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Rollingthunder
14th Apr 2007, 22:18
Seems it's finally getting into full production after 20 years of development. 45 currently with the Marine Corps for training. Untold number of crashes and fatalities. Wanted as a replacement for the Chinook in the middle east initially. Best of luck with it.

pba_target
14th Apr 2007, 22:50
More than that, believe first deployment to Iraq is scheduled for July or so. Having had the pleasure of chatting to some of the USMC guys who now use it, they all love it! Only downside is it is pretty big so can't quite get into the tight spots, but that's not how they're intending to use it anyhow. Seems a good piece of kit when it isnt falling from the sky!

Green Flash
15th Apr 2007, 00:16
As with all step changes in technology, it'll take a bit of bedding-in. Keep the faith peeps. Hope it all works out.

GreenKnight121
15th Apr 2007, 02:12
Not untold, very few for a major change in aviation technology.

The CH-53E had fatal crashes during development also... despite being simply an up-size of the CH-53D.

And that 20 years includes a number of years of very low-level R&D funding, thanks to Cheney's attempt to completely kill it back in Bush 41's presidency.

UNCTUOUS
15th Apr 2007, 02:19
The USMC is expecting to lose one every three years to this unsolvable phenomenon.
I think that they'll find it will be more like one per annum, once four Sqns are fully equipped and combat ready.
Because lateral flight control in the transition to (and in) the hover is via differential collective, once you hit asymmVR there is no recovery....as the analysis of the Marana crash proved. The flick-roll is instant and final.
http://www.iasa-intl.com/imagery/lastsixseconds.jpg

Evalu8ter
15th Apr 2007, 07:28
Unctous, A very graphic representation. However, who on earth teaches their pilots to fly at 350ft/40kts? I hope it was a test profile and not representative of training or aircraft shortcomings. If the USMC are going to fly around using that profile then AVR is the least of their worries....

My friends in the USMC are split on the V-22. Some see it as a transformation in capability and reach, others see it as a touchstone for the future of the Corps. However, others are worried by it's less than helicopter transitioning capability and the lack of forward-mounted weapons (I think the chin turret was removed as a money-saver).

Good luck to the guys in theatre, I hope they succeed in making the aircraft work operationally. It's never easy introducing a new capability, the temptation is to use it like an old one....

JFZ90
15th Apr 2007, 10:44
Interesting AVR pics.

Trying to understand this - does this comes about from a combination of the slow speed & sink rate that effectively puts the rotor in its own vortex and messes with its usual lift? This also effectively limits ability to control lift for long enough for a big diffential to be created from one side to the other - creating a moment / roll that can't be recovered from?

I guess the only answer here is to avoid such a sink rate/forward speed? Is this programmed into the Flight Control System logic (as with carefree handling in other aircraft?) - or are the pilots just trained never to go there? Can you imagine Boscombe trying to certifying this aircraft!

---

Having seen one operate at Farnborough last year - I think it is pretty clear this type of capability is the future (unless affordability issues with the technology render it a bit of a concorde - this shouldn't be the case though). If you look at how often Harriers / Kestrels did unconventional landings (i.e crashed) in the early days, Ospreys development history is not unexpected.

US Herk
15th Apr 2007, 15:00
Bell refers to it as Vortex Ring State - similar to other helos - but this particular problem is unique/compounded to/in the Osprey due to their asymmetric blades when encountering their own downwash at higher sink rates & low forward speeds. The parameters aren't vastly different from most other helos.

Any new aircraft will have problems - designing a new type of aircraft and employing it as a military weapons system with such a radical departure from traditional/conventional configurations is bound to have even more problems.

For the record, 4 crashes (plus a prototype crash) - 26 USMC & 4 contractors KIA.

ProfessionalStudent
15th Apr 2007, 15:47
I'd fly it.

Does anyone know if it is very manoeuvrable in the final stages of an approach (like most helicopters are). If it isn't, then I rescind my initial comment if the bad boys are lobbing stuff at me.

ARINC
15th Apr 2007, 21:41
Some questions from someone with a decidely fixed wing background....

Am I right in thinking only 1 rotor enters vortex ring because the collective is not equal ?

If so can't the collective be ganged and if not why do you need differential collective ?

SSSETOWTF
16th Apr 2007, 05:57
ARINC,

If the real aircraft is like the sim I flew a couple of years ago at Pax there's only one throttle, so I assume the FCS makes the differential collective happen. So the next question is why can't they / haven't they written some control laws to prevent this from happening?

Single Seat, Single Engine, The Only Way To Fly

sharmine
16th Apr 2007, 13:49
http://www.star-telegram.com/238/story/67303.html

Seems so:D

Sharmine

ORAC
10th Aug 2007, 14:47
DefenseNews: Ospreys To Reach Iraq By Ship: Official (http://www.defensenews.com/story.php?F=2956739&C=america)

JACKSONVILLE, N.C. — The U.S. Marine Corps MV-22 squadron heading out for the Osprey’s first combat deployment next month will get to Iraq the old-fashioned way — the Navy.

Marine Medium Tiltrotor Squadron 263 will sail aboard the amphibious assault ship Wasp, a II Marine Expeditionary Force spokesman confirmed Aug. 8. “It’ll save wear and tear on the airplane,” Lt. Col. Curtis Hill said. “This will also allow time to do shipboard integration operations. That will help us down the road as we look to integrate them with the [Marine expeditionary units]."

"The method for returning them has not yet been decided,” Hill said.

The Norfolk, Va.-based Wasp Expeditionary Strike Group is readying for a routine deployment, said Lt. Cmdr. Herb Josey, a Naval Surface Force Atlantic spokesman.

It’s unknown if the Osprey squadron will return with the Wasp. “The method for returning them has not yet been decided,” Hill said.

The Marine Corps Air Station New River, N.C.-based squadron will operate out of Al Asad Air Base during its seven-month deployment.

“The purpose of this is to take these Ospreys to where they can get into the fight,” Hill said. “They will go to a point from which they’ll deploy from the ship.”

VMM-263 includes 10 tilt-rotors and about 200 Marines and sailors. The squadron has been preparing for its combat deployment debut the past several months, doing everything from taking grunts on their first Osprey flights to integration training with other aircraft.

Ospreys will become the Corps’ new troop transport aircraft, flying faster and farther between refuelings than the CH-46 Sea Knight helicopters they’re replacing. There are three operational MV-22 squadrons — VMM-263, VMM-162 and VMM-266 —all based at New River.

The Corps has an inventory of 52 tilt-rotors and should receive another five this year, said James Darcy, V-22 program office spokesman. Next year, 14 MV-22s are scheduled for delivery to the Corps.

West Coast
11th Aug 2007, 06:45
As one argues the merits of the Osprey, the decision must be viewed with regard to the platform its replacing. The -46 is old, restricted (at least it was in peacetime). Many have bullet hole patches from Vietnam.
As far as the chin turret, I believe that's being looked at in a later block. The data should already be there from the USAF I believe.

As Green night mentions, I remember the -53E in its infancy. The aircraft enjoyed a terrible reputation in the eyes of the media yet is now well proven.

Arm out the window
11th Aug 2007, 07:47
Re the asymmetric vortex ring thing - differential collective for control in multi-rotor types is hardly new, being used in the Chinook for pitch, so surely it's not insurmountable.

UNCTUOUS
12th Aug 2007, 02:20
Arm out da Window said:
Re the asymmetric vortex ring thing - differential collective for control in multi-rotor types is hardly new, being used in the Chinook for pitch, so surely it's not insurmountable.
The big difference is that the tilt-rotors asymmVR is out on the end of lateral moment arms. When the Osprey pilot hits asymmVR and a wing starts to drop, his instinctive "pick up the dropped wing" control input embeds the condition even deeper and ensures a worsening snap-roll rate.There is no recovery when you hit the condition. It's always destined to be a repeat of the Marana profile.

US Herk
12th Aug 2007, 02:45
Not to mention the software thinks it's smarter than the pilot. Won't let the pilot "hurt" the aircraft. "Interprets" what the pilot wants based on flight regime. Not atypical of fly-by-wire, but leaves one to ponder if an override feature for some aspects would be desireable.

For example, in a rapid descent where an over-torque would be more desireable than impacting the ground at a rapid rate, the computer won't let you, so you crash instead. Might be a good time to override the max-torque limit of the software.

Navaleye
12th Aug 2007, 04:04
I got to see one in action a couple of weeks ago. Very impressive. Sorry to say it makes the Wokka look so last century. I hope it takes off in every way.

splitbrain
12th Aug 2007, 07:52
As a techie who looks at complicated mechanisms on machines intended for flight with an eyebrow raised, can I just ask what the recovery procedure is should the engines/nacelles fail in their 'forward flight' mode?

ShyTorque
12th Aug 2007, 11:00
"The method for returning them has not yet been decided,” Hill said.
The Norfolk, Va.-based Wasp Expeditionary Strike Group is readying for a routine deployment, said Lt. Cmdr. Herb Josey, a Naval Surface Force Atlantic spokesman.
It’s unknown if the Osprey squadron will return with the Wasp. “The method for returning them has not yet been decided,” Hill said.


I could think of better ways of improving morale...... :hmm:

OFBSLF
13th Aug 2007, 13:46
As a techie who looks at complicated mechanisms on machines intended for flight with an eyebrow raised, can I just ask what the recovery procedure is should the engines/nacelles fail in their 'forward flight' mode?IIRC, the procedure is to do an aircraft style landing on a runway. The blades are designed to break away.

LowObservable
13th Aug 2007, 13:54
Shy,
That was the thought that occurred to me - reminded me of the apocryphal advice from Russian instructors to the Libyans: "Don't worry about the landing - the Israelis will take care of that."

ORAC
2nd Apr 2008, 07:12
Bell Boeing Strategic Alliance Scores Five-Year Contract for V-22 Osprey
Bell Helicopter | Apr 1, 2008

FORT WORTH, TEXAS: Bell Helicopter, a Textron Inc. company, announced today that the U.S. Department of Defense has awarded a $10.4 billion, five-year Multi-Year Procurement contract for 167 V-22 Osprey tiltrotor aircraft to a strategic alliance between Bell Helicopter and The Boeing Company.

"This is a significant step in the V-22 program," said Dick Millman, Bell Helicopter president and CEO. "This five-year contract will allow us to plan much further out as we order long-lead materials, invest for capacity growth, increase our production rate, and deliver these unique aircraft on time to a war-fighting customer who really needs them."

The contract calls for 141 MV-22 aircraft for the U.S. Marine Corps and 26 CV-22 aircraft for the Air Force Special Operations Command. To date, the Bell Boeing alliance has delivered a total of 100 V-22 aircraft to the U.S. military. The Marines currently have 12 MV-22s deployed in combat at Al Asad Air Base in Iraq.

The world's first production tiltrotor, the V-22 combines the vertical performance of a helicopter with the high speed and range of a fixed wing aircraft. The V-22 offers twice the speed, three times the payload, five times the range of the older aircraft it will replace.

Bell Helicopter is an industry-leading producer of commercial and military, manned and unmanned vertical lift aircraft and the pioneer of the revolutionary tilt rotor aircraft. Globally recognized for world-class customer service, innovation and superior quality, Bell's global workforce serves customers flying Bell aircraft in more than 120 countries.

Pegasus#
2nd Apr 2008, 11:15
$10.4bn for 167 V-22s: $62mn each.
Twice the price of a wokka for less than half the payload (pax or USL).
That's a BIG premium to be paying for speed, surely?

Truckkie
2nd Apr 2008, 11:57
Who pilots this wonderful machine? Is it rotary bloke with some fixed wing experience or a fixed wing bloke with some rotary training???

Maybe one of each for each phase of flight???:eek:

LowObservable
2nd Apr 2008, 12:33
$10.4bn for 167 V-22s: $62mn each.
Twice the price of a wokka for less than half the payload (pax or USL).
That's a BIG premium to be paying for speed, surely?

Freedom is the freedom to say that two and two make four. If that is granted, all else follows. (1984)

But there's lots of money and lots of senior reputations riding on the V-22, to shut up and quit mentioning the obvious. WHY DO YOU HATE OUR HEROIC MARINES, YOU :mad:?

Tourist
2nd Apr 2008, 12:41
Pegasus
Depending on the distance you want to go, the extra speed can cancel that out

Evalu8ter
2nd Apr 2008, 18:32
Tourist,
The extra speed will only help if the single load is within the V-22 limit. Think Viking, or CVRT..the V-22 will never lift those in a combat configured state.

However, the USMC happily realise this and are buying the Ch-53K to do the heavy stuff. We must stop comparing the V-22 to the Chinook, it's just as unfair a comparison as Merlin / Chinook (except that V-22 is better than Chinook in a couple of areas.....), compare V-22 to the Phrog and you have a quantum change in capability - speed, range (for proper SToM) and survivability (above the SA/MANPAD environment).

Now, lets let the US iron out the creases and when the unit price drops buy a shed load!! Oh sorry, it might look a bit like a FW but it's still a RW so we'll just buy loads of 9g planks instead.......

AdLib
2nd Apr 2008, 20:34
Pegasus#

Is that a BSW* carrying a BSP" or any wokka in particular? Hint: the devil is in the detail.

* British Standard Wokka
" British Standard Payload

US Herk
3rd Apr 2008, 01:02
Folks really must quit thinking of the V22 as some sort of helo replacement.

It is neither fixed wing, nor rotary - it is what it is. It brings it's own set of capabilities and limitations and is a compromise just as every other aircraft...

wg13_dummy
3rd Apr 2008, 02:27
But more of a compromise of both?


LowObservable, stop being a sensitive cretin.

Pegasus was on about the capabilty v cost not how wonderful your grunts are or are not.

ORAC
3rd Apr 2008, 06:54
Some people seem unable to recognise irony and sarcasm.... :rolleyes:

telecat
3rd Apr 2008, 07:33
This does look like the solution has become too "old" in development. Why not look at how big an Aircraft with two Pegasus engines you could build?? Surely you would get double the speed and increased payload?

Occasional Aviator
3rd Apr 2008, 13:25
Hmmmm... so if you had eight Pegasus engines presumably you could lift as much as a Chinook and travel at about Mach 6 - brilliant!

Zoom
3rd Apr 2008, 14:14
Mach 6 with a decent payload? Now that I like.

Zoom
3rd Apr 2008, 14:22
Any thoughts out there on whether the Osprey concept (2 tilting rotors) is better or worse than the Fairey Rotodyne one (single jet-powered rotor and 2 engines for forward thrust).

LowObservable
3rd Apr 2008, 14:31
Thanks, ORAC...

I was going to respond with the H2G2 line - "They don't have sarcasm on Betelgeuse, and Ford Prefect often failed to notice it unless he was concentrating."

One problem is that the Marines have limited use for high speed. It's only worth the candle if the mission is V-22 alone, because otherwise your escorts and heavy equipment are going at helo speed. That's why special ops - where your limitation is often how far you can get in the hours of darkness, which are determined by Kepler - is an ideal world for the V-22.

Kitbag
3rd Apr 2008, 15:58
This does look like the solution has become too "old" in development. Why not look at how big an Aircraft with two Pegasus engines you could build?? Surely you would get double the speed and increased payload?


Been toyed with in the past, see here:
http://en.wikipedia.org/wiki/Dornier_Do_31

Pegasus#
3rd Apr 2008, 16:32
AdLib:
Fair point: US units (pax and $) throughout, for consistency. Last batch of new-build CH-47s for the US Army were around $34mn IIRC.
I would love to think that we could pay $62mn for our V-22s, but somehow I doubt it. We almost always seem to end up paying the dollar price in pounds.
As for BSP, my concern is the lack of internal volume of V-22 relative to a wokka (BSW or US), especially given the sheer bulk of fully-laden pax on ops.
Anyway, not my money; I wish the Marines well with it (but if it WAS my money, it would still seem a big premium for speed vs. lift).

AdLib
3rd Apr 2008, 21:01
Yes, Osprey is more expensive than Chinook (and unit cost+RAF support vs unit cost+PBL vs lease+little gnomes is a whole other can of financial ZZzzzzz - won't go there).

But Osprey is not a Chinook replacement; it's strengths are speed and range (and it does have a decent payload too). Apply that to (e.g.) MEDEVAC/CASEVAC or CSAR and you have a powerful argument for the platform.

GreenKnight121
4th Apr 2008, 00:25
The MV-22 Osprey is a CH-46 Sea Knight replacement, NOT a CH-47 Chinook replacement.

Please remember the -46 has about 70% of the volume and less than half the cargo lift of a -47.
CH-46D = 25 pax or 2,272 kg internal cargo (3,175 kg total)
CH-47A = 33 pax & 2,720 kg internal (and up to 5,900 kg external)
CH-47D = 6,300 kg internal (10,340 kg external).
CH-47F (CH-47SD) = 12,700 kg on center sling hook or 9,070 kg (18,140 kg total) on each of the two end hooks (fore/aft).

The Osprey's internal cabin & payload are right where the Sea Knight's are... as designed!

LowObservable
4th Apr 2008, 14:11
And speaking of Sea Knight replacements:

http://web.newsguy.com/sather/helo/Boeing360.jpg

http://www.aviastar.org/helicopters_eng/boeing-360.php

Design goal was 200 kt max cruise, and to do the CH-46 mission at a gross weight that was 3,000 pounds less than the empty weight of the V-22.

:{:{:{:{:{:{:{ :mad:!

Occasional Aviator
4th Apr 2008, 17:16
It's not JUST a CH-46 replacement. If you only think of it in terms of a single wave, you're right that the heavy kit can't keep up. But once you start doing really big STOM stuff, it means you can get twice as many men on to the ground in the same time in multiple waves than you could with CH46. And in any case, having some slow aircraft doesn't mean you should never get any fast ones!