its faster then a helicopter so you get where your going faster, using less fuel along the way and then have the convenience of landing without a runway or if your doing something like search and rescue or geological survey hovering which you cannot do in a fixed wing. Yes maintenance costs are higher but a fixed wing cant hover and most of the fuel used by a helicopter is in getting to the destination you want to be operating at so by getting there faster you've just made the job cheaper.
Looks like a winner to me. Will never replace the standard helo or fixed wing but there's defintiely a niche there for it.
Spot on! One of the reasons the original Osprey was so late was the implementation of the cross-shaft arrangement to allow this.
I'd be more interested to see what would happen (from a safe distance or, ideally, on TV) if you got a prop or prop-drive failure. That buggers your two-for-one deal and with very large props mounted waaay outboard like that, anything that you can't feather is even more of a liability than usual.
That is not so much the problem; though helps asymmetric thrust 'issues' a lot.
"If one of the props failed, well you are still better off than if you were in a helicopter with a failed rotor and probably no worse than in a twin engine plane with a failed engine"
Not quite true; a twin engine medium turbo-prop with an engine out can cope with some asymmetrical thrust with enough rudder & trim, and perform a reduced power landing safely. A helicopter can (with enough height) go and autorotate with a rough landing.
As far as I know, tilt-rotors can't land with engines horizontal; (another point of failure - they can't rotate the nacelles then horizontal landing is going to be a nightmare with the massive rotors) so they have to rotate & land on 50% power, which cannot be so easy. I guess with the right height, they could rotate to vertical mode (with ground effect?) and land vertically ; I presume with the remaining engine at emergency power for a rough put-down. Maybe they can collapse the rotors for power-off horizontal landing though...
Still very sensitive to interconnected shafts; long, light-weight shaft's, handling thousands of horse-power coming on fast; one snaps with a power outage and the craft is going to flip very quickly with chances of survival being... not so good..
icon: one sick bird
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