V-22 can't autorotate. Say what?

[Revolutionary]

This week's Time Magazine carries an article on the V-22 Osprey which is set to see duty in Iraq this fall for the first time. The article is highly critical of the V-22 program and I was quite surprised to read that apparently the V-22 cannot autorotate in helicopter mode. The author makes a big deal out of this so I don't think it's a matter of a layman misunderstanding the capabilities of the aircraft. As per the article, the V-22 has a dead-man's curve that extends all the way to 2,000 feet and 200 knots (in helicopter mode, presumably). The Pentagon quietly struck the autorotation requirement from the program after it became clear that the V-22 was going to be unable to do it without extensive (and expensive) modifications, citing the relative rarity of dual engine failures.

Granted, there are only a few scenarios possible where a tandem rotor twin would ever need to autorotate but Iraq doesn't strike me as the place where you would want to explore the odds of one of those scenarios unfolding. Anyone here experienced with the V-22?

[ORAC]

Defense Industry Daily article (http://www.defenseindustrydaily.com/v-22-osprey-a-flying-shame-03930/#more) covering the issue.

[Fg Off Max Stout]

I take it that there is a sync shaft so in the event of a single engine failure, the remaining engine can drive both props / rotors (or whatever they are called on this aircraft).

To not have an autorotation capability seems 'unwise' to say the least - can this really be true? Double engine failures are rare but they do happen. I know the crew that autorotated an RAF Chinook to an engine off landing after what was more or less a double engine failure in recent years. It's very 'brave' or foolhardy to believe it will never happen to you. Just wait and see the lawsuits and the mod programs after the first multi fatal crash.

Looking at its short, stubby wings, I bet the glide performance in aeroplane mode is appalling and terrifying. In helicopter mode, even if the blades could autorotate, the empennage would lead to some unusual handling issues and surely a massive nose down moment. Is the Osprey the worst of both worlds, helo and plank, rather than the best?

[nacluv]

"I take it that there is a sync shaft so in the event of a single engine failure, the remaining engine can drive both props / rotors (or whatever they are called on this aircraft)."

It would appear not. After reading the journal article I found the following:

"The Osprey's big problem is that it risks losing lift in just one of its two engines, in which case it will flip over and begin to fall upside down. This has led to previous test flight crashes which were fatal to all concerned."

:(

[BEagle]

You know, I think that the designers probably thought about that.....:rolleyes:

The Osprey can carry 24 combat troops, or up to 20,000 pounds of internal cargo or 15,000 pounds of external cargo, at twice the speed of a helicopter. It includes crosscoupled transmissions so either engine can power the rotors if one engine fails. The rotors can fold and the wing rotates so the aircraft can be stored on board an aircraft carrier or assault ship.

See http://www.boeing.com/rotorcraft/military/v22/docs/V-22_overview.pdf

[forget]

Hardly likely. :hmm:

Also, one engine can power both rotors if required because of a cross-coupling capability.

http://avia.russian.ee/helicopters_eng/bvertol_osprey.php

Beaten to it. :)

Plus - Performance

Service ceiling, ft (m) -- 26,000 (7,925)
Service ceiling, one engine inop, ft (m)
11,300 (3,444)

[c-bert]

This has led to previous test flight crashes which were fatal to all concerned."

What, all concerned? Even the designers and Mrs Miggens whose garden it flew over?

:mad:in' journos.

[airsound]

I believe there is a basic problem with tiltrotors. Either engine can power both rotors if one engine fails (like the Chinook). But because the rotors are on either side, if the power from the rotors gets wildly out of sync, it’s possible for the aircraft to go into an uncontrollabe roll. The so-called Vortex Ring State (VRS) is one way this can happen, and that was what caused at least one of the 3 fatal accidents that have dogged Osprey since it first flew in 1989. That - 18 years - is how long it’s been in development. 30 people died in the three accidents - and in 2000 development was grounded. The Pentagon gave two years for the programme to be sorted out. It was sorted out - basically by restricting the aircraft so that it never gets into that vulnerable corner of the flight envelope. That’s why it now has warning systems for VRS, and improved training for pilots in VRS awareness.

Osprey achieved its successful operational evaluation in June 2005, and the Pentagon approved full scale production in September 2005. Now it faces its greatest test, in operational service.

Btw, I also blinked at what nacluv quotes
The Osprey's big problem is that it risks losing lift in just one of its two engines, in which case it will flip over and begin to fall upside down.
I believe there’s an error there - the report should perhaps refer to ‘rotors’ in this sentence, rather than ‘engines’.

airsound

[ORAC]

That's the problem with selective quotation. The following sentence makes clear the issue and the context:

.....The Osprey's big problem is that it risks losing lift in just one of its two engines, in which case it will flip over and begin to fall upside down. This has led to previous test flight crashes which were fatal to all concerned. As the OT-IIG report states, "When descending at a high rate with low forward speed, the rotor can become enveloped in its own downwash, which can result in a substantial loss of lift. … Should one rotor enter VRS and lose more lift than the other rotor, a sudden roll can result, which quickly couples into a[n inverted] nose-down pitch."

[c-bert]

Sorry chaps but a vortex ring state affects conventional helicopters just as much as Osprey. The only difference is the potential for a lift asymmetry in the V-22.

It's still a very bad day out for any chopper.

[airsound]

c-bert - sorry, I didn't mean to imply that VRS was exclusive to tiltrotors, and I'm aware that it'll ruin the day of any chopper. But, if I've understood correctly (not guaranteed, by any means), the asymmetric aspect has become a virtually insurmountable problem for tiltrotors, whereas conventional choppers manage mostly to avoid the worst results of VRS.

I'm prepared to be corrected!

airsound

[c-bert]

I'm afraid I don't know enough about the project to really comment, other than to say logic implies that VRS is an irrecoverable condition for a tilt rotor.

That said, I'm sure with the advanced control software the thing must have they should be able to prevent/limit control inputs that would allow it to occur.

[LowObservable]

Can someone explain why you'd need to autorotate in a twin-engine aircraft? After all, the 757 that I took from LGW to EWR the other day doesn't have an official two-engine-out mode.

Of course there have been all-engine losses due to fuel tanks inadvertently becoming filled with air, or trying to make the RB.211s breathe volcano dust... but why are helos particularly susceptible?

On the VRS issue, to clarify - all helos are susceptible and it can be serious, but the worst case is that the helo sinks - pilot pours on pitch and power - sink gets worse - pilot says B***er, it's VRS, pushes collective fwd, flies out of vortex.

In the Marana crash, VRS struck first on one side which made the aircraft roll, not sink. Pilot instinctively reacted with opposite stick, but more power/pitch makes VRS worse, so the controls were effectively reversed.

Tactics and training have been changed to avoid VRS - the approach to the landing zone is fast, low, quiet and exploits the fact that the V-22 comes to a rapid screeching halt when the nacelles go vertical. The result is a short slow vertical descent rather than a long descent where the pilot wants to go fast to speed transit through a vulnerable zone.

[Gainesy]

Well the V-22's first combat deployment started today, they left USS Wasp in the Red Sea last night and flew via Jordon to western Iraq.

[ShyTorque]

On the VRS issue, to clarify - all helos are susceptible and it can be serious, but the worst case is that the helo sinks - pilot pours on pitch and power - sink gets worse - pilot says B***er, it's VRS, pushes collective fwd, flies out of vortex.

Really? What exactly happens when you push the collective forward in a helo? :confused:

[LowObservable]

The helo moves forward and leaves the vortex behind. VRS happens in high descent rates when the helo descends into its own downwash, so the trick is to fly out of the downwash column.

[MostlyHarmless]

Now I'm no rotor-head, but if the thing is in VRS and you push the cyclic forward it seems to me not much is going to happen...

...or should I just shut up?

[US Herk]

Not being an Osprey guy, but being posted where the OCU is, I can tell you there's lots of mis-information in this post - to include all articles linked. In fact, too much mis-information to debate singly.

Having been an alternate to field acft as initial cadre (I wasn't selected ultimately), I do know quite a bit about it. Additionally, my best mate out here is one of the contract instructors for the bird.

Some truths:
Can't autorotate - has to do with both aiflow over/through/around the acft AND the engines. One engine can drive both props. Losing the main transmission in an Osprey is just as bad as losing the main transmission in a helo. You quit flying.

It IS fly by wire & the computer DOES think it's smarter than the pilot. Some aspects of flight performance are, in my opinion, adversely impacted by this.

Recovery from VRS is a well-detailed drill in the simulator. I believe, the answer is to push nacelles forward to gain forward velocity, but I haven't done this, so I'm an unreliable source of info. I do know that the controls are what take the most time to get used to - both rotary & fixed wing pilots have bad habits to overcome at critical phases of flight.

OPINION - The lengthy development of the Osprey can be partially blamed on USMC as lead service. There was a GAO investigation about 2-3 years ago that looked at transferring lead service duties from USMC to USAF. Didn't happen. The concern (which I share) was that USMC had no experience developing aircraft. The counter-concern was USAF recent experiences in contracting were fraught with corruption (for lack of a better word).

[ShyTorque]

Low observable, so the drill is to push the collective forwards? Collective controls forward flight? I didn't know that.

[ShyTorque]

Spru, Thanks.

I had a look but after the glaring error in line three of the explanation, I lost interest. :oh:

[Clockwork Mouse]

Cyclic, cyclic, cyclic?

[ShyTorque]

Yes, unless I have been flying under a total misaprehension these last thirty years, I think someone is confusing the control names.

[AdLib]

A more complete explanation, also covering V22 survivability in general:

http://www.globalsecurity.org/military/systems/aircraft/v-22-survive.htm

An excellent site.

[ShyTorque]

Yes, but it over-hypes the advantages of the tilt rotor over the helicopter. Most of the the so-called advantages also apply to helicopters.

Helicopters can also be flown at altitudes where small arms fire is a tiny threat. The SA threat becomes almost negligable at surprisingly low altitudes.

Helicopters can also be given full anti-ice / de-icing protection. The Norwegian Super Pumas flying the North sea have been so equipped for over twenty years.

The tilt rotor will NEVER truly replace the helicopter, except in some specialised (or heavily politically sensitive) roles. It is a specialised aircraft, trading lifting power and low speed handling ability for the "Holy Grail" of a higher cruise speed.

[Revolutionary]

ShyTorque, Spruit's attempt at 'educating' you was downright hilarious! Do they have any idea who you are?

I agree with your point; the tiltrotor concept is in some ways like the autogyro: a courageous attempt at combining the best of a helicopter with the best of an airplane. Sadly, it ends up a compilation of the worst traits of the two modes of flight. Makes you wonder how Bell/Agusta is going to do with their 609. At least it will be able to autorotate. The FAA would never be as cavalier as the Pentagon has been in waiving that requirement. Or would they?

What does the V-22 exactly give the Marines? Speed? Range? Over a short range the Osprey's speed advantage over a helicopter is negligible. And why would they need long range? We're not fighting the USSR anymore. There's got to be a secure airfield within a hundred miles or so of any battlefied, where Marines can get out of a plane and into a helicopter for the last leg of the journey. Nobody likes airport layovers but c'mon...

[Green Flash]

Rev

Agreed. It strikes me that the V-22 is a rather flash answer to a question that doesn't exist (or maybe did exist but doesn't anymore).:confused:

[ShyTorque]

Revolutionary, No matter, I'm only a mere pilot but I've been around for a while; as a pre-flight I do have a look at what folks have on their profile.

I'm still intrigued by the theory that pushing a collective forward gets a helicopter out of VRS. If there's enough adrenaline around, this might result in something interesting - like the grip end of the collective being pushed off.

[West Coast]

Subscribe to OTH warfare and you will understand the importance of the tiltrotor to my brother Marines. The aircraft is going to have further teething problems no doubt, but the concept (if not the aircraft) is a strategic leap in warfare.
Another area is NEO operations. Study even just a bit about the embassy evacuation in Somalia in 1991. The mission was accomplished, despite the equipment available, not because of it.
Even in short range operations there is a large advantage to faster, more capable aircraft. A few minutes may not seem much to an armchair quarterback, but could be the difference between life and death to a grunt in a firefight.

[Evalu8ter]

Gents,
The reason why the USMC is so wedded to the concept of the tiltrotor is indeed range. Not in the traditional sense of invading the USSR, but due to the new "Visions" of Sea Basing and Ship-To-Objective-Manoeuvre (STOM). This argues that, rather than conventional amphib doctrine where you assault a coast, build up combat pwr then strike inland to the enemy centres of gravity you simply fly, direct, to the CoG - thus, the arguement goes, providing shock, dislocation and denial of manoeuvre to the enemy (now removing doctrine bulls**t book from ars*). To go 200 miles plus inland from over the horizon offshore requires a fast(ish), survivable (yet to be proved in the V-22's case) aircraft with good range, hence V-22. But, to deliver the same combat effect in one wave as a Sqn of Ch-53s you're going to need an awful lot of them, or launch the -53s a long time before the V-22s and RV at the IP..
Shytorque, you clearly need to be less subtle in your banter.....

[WE Branch Fanatic]

Can't the V22 put the rotors forward (as in forward flight) and land like a STOL aircraft in an emergency?

[Ian Corrigible]

According to a recent whitespace Bell/Boeing presentation, the current recommended solution for 'busting out' of VRS is to apply 2° nacelle tilt using the maximum (=normal) rate of conversion. IIRC, this results in 400–500ft altitude loss. The V-22 is susceptible to entering VRS at descent speeds between 2000-5000fpm and airspeeds up to 40kt.

Can't the V22 put the rotors forward (as in forward flight) and land like a STOL aircraft in an emergency?
Not all the way forward to 0°, since this would result in proprotor ground strike. The civil BA609 shares the same drawback.

I/C

[Fg Off Max Stout]

Low Observable:
Can someone explain why you'd need to autorotate in a twin-engine aircraft? After all, the 757 that I took from LGW to EWR the other day doesn't have an official two-engine-out mode.

Well I gave a recent example of an autorotation and engine off landing in a twin engine rotary. Your 757 does have a 2 engine out mode - it's called gliding - and it has been useed in anger on large commercial twin jets in recent times. Two examples off the top of my head would be the Airbus the glided about 200 miles into the Azores and the hijacked Ethiopian 767 that ditched off the Comores after running out of fuel.

The point is that double engine failures do occur, often for unpredictable reasons. To design an aircraft that, to use a media term, falls out of the sky following a double engine failure seems unwise to me. Many people owe their lives to the fact that most fixed wing and rotary aircraft can be placed on the ground with a good chance of success following the failure of all engines.

[Two's in]

The V-22 has been evaluated by people who know how helicopters work and hence measure its performance against that. A bit like the British Army's initial evaluation of the Tank by Cavalry officers in 1916. The V-22's eventual operational performance will either save it or kill it.

[Brian Abraham]

Anyone with an interest in the civil requirements for the tilt rotor (Bell 609) will find details here http://www.faa.gov/aircraft/draft_docs/media/BA609%20draft%20cert%20basis.doc

[Revolutionary]

ShyTorque, if pushing the collective forward doesn't get you out of VRS I suppose you could always get out and push the helicopter forward, no?

Evalu8ter, you clearly have a very sophisticated understanding of the modern battlefield (I myself have none) and I can see now where the V-22 would come in handy. Having said that, as Fg Off Max Stout points out, double engine failures do occur. I just cannot understand how the Pentagon could go forward with an aircraft (one meant to carry a whole complement of troops no less) that is unable to deal with this particular emergency. Is it just a waiting game now to see when the first V-22 malfunctions spectacularly?

[US Herk]

You need sinkrates in excess of 1600-1800fpm to enter VRS in V-22. Most aproaches end up with no more than 400fpm sink/flare. At roughly 1000fpm, bitching betty comes on & yells, "sink rate" - should you choose to ignore it, & find yourself entering VRS, a 3-second application of Forward Nacelle & add power to fly out of it results in virtually no altitude loss.

One of the early V-22 crashes resulted because the test pilot kept resetting his master reset & eventually bled all his hydraulics away. The computer analyzes & contains hydraulic leaks through a protocal, but when master reset is iniated, it assumes all is well & must run through the protocal again.
Many of the small problems that are supposed to crop up during DT&E and OT&E have done - the overwhelming majority of them have been fixed.

My understanding of the autorotate deal was compromise. Original design for rotors was actually much larger diameter & sufficient energy was stored in them. In order to accomodate shipborne ops & folding blades, the size was reduced to the point autorotation was ineffective.

Current single engine safe speed is roughly 40-50kts, so you're going to "roll on" (shattering your rotors when you do) with 25-30+ knots of forward airspeed. That's emminently survivable on a hard surface - not so much on an unprepared surface - particularly with a top-heavy beast like the Osprey (probably a lot of tumbling).

Single engine failure in most helos results in arriving at the scene of landing - it merely cushions the autorotation. The same is true of the Osprey. Dual engine failure requires that forward airspeed mentioned in paragraph above.

The Osprey is not, nor was it ever, a helo replacement. It is a different animal entirely. Many USAF brass view it as a Pave Low replacement - it isn't. But those are political problems, not aircraft problems...

[West Coast]

"The Osprey is not, nor was it ever, a helo replacement"

Herk
For the USAF or the USMC? If the later, I might have to disagree. The -46 is long in the tooth. Been a number of years since I've been on one, but the Vietnam bullet hole patches were plentiful. If you're talking about a leap in capabilities far beyond a simple one for one replacement with a newer generation helo, then yes.
One thing you didn't mention in the debate over the lead service was the number of times the program was almost killed by the DoD. Then SecDef Cheney tried on many occasions to end it all. Finally after some open warfare within congress quietly led by Marines operatives Cheney relented. To paraphrase him, "OK, just don't shove them down my throat" The Marines enjoy a tremendous reputation within the beltway, I don't know if the USAF would have the political clout to pull off the mission given the tenuous situation it was having with procurement.
One could also argue, the Marines have as much experience as any of the services in introducing vertical lift in to the inventory.

[Revolutionary]

US Herk, "Dual engine failure requires that forward airspeed mentioned in paragraph above". Do you mean the 40-50 knots? So the h/v curve isn't so big after all? To be sure I understand: let's say you're at 1,500 feet and 100 kts with nacelles up in helicopter mode and at that moment both engines decide to quit. What happens next?

[LowObservable]

Cyclic, collective, schmollective... Jeebus, can't a guy make a mistake? I had been out picking beets on the Agricultural Cooperative No. 541 "V.I. Lenin" and the word was on my mind.

[US Herk]

For the USAF or the USMC? If the later, I might have to disagree. The -46 is long in the tooth.

For both.

It's not a helicopter. Period. End of discussion.

People want to put things in nice neat boxes. Well, there's a new box to put stuff in - tiltrotor.

Yes, the USMC wants to replace the CH-46 because they're old. They bought the Osprey. It will do the -46 mission, but that doesn't mean it's a -46 replacement.

Too much semantics? Perhaps.

Same with AFSOC.

If someone wants heavy rotary lift, buy Chinook.

let's say you're at 1,500 feet and 100 kts with nacelles up in helicopter mode and at that moment both engines decide to quit. What happens next?
First, I doubt you'd be in those conditions. You would be in transition mode with nacelles at some intermediate angle. In which case you'd continue your forward speed to the crash site...errr...landing site.

Most of the approaches occur low & fast with a near immediate stop. There is no long straight down hover. It will terrain-follow in at 100' & 220+ kts, enter approach mode & take a 4* glidepath down to 50'/0kts. If it all goes pearshaped at 50', well, that's how far you fall. A lot of pure helos will hurt themselves from 50' w/no forward velocity as well - simply not a lot of energy stored in the rotors.

Once again, I'm not an Osprey pilot. But we do have a program here where I can fly it - I'm trying to get my stuff in one sock so I can do so. :ok:

[LowObservable]

The V-22 is an attempt to create a helicopter/aeroplane hybrid, just like the Rotodyne, compound helicopters and a myriad of what used to be called "convertiplanes".

The glass-half-full approach is to regard it as both an inefficient helicopter and an inefficient aeroplane. The CH-53E has about the same power and empty weight, and can lift a buttload more stuff. The C-27J is a military cargo aeroplane with the same basic engines as the V-22, has a much greater payload and is faster and has a longer range. And neither needs a 5000 psi hydraulic system.

But if you need vertical capability, the V-22 actually exceeds the performance of the helicopter (range and productivity) once you get past a certain range. In particular, that's why the Spec Ops community loves it and why it works for NEOs. But as a utility trash-hauler, it's really not that much of an improvement over a modern helo. You can try to develop a CONOPS that makes sense, but it's tough (particularly when your heavy-lift and escort aircraft are still helicopters).

And Special Ops is exactly why it exists. If anyone else here remembers, the Marines were happily going about replacing the Phrog (in the early 80s) with a helicopter called HXM. But that was just after the Tehran rescue failure, and people in DC were dreaming of a magic solution that would work next time.

Consequently, people who were, to varying degrees, naive, opportunistic and optimistic invented JVX, which was based on a successful demonstrator and combined SO, Navy (including ASW), Air Force, Army and Marine requirements in a giant program that would (through economies of scale) deliver a tilt-rotor to the Marines for the price of a helo AND lay the basis for a commercial aircraft.

The optimism lay in timing and performance - the real aircraft is much heavier and needs more power/fuel than was predicted at the start, and the initial design was horribly expensive and unreliable. And as time went by and the costs got higher, everyone except SO (who loved it still) and the Marines (who had nailed their colors to the mast) bailed out. And the commercial idea was a load of dingo's kidneys from the get-go.

[airsound]

And the commercial idea was a load of dingo's kidneys from the get-go.
Also - have you heard how much noise these things make when they're in helo mode? Can't imagine them being allowed near city centres with that much racket.

In fact - is that a problem for Special Ops?

airsound

[turboshaft]

What happens next?
In the manufacturer's parlance, a "survivable landing."

AEI in VTOL mode results in a 17° AOA and 4800-5,000 fpm ROD. The aircraft will be written off, but the scenario is considered survivable for the crew & pax.

For AEI in CTOL mode, the V-22 exhibits a 3800-4000 fpm ROD and 160-170 kt descent speed. As previously mentioned, landing at 0° chews-up the V-22’s proprotors (and probably doesn't do the donks & xmsn much good either), but is seen as a preferable to the VTOL scenario.

The V-22's 4.5:1 wing loading is about the same as that of an MD80.

I/C

[ShyTorque]

I maintain if they wanted be there more quickly they would have been better off buying a new large helicopter and setting off a bit earlier ;)

[LowObservable]

The reason that VTOLs like the V-22 have not appealed to the civil market is one of those interesting interplays of engineering and economics...

The idea of a one-pad heliport (like the top of the PanAm building in NY) is an economic non-starter. The traffic is so limited that the service will never be more than Concorde-plus in the narrowness of the market.

So let's make a vertiport with (say) five to ten gates. First off, it's too big for the roof of the PanAm building - it will need some parking as well - and it will have a big noise impact, so it will be off to the edge of town on a brownfield site.

So far, so good...

BUT

This site is now fairly large, several hundred yards from end to end. Adding a short runway does not make it that bigger or more expensive. And even an ultra-short-runway aircraft - with a balanced field length of 2500 feet or so - is a hell of a lot less complicated, more effiicient and quieter than a VTOL. You can get 2500 feet out of a pretty conventional airplane (no cross-shafts or other monkey business).

And it's all so logical that it was thought through this way 35 years ago, in a big US DoT/FAA/industry study, and they actually came up with a spec for a 50-seat quiet STOL airliner, and the Canadians...

http://www.zeco.com/art/press/download-images/hr-dash_7.jpg

... actually built one.

And it was not a great success, but it was the McGuffin that started the idea of London City Airport, and it probably cost less to develop than was spent on the incredibly mendacious campaign for the commercial tilt-rotor.

[ShyTorque]

The Mil Mi-12 was a good example of how aircraft concepts can look good on paper, but flawed in practice. Much larger than anything before or since, with fantastic lift capability, this helicopter was so large that it needed an airport to work from. And the practical advantage therefore, in practice, was - nothing. A fixed wing was more practical. They built two prototypes; it never went into production.

If the tilt rotor can't get into helipads, it needs an airport and then......
I just hope they can get some use for the huge amount of money poured into the project.

[LowObservable]

I just hope they can get some use for the huge amount of money poured into the project.

What are you saying? Engineeers' kids put through college... retired Marines getting well-paid gigs in business development... Fat contributions to Rep. Curt Weldon's campaign...

[Feneris]

There seems to be incessant bitching about every new project, "it doesn't do this, it doesn't do that etc". Osprey, as per every other project is recieving it's criticism. Look at our own (UK) projects, Typhoon, MRA4, Merlin, all over budget, under performing new aircraft. I take my hat off to the designers, engineers and military personnel who've had the balls to design, build and introduce into service something radical and new that opens up new opportunities for commanders in theatre.

As for the points about vortex ring, the ROD figures quoted seem a lot higher than <500 fpm below 40kts that I stick to. Put any troop carrying helicopter into vortex ring and you risk killing all on board.

As for lack of redundancy, all helicopters have the tail rotor drive/control issue, 1 main gear box, as well as the inevitable other little bits that could have been designed better.

As for engine failure, it has 2, it will fly on 1, the chance of a double failure is very remote. Think how often military helo's are in the avoid curve (or 'death curve' as it realistically can be) if they lose 1 of 2 (or 3 engines). Merlin with 3 engines isn't necessarily safe twin, and you may have to ditch or 'cushion the touchdown'. Of course Osprey has it's faults and weaknesses, but so does nearly everything else (especially rotary) that flys. I'd like a go in one!

[US Herk]

I recall the early '90s when C17 was called Buddha. We called it that because it was big & fat, sat around & did nothing, yet eveyrone worshipped it. I was there when they created missions for it so it would have something to do. I recall hearing all of the issues of airdrop (can't drop personnel), short field work (wasn't meeting design spec), etc.

It has proven to be a more capable aircraft than anyone ever dreamed & still isn't being flown to its potential (at least by USAF). It also still has some problems.

The DT&E and OT&E phase of any new aircraft is designed to find flaws so they can be fixed prior to production or deployment. With public access to information, the Internet, mass media, etc. - every flaw is public knowledge and typically latched onto by the nay-sayers & scare-mongerers very quickly these days. Most of these people have an agenda, or at least a bias.

That doesn't mean we produce perfect planes, rather, we have a deliberate process to discover flaws so we might fix them earlier rather than later.

The Osprey is one of the few radical departures from traditional aviation design - as such, it's taken longer to develop. It still has flaws.

Most of the "limitations" on the Osprey or "things it can't do" are history at this point as they stem from early DT&E programs. One of my favorites is that you can't fastrope out of an Osprey. Pure & utter BS - the Osprey has always been able to fastrope troops from the tail - during DT&E they attempted to see if it was feasible out the side door - it's not. This gets twisted by people with an agenda to - "you can't fastrope out of it"

In many respects, you have to un-learn aspects of both rotary & fixed wing employment to appreciate the Osprey. It really is a new category/class of aircraft.

I'm still waiting on the C-model though! :ok:

[Clockwork Mouse]

It has long been a fundamental requirement designed into flying machines of all types that, should things, for whatever unlikely reason, suddenly go quiet, there is an additional option open to the crew and passengers to dying. It would seem that the Osprey does not offer an additional option. You wouldn't find me getting into one, however radical and innovative it may be considered.

[Feneris]

Clockwork Mouse - Ever flown in a modern airliner?? You know, with a nice new fly by wire control system?? Ever worried about a total electrical failure in that airliner?? Maybe you've flown to the USA in a twin engine airliner, did you worry away about a twin engine failure?? I'd much rather be in an Osprey with a double engine failure than in a 777 mid Atlantic.

[brain fade]

I heard the Osprey is a replacement for the aircraft (Herks and H-53) that attempted the Tehran hostage rescue. The one where they all piled up at 'Desert One'.

The idea is an a/c like the V-22 (had they had it at the time) could have:

1. Launched off the carrier- like the H-53s did.
2. Do a long transit with the troops/ 'hostages' in the back without having to refuel (so no herks needed)
3. Do the vertical landing at the hot end and pick up the hostages.
4. Missed out the 'Desert One' scenario altogether.

Who says the military doesn't equip for the last war they fought?

[US Herk]

No - the Osprey is not a replacment for the Herk/H-53. The Iran Hostage Rescue mission, Operation Eagle Claw, is merely the standard they are using to measure performance.

Most proponents of the McRaven philosophy of Relative Superiority and the key element of Surprise suppose that the single biggest risk for Eagle Claw was it required two days to execute. The quest for conducting this type of long-range mission in a "single period of darkness" has been used as the standard to measure the Osprey against.

I suppose it's been applied retro-actively - in other words, we decided we liked the Osprey & tried to figure out how we would have used it in the past.

That's why it's linked to Eagle Claw - not as a replacement for Herks & -53s.

FWIW - It would have required refueling had it done the Iran Rescue Mission. It also would have had to go in much larger numbers than the RH-53s. Part of the problems I alluded to very early in this thread about letting the Marines dictate the dimensions before AFSOC got involved...

Maybe the C-model will be bigger! ;)

[GreenKnight121]

"Part of the problems I alluded to very early in this thread about letting the Marines dictate the dimensions before AFSOC got involved..."


Yes, heaven forbid we let the Marines insist that it fit where they need it to fit, and in the numbers they need.

Everyone knows it is much better to stick with a "let it grow as big as it needs to, then build new (larger) ships to operate it" plan, right?

[US Herk]

Yes, heaven forbid we let the Marines insist that it fit where they need it to fit, and in the numbers they need.
Everyone knows it is much better to stick with a "let it grow as big as it needs to, then build new (larger) ships to operate it" plan, right?

No, you're taking me out of context. :uhoh:

What I said previously, & I'll say again, is Bell approached AFSOC first, but AFSOC could not afford the R&D for the small quantity they would buy & since no one else in the USAF was going to buy them (although I think they'd be a perfect CSAR-X candidate), they had to pass. Besides which, AFSOC gets no money for aircraft themselves - they get MFP-11 money ONLY to modify existing aircraft for the SOF mission.

By the time AFSOC gained approval to pursue V-22, several key design parameters had been fixed in place by USMC. Most painfully for AFSOC (and SOCOM by extension), the dimensions of the cargo compartment - no existing SOF vehicles fit. This is not the USMC fault, nor is it an indictment of that aspect of the program.

This is a common problem for AFSOC (and other SOF units) - not enough buying power due to small quantities & no (or few) separate lines of funding.

For example, the same thing happened with Panoramic NVGs. I tested prototypes in '97, but AFSOC couldn't afford to fund the remaining R&D, so we had to pass. AFRL approached ACC, specifically the A-10 community, who jumped on it. Only after ACC bought enough of them to bring per-unit costs down did AFSOC say they'd get in. They get in at the end though & have to wait for ACC to take delivery of all of theirs first. Oh by the way, ACC keeps adding more & more requirements to them (and rightfully so for their mission) - this is delaying deployment, adding to weight, complexity, & cost and there's no telling when we'll see them...I'd have been happy with the prototypes!! Last I heard, cost was almost four times prototype costs! :eek:

One of the reasons I believe SOCOM should be a separate command - funding. But that's another can of worms! :E

[brain fade]

I saw 3 at Kirtland in August, so I guess the USAF has them too. These will be MV-22 then?

Have to say, they don't 'look right' to me. And you know what they say abput aircraft that 'look right' don't you?:rolleyes:

[US Herk]

I saw 3 at Kirtland in August, so I guess the USAF has them too. These will be MV-22 then?


Would make sense & keep with USAF designating special mission aircraft Mx-xxx, right? Once again, we were a day late & a dollar short. The Marine version is called MV-22 & the USAF version CV-22.

Being career AFSOC, seems backwards to me. ;)

I think they have four here at Kirtland.

[airsound]

Thank you, US Herk, for your knowledgeable and helpful posts.

I wonder if you have a view on something I suggested a few posts ago (#42), that V-22 is so noisy, especially in the hover and transition, that its use as an AFSOC vehicle could be compromised. After all - special operations surely need as much visual and aural stealth as you can manage?

airsound

[Modern Elmo]

Have to say, they don't 'look right' to me. And you know what they say abput aircraft that 'look right' don't you?

“I’m quite sure those V-22 grapes are sour,” said the disappointed fox. “No need for me to try to jump high enough to taste them.”

I wonder if you have a view on something I suggested a few posts ago (#42), that V-22 is so noisy, especially in the hover and transition, that its use as an AFSOC vehicle could be compromised.

.How much quieter is a helo of equivalent size? Answer: not much.

In regard to to the size of the V-22, apparently the USMC specified that it have the same cabin size and folded deck parking footprint as an H-46. In hindsight, the V-22 should have been larger, at least as big as the proposed CH-53K.

[WeekendFlyer]

I had the privelege of a couple of sessions in a V-22 fixed base sim sateside earlier this year, and it was impressive. The PFD goves you LOTS of cues that you may be about to enter a high sink-rate situation and an audible warning if the descent rate gets too high. Also, the nacelles can be tilted quite far forward of the vertical while maintaining adequate ground clearance, which allows short takeoffs and landings to be performed. My background is fixed wing and I found it quite easy to hover. Transition was also a non-event in handling terms, the FCS seemed well sorted.

It seems a lot of people on this thread have criticised the V-22 without actually having had anything to do with it. My advice would be keep your badly informed (or utterly ignorant) comments to yourself. Yes it is expensive, yes it has some unique vulnerabilities due to its unique design, but if a mission needs a VTOL aircraft with long range and high speed transit, it will outperform conventional helos by a big margin. I await with interest reports on how it does in Iraq, and hope it does well.

As for people who think you can get out of VR using collective - I NEVER EVER want to be in a helicopter with you :ugh:

[HeloBeez]

" As for people who think you can get out of VR using collective - I NEVER EVER want to be in a helicopter with you :ugh:"

Try full down collective. Gets you out of VRS every time plank man!

[brain fade]

US Herk

Are you an Osprey pilot (or crewman) then?

I spent two days at Kirtland and never saw one fly!

Be a sport and look in that yellow/ sand CH-53 parked in the middle of the camp, if you have a moment (marked T0013) and tell me which one it is. The tail ramp is open.

Thanks.;)

[Airborne Aircrew]

Gets you out of VRS every time plank man!

Surely that depends upon rate of descent and altitude? So "every time" could be a "plank" statement... :E

[US Herk]

that V-22 is so noisy, especially in the hover and transition, that its use as an AFSOC vehicle could be compromised.
Not any more noisier than a MH-53 or MH-47 really. It's a different sound though.

In regard to to the size of the V-22, apparently the USMC specified that it have the same cabin size and folded deck parking footprint as an H-46. In hindsight, the V-22 should have been larger, at least as big as the proposed CH-53K.
True on all counts.

Are you an Osprey pilot (or crewman) then?
Nope. Talon pilot. But the training command has a programme to allow QFIs to fly other aircraft - I'm going to apply to fly the Osprey. Haven't had the time to sort the details yet.

I spent two days at Kirtland and never saw one fly!
They actually fly quite a bit. There was just a one-time inspection on their blade angle links last week - they were down for a day or so. There was a period last year where they were down for about 2-3 weeks sorting some computer chip issues. Like any new programme, they're cautious & will stand down if there's even a hint of a problem.

Be a sport and look in that yellow/ sand CH-53 parked in the middle of the camp, if you have a moment (marked T0013) and tell me which one it is. The tail ramp is open.

What am I looking for? It was recently moved when they got a J-model Pave to park out front, but still readily accessible. You just want the tail number??

[West Coast]

"Part of the problems I alluded to very early in this thread about letting the Marines dictate the dimensions before AFSOC got involved..."


I also must take umbrage with this. You're either driving the bus or you're a passenger. With comparatively small participation from other services, the needs of the primary user dictate. That said, at least to my rudimentary understanding from a few AD contacts is that the USMC has given ground.

[brain fade]

Herk

Yes, if you don't mind. (there will be a small metal plate in the cockpit somewhere).

Guess I was just unlucky re the flying Ospreys then.

Since you're such a helpful chap would you mind also keepimg an eye out for a HH-60 just marked '58 SOW'. It's tail no is also not known.

Sorry for being such a spotter.;)

[US Herk]

I also must take umbrage with this. You're either driving the bus or you're a passenger. With comparatively small participation from other services, the needs of the primary user dictate. That said, at least to my rudimentary understanding from a few AD contacts is that the USMC has given ground.

Did you read my follow-up to GreenKnight121? Perhaps I phrased it poorly in the latter response (the one you & GreenKnight121 quoted & replied to).

[Opinion = ON] Regardless, and this in no way is a slam agasint USMC at all, letting the Marines run an aircraft acquisition program is akin to letting USAF run an amphibious ship acquisition program. It simply isn't their specialty. Doesn't mean they can't do it, simply means it's highly likely there will be problems. [Opinion = OFF]

Well, there are and have been problems & they're so well documented that the GAO has looked at transferring lead service duties to the USAF despite the disparity in delivered units to each. In the end, they left it to the USMC to sort out. [Opinion = ON] No doubt due to politics.[Opinion = OFF] The USMC carries a lot of clout (and rightfully so) on the hill.

As for the USMC "giving ground" - I'm sure that's how it could be characterized by folks wishing to incite inter-service rivalries, but not how anyone with a bit of understanding of the program would look at it. The intended implication of that volatile statement is that, 'USAF has demanded modifications to the plane & the USMC has acquiesed.' In reality what has happened is the USAF has said, "We want our SOF-specific software to do X, Y, & Z in addition to the baseline." and the USMC has said, "Wow, that's a great idea, let's just make that part of the baseline." This isn't limited to software either. For example, even the chin-mounted gun was never originally required/desired by USMC. Once AFSOC said we had to have one, USMC said, 'you know, that's not a bad idea at all - maybe we should include it in the baseline.' And when that particular poblem gets solved, it will be retro-fitted & added as part of the baseline config.

To date, the overwhelming majority of USAF modifications/upgrades to CV-22 have been retro-fitted to V/MV-22 baseline by USMC as lead service, not because of inter-service demands, but because the mods make sense. This is why many believe DoD would be better off if USAF was lead service because many of the mods that were integrated into baseline after USAF "demands" fell into the "Gee, why didn't I think of that?" category.

Again, much of this falls into the designed DT&E/OT&E function of identifying discrepancies & their corrective actions - where USAF experience (good & bad) pays dividends.

[HeloBeez]

" Gets you out of VRS every time plank man! Surely that depends upon rate of descent and altitude? So "every time" could be a "plank" statement..."

I only said it would get you out of VRS, I didn't say it would keep you from hitting the ground. I maintain the assertion. Full down collective will ALWAYS get you out of VRS. This may or may not be a good thing, depending on other factors.

Beez

[West Coast]

"the Marines run an aircraft acquisition program is akin to letting USAF run an amphibious ship acquisition program. It simply isn't their specialty"



Perhaps I didn't take the post in the tone intended. That said, you might want to check who does the procurement of amphibious ships. While the Marines have input, that bus is driven by the Navy. Spend some time on a LHD sized ship and you'll find plenty of unwanted compromises.

To the above, no it's not their specialty, but it's an aircraft that is largely intended for the Marines use. Dove tailing nicely to that, The bulk of VTOL experience within the military resides with the Marines.
The tail shouldn't wag the dog, I would hate to see the USAF run the program and have something the largest user doesn't want foisted upon them, an Air Force aircraft adapted (another word for compromised) for the Marines use. The Navy and the F111 come to mind.
Who else in the US military has the experience the Marines do in unconventional aircraft and vertical lift as the Marines? The Harrier 2.0 (F35) experience shows no particular brain trust within the USAF in that direction.
You're correct about the significant power the Commandant can focus on the hill, as evidenced simply by the Osprey's continued existence. I however have to believe the reason the program remains with the Marines is the unique nature of the aircraft, and as you mentioned, the procurement scandals within the USAF.

Perhaps the F35 program should be handed over to the Marines and the RN?

[GreenKnight121]

The MV-22 already has a take-off footprint as large as a CH-53E... making the aircraft the size of one would make the T/O footprint so large it would severly degrade deck ops on an LHD... and make operating from a Whidbey Island class LSD nearly impossible. A San Antonio LPD... yes, but only one vs the 2 they can now operate.

The MV-22 is the size it is in order to allow it to fly from the ships the USMC needs it to fly from, in the numbers they need... something your "should be" version couldn't.


There have been proposals for a larger tilt-rotor (using 4 of the MV-22 engine/rotors on two wings), with a CH-53K-like cargo and troop capacity... I believe this should be pursued, but they could only visit LHDs... not be normally operated from them.

[US Herk]

My intent isn't to poke fingers in eyes, yet that is how it seems to be taken.:sad:

Many folks have commented on size. As both of you point out, it is that size because of the initial design parameters established by USMC. Had AFSOC been in a position to begin the program, it would have been a different size.

As mentioned, AFSOC has no money to pursue acquisition of aircraft & even if they did, the small numbers would dictate even higher per-unit costs. The MFP-11 money used by SOCOM to modify service items (vehicles, aircraft, weapons, etc.) means that AFSOC takes standard items (C-130) & makes special mission variants (MC-130, AC-130, etc.). So we adapt the MV-22 to CV-22 & accept compromises. That these compromises, which are out of AFSOC's control, are now points of contention with Osprey critics seems to be lost on some...:ugh:

My assertation that USAF should do the acquisition lies with experience & specialty. If it were a rotary asset shared jointly, I would say USA has the lead. Anything on the water, USN/USMC. Fixed wing, USAF. Osprey is unique - current DoD VTOL experience does indeed lie with USMC Harrier program. Special Mission experience most definitely lies in SOCOM & the air component of SOCOM is AFSOC. The Osprey is more than just VTOL & I would argue that Harrier VTOL is apples & oranges with Osprey VTOL & aligns more with special mission. But SOCOM doesn't do major acquisition, so we're back to square one - which service? I stand by my guns that USAF should do acquisition of Osprey & it is precisely the lack of experience in major aircraft acquisition by USMC that has caused some of the problems - put your hackles back down, this isn't a slam on USMC.:)

I'm sure there would be many concerns over big user (USMC) vs small user (USAF) with oversight/control, but that, I believe, is easily rectified with Joint acquisition & carefully delineated acquisition requirements. Maybe I'm too optimistic...:ok:

As for unconventional aircraft & vertical lift - as soon as you mention the term unconventional, we need to start defining things. My definition (all subject to my own personal biases) is SOCOM = unconventional. I'm sure yours is quite different. Such is the nature of discussions - we each enter with our own personal biases colored by our experiences. There is very little that is right/wrong, black/white, rather, best for a given situation - hence our different points of view. It'd be much simpler, yet very boring, if we all thought exactly the same way! :)

Of course, all of this would be much easier over a beer...:ok:

[West Coast]

"Of course, all of this would be much easier over a beer"

A man after my own heart.

Yes, FAR part one, definitions. At least as defined by me. Unconventional for purposes of this discussion is meant to describe the aircraft not the mission. Though somewhere the two cross.

"Had AFSOC been in a position to begin the program, it would have been a different size"

Agreed. However had the design been locked in larger or smaller driven by AFSOC needs, IMHO the Marines wouldn't have signed on but rather pursued a traditional rotary wing replacement for the phrog. Where would that have left a small component of the USAF? Again, my opinion, but Cheney would've successfully canceled the program in it's nascent stages. Something he tried but failed to accomplish.

A clean sheet medium lift transport is a utility player while an aircraft designed for special forces is a position player. (I know these sports analogies drive the Brit's looney) That said, the US military has a wealth of experience in converting trash haulers to suit the needs of special forces. Yours is the first that comes to mind, many others follow. How many special forces aircraft have been adopted for utility roles? Not going to say none, but I'm hard pressed to come up with one. I'm hard pressed to even name a major aircraft acquisition driven by the needs of any special forces component of any branch of the US military. It's late at night so there may be some escaping my fallible memory.

The Marines need a utility aircraft designed for their needs, not one compromised from a special forces application. An aircraft equally at home hauling Marines into a LZ, landing in a CAL site or maneuvering around the deck of a LHD. The AFSOC surely thinks the same, but the Marines are the ones who had the political wherewithal to power it from a paper airplane, through painful crashes, political turf wars and now to fruition

Either one camp or the other is going to feel overly compromised. The question is which operator is more able to work within those compromises.
I've made my argument as to why it shouldn't have to be the Marines.

I'd be interested to see the views of the other bit players who plan to or contemplate operating the aircraft.

[US Herk]

How many special forces aircraft have been adopted for utility roles? Not going to say none, but I'm hard pressed to come up with one. I'm hard pressed to even name a major aircraft acquisition driven by the needs of any special forces component of any branch of the US military. It's late at night so there may be some escaping my fallible memory.


How many? I'm pretty sure you're right - none. Because of their specialization, the numbers remain too small for economic viability.

The closest you get is pure programs vs evolutionary programs. For example - Talon II vs Talon I. Talon I was evolutionary - the penetrating infiltrator mission did not require much sophistication in the mid-'60s. As IADS evolved, so did requirements, and more equipment was bolted on as new missions & programs (Skyhook, Heavy Chain, Combat Spear/Knife/Arrow, etc.) - even the days of the old "Jungle Jim" program where individual unit commanders had access to funding to modify aircraft as they deemed fit led to a variety of Combat Talon I configurations until Mod-70, then Mod-90 standardized them all (mostly).

Talon II was the first infiltration platform designed with that mission in mind - everything is integrated.

Still, we bolted stuff onto a utility aircraft - the C-130. And while there are pure programs & evolutionary programs, there are also hybrid programs (Pave Low comes to mind) combining aspects of both...

Blah, blah, blah (more of my non-pertinent blather) - you make a good & valid point so long as money drives the boat. Which, invariably, it does. If mission drives the boat, you have to clean-slate everything.

I go back to my assertation that SOCOM should be its own service! :E

However had the design been locked in larger or smaller driven by AFSOC needs, IMHO the Marines wouldn't have signed on but rather pursued a traditional rotary wing replacement for the phrog. Where would that have left a small component of the USAF? Again, my opinion, but Cheney would've successfully canceled the program in it's nascent stages.

They did - CH/MH-60! But apples & oranges to some extent - my position is that had AFSOC (nee, USAF - AFSOC didn't even exist back then, it was 23rd AF & pre-Nunn-Cohen/Nichols-Goldwater too!) been driving the boat, it wouldn't have been fraught with as many problems during acquisition, DT&E, etc. Cheney may not have tried to kill it! :E But that assumes USAF would have handled it better than C-130 AMP, KC-X, CSAR-X, etc. An argument could be made that it would've come online quicker too...before all our embarassing scandals. :ooh:

But when I say it would be bigger if AFSOC had been lead, I don't mean hugely bigger - actually it only needs to be slightly bigger. It might still fit within the footprint of the -46. The width of the cargo compartment is the main limiting factor - it's only about 5' (don't have exact figures handy) wide. Nothing fits.

Nothing fits because it was optimized to carry troops, not cargo, but 20 years is a long time ago - I believe USMC is now wishing it were wider so they could transport expeditionary fire support stuff. ;)

The Marines need a utility aircraft designed for their needs, not one compromised from a special forces application. An aircraft equally at home hauling Marines into a LZ, landing in a CAL site or maneuvering around the deck of a LHD.

I think an AFSOC-designed Osprey would do all of that. But who knows what really happens if they were given the blank sheet of paper to start from...
I say crank up the CH-60 program - open the tap. Transport troops with that & make the Osprey haul cargo - that would require fuselage redesign - completely unfeasible at this point. But then USMC could play more in SOCOM...:)

Amazing what 20 years of hindsight reveals!

One more tidbit that goes back to experience/expertise - KC-130J. USMC bought KC-130J w/o software upgrades. "We'll take version 1.0 software, thank you." :confused: Also bought w/o much of the support USAF demanded (training, tech manuals, simulator, etc.) - just the plane & a couple spare parts. I know the Marines are experts at "making do" with what they've got in austere conditions - it's why they're so good at what they do - but why start off half hamstrung?

I'm rambling again...

Sorry for the disjointedness - trying to stay up late so I can fly a late night sortie tomorrow, but the body/mind isn't cooperating! :O:zzz:

[Jake39]

I had direct contact with the V22 in the early 1990's . With Sundstrand systems. The problem we ran into transferring power from one engine to the other was electrical relays closing fast enough to transfer power with out the loss of control.

Imo, maintenance on this vehicle would be a nightmare aboard ship..

I remember discussions about the vehicle maintenance on the hanger deck would be impossible because of the height limits below deck.

Have they addressed this?

[GreenKnight121]

They have addressed a lot of things since you were around it.

There are now more USMC medium-rotary squadrons equipped with MV-22 than CH-46F, and they have been deploying aboard the Wasp-class LHDs and for a couple of years now.

Both the USMC and USAF have conducted repeated deployments to Iraq & Afghanistan with Ospreys.

[v22mech]

If any of you know about the 46 understand the main roles that this aircraft was assigned was troop insertion and medivacs. The main point that should silence anybody in regard to the validity of service of the V22, is the great impact this aircraft has on the golden hour hour for wounded personnel. There are many areas that this aircraft helps area commanders is first the increased area that he can control due to increased range. Second it allows for freedom of assets due to its increased speed its able to refuel at the same time as an F/A-18 therefore There's the removal of transition time between refueling and the ability to few two different aircraft that may have entered a critical level while waiting for deconfliction. Those who say that the USAF should have had the lead on the aircraft might be suprised to learned that they surrendered lead to the Marines realizing that this was an aircraft suited to them. The airforce has stayed on through all aspects of test and eval. Of the aircraft to include testing at Nellis airforce base. Its easy to cast stones based on info spoon fed to you. It's a lot harder to research and form an intelligent opinion.