V-22 Osprey is the Cover Story for the Current Issue of Time Magazine

Tilt rotor work can be said to have begun in 1953 (or even earlier) with the XV-3 built by Bell. In the 70s, the Army and NASA sponsored the development of the XV-15 which can really be thought of as the prototype for the V-22. So the development period for this aircraft can be 35-55 years, depending upon what "start date" one chooses.

See:

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Dennis

Reply to
Dennis Buley
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Nobody should die in plane crashes but the fact is they do, especially in aircraft with new technology. The only way to prevent deaths is to stop flying.

An old H-53 pilot/college professor told us he felt that the Marines were simply not trained or equipped to develop and flight test something like the Osprey. IMHO, that is the reason for it's safety record. As he pointed out, all those Marines who died in the cabin should have been sandbags.

Curt

Reply to
Curt

Oh, I know that! My older sister used to live under the approach path to one of the runways of the Minneapolis/St. Paul airport. We were sitting at dinner when suddenly it felt like a earthquake had hit, and Iran outside to see a 747 fly directly over me at around 500 feet altitude, appearing to move so slow that it looked like it was floating. :-)

Pat

Reply to
Pat Flannery

Bruce Burden wrote:

We had a couple of those also way, way, back:

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once talked to a pilot in the Navy aircraft test section (he went way back to the Tripartite Evaluation Squadron that flew the Kestrels in competition with the VAK-191) His story of what happened to the Osprey was this; the tilting wing design was much superior to the swiveling engine idea, in that it increased lifting power by not having the downwash of the prop/rotors fall on top of the wing, pushing it downward, allowed easy cross shafting of the engines, and allowed the wing control surfaces be used in vertical flight for easy control of the vehicle. But after LTV-Hiller-Ryan couldn't get a production contact for the XC-142, they sold the swiveling-wing patent to Canadair, as they were working on a VTOL cargo plane idea also:
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it came time to compete for the V-22 contract, an attempt was made to buy back the patent from Canadair, but they realized how important it was, and quoted a sky-high figure for it. Since the Bell XV-15 had proven successful during tests:
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V-22 had its design based on it. Unfortunately, the XV-15 didn't need to have a wing that would rotate 90 degrees to lay on top of the fuselage, a folding tail, or blades on its rotors that could be folded for storage; all of which were needed for compact storage on a helicopter carrier, and the ability to fit on its elevators. So something simple turned into something very complex, and we've been paying the price for it ever since. What the test pilot was really torqued off about was the cancellation of the A-12 Avenger II; he had done a lot of work on that program, and said that it would have been a great aircraft...but with the end of the Cold War the Navy wanted to put funds elsewhere and screwed over McDonnell-Douglas and General Dynamics to free up funds for other projects by claiming the plane was no good. He was getting very close to retirement, so felt he could get away with saying stuff like that. The reason he was at the airshow was to see one of the first appearances of the MiG-29 in America and see what he thought of it from a trained test pilot's perspective, so as to figure out what its potential was in air-to-air combat. He flew in in a TA-4J with a new Navy pilot; the kid was so awed by this guy that he was almost strewing rose petals in front of him when he walked. I think his having served three combat tours in Vietnam as a Skyhawk pilot and returning to the carrier on more than one occasion with his aircraft so shot up it had to be scrapped probably helped. :-)

Pat

Reply to
Pat Flannery

They had a great ad for it early on in the program showing a Navy one destroying a Soviet Typhoon submarine with a homing torpedo. Somebody wrote AW&ST saying that scenario indicated bad things going on in the world. I think it would make a lot more sense for Army rather than Air Force use. I had a 1/72 model of the V-22 by Testors around 15 years ago; I imagine it's a collector's item nowadays. When they make a model of something, and the model goes into and out of production and becomes a collector's item before the aircraft it's based on enters service, you've got a problem. Pat

Reply to
Pat Flannery

My cousin had one in 1/48th probably, because he worked for Vertol (or Boeing, as they like to call themselves now) :) I had the AMT/Esci 1/72nd kit but never got it built.

Bill Banaszak, MFE Sr.

Reply to
Mad-Modeller

Rufus wrote: : Bruce Burden wrote: : :> I am sure the V-22 can glide if it is in flight configuration. : : No, it can't glide in a true sense - it has to "auto-rotate : forward"... : Reference, please. It was a fixed wing. It will glide, for some suitable definition of "glide", so long as there is air passing over the wing and generating lift.

Now, if you are saying that the V-22 will auto-rotate, I will agree. Like a helo, it has to have a certain amount of altitude and/or airspeed to make that happen, however. : :> Besides - helos don't autorotate below a certain altitude/ :> airspeed either. : : A helo has to maintain forward speed to auto-rotate. : That is what I said. If you don't have the altitude and/or airspeed in a helo (or any aerocraft), you merely impact. Some times, airspeed and altitude don't do you diddly - re Challenger and Columbia. : : The problem is that you can't land the thing with the rotors tilted, and : if the cross-shafting is damaged it's all over anyway...engines running : or not. : Reference on the "can't land with the rotors titled", please.

What I can find is that the pilot must make a very fast determination on whether to attempt to enter an auto-rotation state, or attempt to glide to a landing. Given that emergencies, by their nature, require a very prompt decision by the pilot, I don't see this a being a unique situation (the prompt decision requirement).

I expect Harrier pilots make the same decision should the Pegasus engine decide to go on holidays.... : :> I also expect the V-22 has much better ditching manners than :> a helo ever hoped to have. : : I seriously doubt that... : Shrug. If the rotar/hubss snap off as designed, it will be safer that attempting to ditch a turbofan aircraft with engines under the wings (just about all large cargo and passenger aircraft). And given that the weight and balance of a helo is all very high on the airframe, I stand by my statement. : :> Has Mitsu given up on their V-22 design, where the entire :> wing rotated, unlike the nacells on the V-22? : : ...now that's just as scary. Maybe more so. : The only guarantee you can be sure of in an aerocraft is that it WILL return to earth at some point in the future.

At other times, there just does not exist a market for the aerocraft after all - re Beechcraft Starship. Leading edge design, but too expensive and perhaps too ahead of its time.

Bruce

Reply to
Bruce Burden

...try being eyeball to eyeball with a C-5A while flying a Piper Arrow sometime.

I'd rather stand on the approach threshold of a runway at ORD and have

747s pass over me all day than stand under one V-22...the thing just plain ain't natural.
Reply to
Rufus

Reference - I'm a degreed aeronautical engineer. The V-22 does not have enough surface area to sustain a true glide the way a fixed-wing aircraft can.

Yes - but when you figure the ability to tilt the rotors I'm not really certain what "auto-rotate" actually means for V-22. Any component of tilt robs from the lift vector, and so the optimum auto-rotation tilt should be 0 or 90 degrees...however they measure it wrt vertical.

The possibilities for failure modes are far more numerous compared to a standard helo...have no idea how they drive the tilt - hyd, electric, pneumatic...or what systems there are to fail, or cascade failures. Only know I've seen film of what happens when the thing gets squirrelly in ground effect - it ain't pretty.

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.

Thats pretty obvious, if you've ever seen one in operation...as I have. The rotor radius simply grossly exceeds the height of the rotors from the ground. Given that the aircraft will need to pitch down to maintain forward speed, I'd say the rotors couldn't be tilted much more than about 5 degrees without running the risk of a blade strike during a flared landing. And again, the specific mode of failure is a critical factor.

A V-22 won't "glide". Period. It will need to auto-rotate in some sense, and I'm not interested in being an eye-witness to that...

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. If you have the capacity to VL, you don't have an engine emergency...and even then, you will be limited by temperature, gross weight, or a combination of the two determining if you have the margin to VL - just like a helo's ability to hover is limited. Source of info: NATOPS.

What I meant was that it probably has no better ditching characteristics than any other twin-rotored helo, and that helos have far more severe ditching characteristics than any fixed wing aircraft - BECAUSE of that high CG you cite...they impact, and then turn upside down in the water. That's a fact, and what aviators train to expect. I stand by my statement.

The Starship was 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.

All Starships were leased, not sold - and so Beech simply took them all back and destroyed them. All but one - which belongs to Burt Rutan, who had a hand in the design. His is the only one left flying - I'll ask him about it if I run into him again...I get to about once every few years. His brother's a hoot, too.

Reply to
Rufus

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:

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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.

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

Reply to
Pat Flannery

The V-22 might have its problems, but a Time magazine article should have no influence whatsoever on one's opinions of the merits of a new weapons system.

Mainstream media bias against any and all new weapons systems goes back more than 50 years and is remarkably consistent. The list of weapons systems once criticized as too expensive, too dangerous, too heavy, too big, too fast, too slow, or that allegedly just wouldn't work includes (but is not limited to) the B-52, B-1, B-2, F-14, F-15, F/A-18, F-22, F-111, C-17, AH-64, M-1, and the Nimitz class aircraft carrier. If the mainstream media had made weapons acquisition decisions over the past 50 years, B-29s, F-86s, and Shermans would now be fighting in Iraq.

On the other hand, the media (and the Democrats) once loved Rumsfeld's "light, lean, and lethal" theory of warfare... you know, Humvees with TOW missiles instead of heavy armor. That worked real well.

Ed

Reply to
Modeler ET

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.

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.

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.

Reply to
Rufus

Granted...but that doesn't mean you shouldn't take a look for yourself and form your own opinion.

Reply to
Rufus

Rufus wrote: :> : Bruce Burden wrote: :> Reference, please. It was a fixed wing. It will glide, for :> some suitable definition of "glide", so long as there is air :> passing over the wing and generating lift. :> : : Reference - I'm a degreed aeronautical engineer. The V-22 does not have : enough surface area to sustain a true glide the way a fixed-wing : aircraft can. : Rufus, if you have been on the 'net for any length of time, you should understand why it is bad for to argue from authority. If you are an aeronautical engineer, finding a source that states the V-22 can't glide should be trivial.

The problem we seem to have is that you fundimental view of the V-22 is that it is a helo, my view is that it is a v/stol airplane.

A reference I found on the web indicates that the V-22 can auto-rotate, when in vertical flight configuration, much like a helo. Sorta. Maybe. When configured with the engines horizontal, the V-22 can glide. What I have not found is whether the "normal" aircraft flight controls work when the engines are rotated vertical, or more than around 45 degrees above the horizontal. That cound affect the ability of the V-22 to glide to a landing in an engine failure event.

Since you are a degreed aeronautical engineer, and closely interested in the V-22, finding references should be trivial. : : The possibilities for failure modes are far more numerous compared to a : standard helo...have no idea how they drive the tilt - hyd, electric, : pneumatic...or what systems there are to fail, or cascade failures. : I am well aware that the more complex the system, the more that can and will go wrong. I am also well aware that duplicating systems serves to increase the number of things that can go wrong. The real question is - what is the likelyhood of such an occurance. I deal with chaos theory (specifically, not knowing your precise entry/start conditions) every day. : :>

Reply to
Bruce Burden

he the one with his own graveyard?

Reply to
someone

It damn sure ain't no airplane...and it ain't a helo either - go watch one fly. I just had two in my back yard a few weeks ago.

That's still not a "glide" in the true sense - it's an altered auto-rotation. I still don't buy your source...I'll ask Boeing. I can do that.

No, I'm distinctly NOT interested in the V-22 for engineering and common sense reasons of my own. But that doesn't stop me from knowing people that are.

That all depends on the system, and what it is used for. You want chaos, go study combat survivability.

Double bunk - you obviously haven't seen the crash films I've seen. And yes - it makes a big diff if the props are rotating or not, even for a prop aircraft. That's speaking as a pilot myself.

That is true - but if the only way to get the aircraft to the ground is in pieces, you get a lot of people killed..just like they have been in this thing. And nobody was even shooting at it at he time.

Hey, you want authority, I'll give you authority. And registration and ownership are also two different matters - but I would expect the aircraft to owned by Scaled Composites. Anyway, I still think the Rutan brothers are interesting people.

Reply to
Rufus

...interesting. Our family had it's own graveyard sometime ago. It was the subject of a legal dispute with shopping mall expansion some years back. Turned out after some extensive research that we'd quit-claim to it.

Reply to
Rufus

The aircraft is a real beauty from the aesthetic point of view; but one wonders if the extrapolation of Rutan's concept of canards/swept rear wings doesn't really work in high speed aircraft as well as it did in the VariEze. With the VariEze, he'd come up with everybody's 1950's dream... a low priced, very fuel efficient, stall proof private aircraft with a reasonable turn of speed. Almost a flying motorcycle or Volkswagen.

Pat

Reply to
Pat Flannery

He came and gave a lecture for us once, and as I recall that is still his vision of the future - the ability to commute by air...air-taxi, of sorts; using small light aircraft as a mode of public transportation between short distanced hubs or rooftops.

He's a really interesting guy to listen to, and you can just feel that he's a conceptual thinker far beyond most folks in the room. But if you listen to the guy he starts making sense.

I asked him if he employed many model builders at Scaled Composites - his reply was that if you came to him with an idea, you better be able to build it yourself...so yes - everyone at SC is a model builder.

Reply to
Rufus

Something tells me that getting your license had better be tougher than it currently is. Many folks can't handle two-dimensional maneuvring. I don't think adding another dimension will help them.

Bill Banaszak, MFE Sr.

Reply to
Mad-Modeller

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