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V22 Osprey discussion thread Mk II

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Old 2nd Jul 2012, 13:50
  #221 (permalink)  
 
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four MV-22s were scheduled to fly from North Carolina to England to take part in two international air shows
Sitting here in FSI FAB looking out of the window at them!
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Old 2nd Jul 2012, 18:00
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Sitting here in FSI FAB looking out of the window at them!
S-92 sim training at FSI?


Last time I was at Farnborough was the first time the Osprey came to visit (2006?)...
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Old 6th Jul 2012, 17:34
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The V-22 / Bin Laden Connection

Posted by Amy Butler 2:42 AM on Jul 06, 2012

Bell/Boeing is starting an aggressive international sales push for its V-22 tiltrotor at the Royal International Air Tattoo in Fairford today.
The U.S. Marine Corps has brought four of the Ospreys, which takeoff and land like a helicopter but can fly up to 300 kts like a fixed-wing aircraft, to RIAT. And, they will be on static and flying display next week at the Farnborough air show.
The history of the V-22 is well known; the tiltrotor has survived many attempts by defense secretaries to kill it owing to four crashes in its protracted development. Though the aircraft has recently proven itself during deployments to Afghanistan and Iraq. And, an MV-22 based rescue of an F-15E crew downed in Libya got the attention of the United Arab Emirates, which is eyeing the CV-22 version for its military. Israel and Canada are said to be interested as well.
But, a little known tidbit has been circulating in the Pentagon that will add to the V-22’s credo – according to some – and notoriety – according to others. After U.S. special forces raided 9/11 mastermind Osama bin Laden’s compound in Pakistan last year, a CV-22 was used to transport his body to the USS Carl Vinson. Onboard the aircraft carrier, officials prepared the body for a burial in the North Arabian sea. Pentagon officials said no nation was willing to accept the remains.
It is notable that the MV-22 only recently conducted trials on a U.S. aircraft carrier. Because the CV-22 was designed for transporting special operations forces, this aircraft has likely been used on decks and instrumental in covert missions for some time.
The Pentagon is buying 360 MV-22s for the Marines; 53 CV-22s for U.S. forces and, potentially, around 50 for the Navy.
Despite some notable operational achievements, the Bell/Boeing team will have to address concerns from customers about the high cost of the aircraft. Pentagon officials put the per-unit price at $67 million, though they say the cost-per-flying-hour is coming down. Company officials often say the price of the aircraft is balanced by its operational flexibility owing to a mix of speed and vertical lift.
Aviation Week & Space technology
The V-22 / Bin Laden Connection
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Old 7th Jul 2012, 21:37
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Breaking news - quasi helicopter has landed on aircraft carrier! What next - men on the moon?
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Old 7th Jul 2012, 22:19
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Trash haulers....always putting on airs!

Granted that particular piece of trash would have been a pleasure to haul out to sea knowing it was a one way trip for it.
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Old 8th Jul 2012, 02:03
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SAS, 212

The V22 had the range and speed for the escort fighters to escort it out.

One more thing it did three things a Canadian H92 can not do:

Fly at night

Fly over water

Land on a ship

And seeing that 50% of the Sikorsky products crashed before the action started the Osprey was the best choice to actually complete the mission.

TC
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Old 9th Jul 2012, 17:28
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C21 - Note, the reporter in question subsequently corrected herself, confirming that the aircraft used was indeed an MV.

I/C
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Old 9th Jul 2012, 17:37
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Thanks I/C,
Post deleted on 'CV vs. MV' until confirmed. Do you have a link on the correction? Will check other sources.
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Old 9th Jul 2012, 17:57
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Here you go: The V-22 / Bin Laden Connection (scroll down to second comment)

I/C
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Old 9th Jul 2012, 18:44
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Thanks for that I/C, that does verify her correction in the AWST post-comments. The original claim that it was a 'CV-22' and not an 'MV-22' that gave significance to the article appears to have been withdrawn. Will advise if any corrections to that are heard.

There are another couple of minor errors she made that are not yet corrected in post comments. The reporter was correct that 'the Navy never cancelled its order,' but quotes that are 'not quite there' are when she says they have on order, "potentially, around 50 for the Navy," and "53 CV-22s for U.S. forces." It is actually 48 for the Navy and 50 for the USAF (SOCOM).
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Old 9th Jul 2012, 19:31
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Its also nice to see our old friend mud-slinger Carlton Meyer sticking his nose into blog post comment sections in his long standing attempt to sway public opinion against the Osprey.

Posting as "carlo" and pasting a link to his G2mil site is about as unabashed as it gets.
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Old 9th Jul 2012, 19:37
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Thanks I/C, it has been externally verified that it was an 'MV-22' and not a 'CV-22' that carried the body of bin laden to the USS Carl Vinson...

As Sas would say, it looks like the Marines 'took the trash out...'
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Old 10th Jul 2012, 05:30
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Safety top priority for Osprey operation in Japan: Clinton

Kyodo
U.S. Secretary of State Hillary Clinton on Sunday pledged to ensure the safe operation of Osprey military aircraft to be deployed at a base in Japan later this year, suggesting there is no change in Washington's schedule for the transfer, despite strong local opposition.
Foreign Minister Koichiro Gemba said at a joint press conference with Clinton after their talks in Tokyo that they will speed up the ongoing realignment of U.S. military forces in Japan to produce some positive results "by the end of this year."
Gemba and Clinton agreed to stick to the two countries' plan to relocate the U.S. Marine Corps' Futenma Air Station within Okinawa Prefecture, from a residential area in Ginowan to the less densely populated Henoko district of Nago, a Foreign Ministry official said, although a majority of local people are hoping for the air base to be moved outside of the southwestern island.
Gemba and Clinton also said they will continue to cooperate on issues related to maritime security, Afghanistan, North Korea, Syria and Iran, among other topics.
Gemba said he conveyed the concern in Japan over the deployment of the MV-22 Osprey transport aircraft at the Futenma base following recent crashes in Morocco and Florida, while Clinton promised to share all necessary information with Japan once the results of investigations on the accidents are ready.
"The United States cares deeply about the safety of the Japanese people," Clinton said. "We will work closely with our Japanese partners to make sure that any American equipment in Japan will meet the highest safety standards."
But she suggested the United States has no plans to change the schedule for the tilt-rotor aircraft's deployment to replace the aging CH-46 helicopters currently at the Futenma base.
Clinton said the MV-22 Osprey has "excellent safety records" and the replacement will "significantly strengthen our abilities in providing for Japan's defense and performing humanitarian assistance, disaster relief operations and other duties as a key ally."
A civilian cargo ship carrying MV-22 Ospreys has already left the United States and is expected to arrive at the Marine Corps' Iwakuni Air Station in Yamaguchi Prefecture in late July, before the deployment at the Futenma base. A ship believed to be carrying the planes left Hawaii on Saturday for Japan, according to a Japanese peace group monitoring the U.S. military.
During the one-on-one talks on the sidelines of an international conference on Afghan development in Tokyo, Gemba and Clinton discussed some economic issues as well.
As part of efforts to strengthen bilateral economic ties, Clinton said the United States "welcomes Japan's interest" in a new multilateral free trade accord, called the Trans-Pacific Partnership.
Gemba and Clinton will both attend a regional security forum in Cambodia next Thursday. Territorial disputes in the South China Sea are expected to dominate discussions at ministerial meetings of the Association of Southeast Asian Nations and its dialogue partners in Phnom Penh.
Gemba and Clinton said the two countries are hoping to see progress on crafting a regional code of conduct to reduce territorial and maritime conflicts in the South China Sea.
On the sidelines of the ASEAN meetings, Clinton said the United States, Japan and South Korea will hold a trilateral meeting, during which North Korea's nuclear program is expected to be a major agenda item.
Before meeting Gemba, Clinton also held a brief meeting with Japanese Prime Minister Yoshihiko Noda in which they reaffirmed their commitment to working closely on bilateral issues as well as regional challenges in the Asia-Pacific region, according to Foreign Ministry officials.
Safety top priority for Osprey operation in Japan: Clinton | The Japan Times Online
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Old 10th Jul 2012, 19:32
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Carlos back and apparently he still hasn't bothered to learn a thing about aviation or the V-22.
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Old 10th Jul 2012, 20:59
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Well here you have it

Marines Peg 'Bad Flying' As Cause of April V-22 Crash in Morocco

Marines Peg 'Bad Flying' As Cause of April V-22 Crash in Morocco

By Richard Whittle
Published: July 9, 2012

An April 11 MV-22B Osprey crash in Morocco occurred because the pilot committed a fundamental flying error which investigators have found was rendered irreversible by a tailwind neither he nor a second pilot in the cockpit noticed, AOL Defense has confirmed.

The Defense Department announced June 29 that the Marine Corps had ruled out any "mechanical or material failure" in the accident, in which two Marines were killed and the two pilots were injured.

"This wasn't a tiltrotor accident; it was bad flying," said a government source with detailed knowledge of the findings, which are still being reviewed by Marine Corps leaders.

Two military officers familiar with the findings separately confirmed that the pilot of the mishap aircraft started the sequence of events that culminated in the crash by violating an explicit instruction in the Osprey's flight manual.

"No-kiddin' human error is involved here," one military officer said. Another said of the pilots: "Unfortunately they put the aircraft in a position beyond the (flight manual) limits that are advertised and that are trained to, and they made an error."

The Osprey, which can carry as many as 24 troops loaded for combat, is called a "tiltrotor" because it points two large rotors housed in wingtip pods called "nacelles" upward to take off and land like a helicopter and swivels them forward to fly like an airplane. The ability to tilt its rotors gives the Osprey far more speed and range than conventional helicopters without a conventional fixed-wing airplane's need of runways to take off and land.

The MV-22B that crashed in Morocco was attached to Marine Medium Tiltrotor Squadron 261 (VMM-261), based at Marine Corps Air Station New River, N.C. VMM-261 was participating in a joint military exercise with Moroccan armed forces when the accident occurred.

Just prior to the accident, with the less experienced but fully trained copilot at the controls, the Osprey had set down helicopter-style to drop off at least the second load of troops its crew had delivered that day to the same austere landing zone. As the pilots took off to return to a temporary on-shore base, the following events unfolded in quick succession:
Under a clear, daylight sky and with no dust interfering with the crew's view, the pilot at the controls lifted the Osprey into a hover 20 or 30 feet above the ground with the plane's nose pointing into the wind, as it had been when the aircraft landed a few minutes earlier.
The pilot flying then used his foot pedals to turn the Osprey in a half-circle to the right, rotating in mid-air to head in the direction from which they'd arrived. As the aircraft turned, it climbed to about 50 feet.
As the Osprey turned, the pilot pitched the aircraft's nose down about 10 degrees by pushing the control stick forward with his right hand. At the same time, using his left hand, he turned a small thumbwheel on the Osprey's throttle, or Thrust Control Lever, to tilt the nacelles and rotors down from 90 degrees and brought them to an angle significantly less than 75 degrees – a position that violated flight manual limits on nacelle angles at low forward airspeed. The effect was to shift the Osprey's center of gravity too far forward, causing the nose to plunge downward.
As the nose went down, the pilot was unable to hold it where he wanted by pulling back on the control stick because the horizontal stabilizer at the aircraft's tail was being pushed up and forward by a 20-knot tailwind. The tailwind's speed and direction were depicted on a digital map inside the cockpit, but vegetation in the area was too sparse to alert the pilots to the wind as they looked outside the aircraft during takeoff. The tailwind pressure on the horizontal stabilizer reduced the stick's "aft control authority" while adding downward leverage on the nose. "By the time the pilot realized he was out of back stick authority, it was too late," one source observed.

The aircraft plunged nearly straight down into the ground, hitting nose first. The cockpit was crushed, but the two pilots – whose identities haven't been released – were strapped into their seats and survived, though with severe injuries. The two enlisted crew chiefs, Cpl. Robby A. Reyes, 25, of Los Angeles and Cpl. Derek A. Kerns, 21, of Fort Dix, N.J., were killed. MV-22B crew chiefs, like those on Marine Corps helicopters, ride in the back cabin and often stand during flights, secured only by a long strap attached to the aircraft to keep them from falling out if the back ramp is open.

Despite being loaded with more than half the fuel an MV-22B can carry, the Osprey didn't catch fire after crashing, and its Crash Survivable Memory Unit, or "black box," was recovered. The CSMU, which records aircraft operating data, showed conclusively that there were no mechanical problems with the aircraft.

"Flight data information indicates that the aircraft performed as expected and described in the MV-22 Naval Air Training and Operating Procedures Standardization (NATOPS) Flight Manual," the Defense Department's June 29 news release said. "The U.S. Marine Corps has determined the aircraft did not suffer from a mechanical or material failure and there were no problems with the safety of the aircraft."

Additional analysis determined that the combination of the pilot violating the NATOPS limit on forward nacelle angle at low airspeed, the resulting excessive forward center of gravity and severe downward pitch of the aircraft's nose, and the tailwind pushing the bottom of the horizontal stabilizer as the tail of the aircraft angled upward all contributed to the crash.

"The combination of those factors made the aircraft unrecoverable at low altitude," one source said. "Below 40 knots calibrated air speed, there is insufficient wind moving across the conventional airplane control surfaces to add roll, pitch or yaw control authority. The aircraft relies on the controls of a helicopter."

A helicopter's controls change the craft's position by changing the angle at which its rotor blades hit the air they're moving into, known as the "relative wind." An airplane's controls change the angles at which control surfaces such as elevators and ailerons hit the relative wind. The helicopter-airplane hybrid Osprey's computerized flight controls work like a helicopter's at slow speeds and like an airplane's once a V-22 gains enough forward air speed for its wing to produce more lift than its rotors -- usually 110 knots or more with the wing horizontal. At nacelle angles between 75 and 30 degrees, the Osprey's flight control computer blends helicopter and airplane controls.

Despite those characteristics, veteran Osprey pilots said the root aerodynamic cause of the Morocco accident wasn't peculiar to a tiltrotor.

"As with any aircraft, there are center-of-gravity limitations," said a pilot who agreed to discuss the crash on condition of anonymity because the results of the investigation have yet to be released. "Too much forward center of gravity in any aircraft, the aircraft will not have enough pitch authority to counter the nose-down pitching moment. Too much aft center of gravity and the aircraft will not have enough pitch authority to counter a nose-up pitching moment."

Contrary to at least one report, the crash in Morocco had nothing to do with a well-known Osprey peculiarity known as Pitch Up With Side Slip. Aerodynamically, what happened in Morocco was the direct opposite.

In Pitch Up With Side Slip, the downwash from the rotors of an Osprey flying at a slight angle into relative wind of 20 to 30 knots, or hovering with a front quartering wind of 20 to 30 knots, can push down on the horizontal stabilizer at the tail, pitching the aircraft's nose up. Osprey pilots are trained to compensate for Pitch Up With Side Slip by pushing the control stick forward a bit or turning the aircraft's nose directly into the wind. The Osprey's computerized flight controls also automatically compensate for Pitch Up With Side Slip by tilting the nacelles forward a touch when necessary.

The pilots in the Morocco crash could face penalties, depending on the findings of a Judge Advocate General Manual (JAGMAN) investigation, whose purpose is to assess responsibility, and a separate Field Flight Performance Board review, whose purpose is to determine whether the flight crew are fit, motivated and worthy of continuing to fly. The flight performance review isn't complete. Marine leaders are reviewing the findings of the JAGMAN investigation as well as the report of an Aircraft Mishap Board, whose role is to assess safety lessons or issues raised by an accident and whose evidence is privileged and never released.

The Flight Characteristics chapter of the MV-22B NATOPS manual contains several sections relevant to the crash in Morocco, including one "Warning" -- a designation used to highlight risks that can lead to injury or death.

The Warning cautions pilots that "severe pitch down and altitude loss can occur if nacelles are rotated too far forward too quickly at takeoff."

A separate note advises that when accelerating by tilting the nacelles forward, an Osprey pilot should apply "aft stick movement to maintain pitch attitude due to thrust and cg (center of gravity) effects."

The Operating Limitations section of the NATOPS manual explicitly instructs: "When transitioning to forward flight from a hover, limit nacelles to greater than 75 degrees until 40 KCAS (Knots Calibrated Air Speed) is reached."

The Defense Department issued its unusual June 29 statement about the Morocco crash because the Marine Corps has long planned to deploy the first of two 12-aircraft squadrons of Ospreys to Okinawa this summer. The MV-22Bs are to replace CH-46E Sea Knight and CH-53D Sea Stallion helicopters based at Marine Corps Air Station Futenma.

Local officials on Okinawa, where a CH-53D crashed in 2004, injuring three Marine crew members but harming no civilians, have expressed concern about the Osprey's safety record in the wake of the Marine Corps crash in Morocco and the June 13 crash of an Air Force CV-22B at Eglin Air Force Base, Fla. The CV-22B accident, which occurred during a training flight, injured the crew of five and destroyed the aircraft but killed no one.

AOL Defense has previously reported that in the CV-22B crash, still under investigation, one possibility being examined is that the pilots flew closer to an Osprey in front of them than the prescibed separation of 250 feet. Under such circumstances, turbulence created by the rotor downwash of the lead Osprey can knock the lift out from under one rotor of a trailing V-22, causing the aircraft to roll suddenly in that direction. At low altitude, such roll offs can be unrecoverable.

After being briefed on the findings of the investigation into the Morocco crash, Japanese officials agreed to allow an initial squadron of Ospreys to be shipped to Marine Corps Air Station Iwakuni on the Japanese mainland for eventual deployment to Okinawa. In exchange, the United States pledged that no V-22s would fly over Japan until the findings of investigations into the Morocco and Florida crashes are made public.

The June 29 DOD statement also emphasized that Marine and Air Force Ospreys would continue flying elsewhere in the world, and four MV-22Bs are at this week's Farnborough International Airshow southwest of London to provide demonstration rides to potential foreign buyers. The Naval Air Systems Command and the Osprey's makers, 50-50 partners Bell Helicopter Textron Inc. and Boeing Co., have high hopes of making an initial foreign sale of V-22s soon. Foreign orders would lower the Osprey's current unit cost from about $67 million for an MV-22B and $78 million for a CV-22B.

Critics who distrust tiltrotor technology or would prefer to see the money the Marines and Air Force spend on Ospreys go to other uses have long contended the V-22 is unsafe. Based on major mishaps per flight hour, however, the MV-22B has been one of the safest rotorcraft the Marine Corps flies over the past 12 years, with the crash in Morocco the service's only loss of an Osprey since Dec. 10, 2000.

Even counting two crashes of Air Force CV-22Bs in the past two years, the Osprey's safety record has been exceptionally good since the aircraft was redesigned and retested a decade ago. Since Oct. 1, 2001, three Ospreys have crashed with a loss of six lives. During the same period, the U.S. military has lost 414 helicopters at a cost of 606 deaths.
I honestly cant wait to see how this gets spun by Axe, Cox, and Meyer. Here's my prediction (Axe especially): "USMC quick to blame pilots for latest MV-22 incident", and then cue the rehashing of the pilot error determination for Marana and Afghanistan.
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Old 10th Jul 2012, 21:45
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I was looking in the cockpit of one at RIAT this weekend and it doesn't seem to have a collective, it does have a big lever for the nacelle but it looks a bit unwieldy, how do you control it in a hover?

Its a big Fu@@er though but looks like a nice bit of kit.
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Old 10th Jul 2012, 22:04
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Rotorboater

The cyclic/stick controls pitch and roll just like an airplane or helicopter.

The thrust lever (collective) controls the thrust.

The nacelle angle is controlled by a thumb control.

Simple.

TC
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Old 11th Jul 2012, 00:13
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The Warning cautions pilots that "severe pitch down and altitude loss can occur if nacelles are rotated too far forward too quickly at takeoff."
Jeez Louise....you reckon?

Now let's add a 20-27 knot tail wind....throw in a pedal turn at the same time....out of wind to down wind....and bad things happen.

Must be all that rapid acceleration can be addictive.

It does seem counter-intuitive to have to apply aft cyclic as you accelerate by rotating the nacelles forward. It makes sense when you consider the objective is to maintain a reasonably level airframe pitch attitude during such transitions.
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Old 11th Jul 2012, 18:42
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V-22 Osprey a shape-shifter that has come of age - The National

V-22 Osprey a shape-shifter that has come of age
David Black

Jul 11, 2012

Derided as an unsafe ugly duckling during its development, the vertical takeoff V-22 Osprey aircraft has indeed blossomed into a swan. Now widely deployed by the US air force, this high-speed plane is attracting widespread attention, including from the UAE. David Black reports

Helicopters transformed the battlefield, moving troops and equipment directly to where they were needed at 150kph and depositing them vertically on a landing zone. The V-22 Osprey can do all of that - but travelling to its drop-off and pick-up points at a maximum speed of 463kph.

"It can do everything a helicopter can do," says Major Fernando Zapata, an operations officer in the 8th special operations squadron of the US air force. "Except you get there quicker."

Maj Zapata is out on the flight line at Hurlburt Field air force base in the Florida panhandle, home to the USAF's special operations command, which "has a requirement" for 53 of the CV-22 Ospreys.

The tanned, shaven-headed Maj Zapata is a helicopter pilot by trade, but from the evangelical language he uses to describe this unlikely looking aircraft, he is a convert. Obviously there is more to the Osprey than just being faster than a helicopter.

"It's the greatest fun to fly," he says. "Pretty much a dream. You get behind that stick and you know you're not flying a helicopter. You're not flying a fixed-wing [aircraft] either. It's a tilt-rotor, and I guess we're still finding out just exactly what that's going to mean."

The UAE Air Force is also keen to find out what it's going to mean. Since the Osprey's crowd-pleasing appearance at last year's Dubai Airshow, Boeing-Bell has been in discussions to sell the aircraft to the Emirates, India, Japan and Canada.

This week the Osprey is strutting its stuff at the Farnborough International Airshow in England. But it has taken a long time to get here.

The aircraft began life as a result of a US department of defence requirement issued in 1981 for a joint-service vertical take-off and landing experimental aircraft. It first took to the air in 1989, but it was to take two decades, four fatal accidents, a reputation for unreliability and several attempts by politicians to kill it off, before Boeing-Bell managed to turn this ugly duckling into a swan.

Now, despite having US$500 billion (Dh1.83 trillion) chopped out of its budget, the Pentagon is buying 360 MV-22s for the US Marine Corps in addition to its USAF special forces quota, and potentially, a further 50 for the US navy.

Yet seldom has an aircraft encountered so much public hostility. There were problems - leaking hydraulics, engine mounts that had a habit of catching fire and its rotor performance in certain flight configurations made the aircraft unstable. Three training crashes killed a total of 30 Marines.

In 2007, a Time magazine cover story labelled the Osprey "A Flying Shame" and in the past year The New York Times has described the V-22 as "accident-prone" and "unsafe".

But as Richard Whittle points out in The Dream Machine: The Untold History of the Notorious V-22 Osprey, his book on the development of this revolutionary aircraft, the engineers were working at the cutting edge.

The V-22 is a complicated aircraft, engineering-wise. It takes myriad hydraulic and fuel lines to tilt and drive almost 500 kilograms of 6,100-horsepower engine on each wing tip. And it is a shape-shifter, so the wing must take all the stresses as the rotors tilt at full-power and transform the aircraft from turbo-prop transport plane into helicopter.

The fuselage must also be tough enough to resist all the resulting structural stresses. Adding to the challenge, the engineers had to design rotors that folded to save space so the V-22 could operate from ships.

This was a new type of aircraft, with new kinds of challenges. Yes, there were engineering problems - but problems are what engineers fix.

A redesign on the hydraulic feeds to the engine tilt-mountings cured the fire problem. The aerodynamic problem was an old one.

Vortex ring state (VRS) occurs when a rotorcraft descends too quickly and dips its rotors into its own downwash. The result is that rotor blades lose all lift. On the Osprey if one rotor dips into downwash and the other does not, the aircraft flips over.

VRS killed 19 Marines in one accident during the aircraft's development.

Now, Ospreys have audio and visual warnings alerting pilots to VRS, and they are trained to tilt the rotors forward to build speed and escape the effect.

The aircraft has now been in service for five years, flying in some of the most inhospitable conditions imaginable, mostly with the US Marine Corps. So far, there has been only one fatal combat crash: in 2010 in Afghanistan, aUSAF CV-22 missed its landing zone, killing four of the 20 aboard.

"Over 10 years, Ospreys have been the … safest combat rotorcraft," said Mr Whittle, the author of The Dream Machine.

The rest of the world is starting to listen to the Osprey's "war stories". In 2010, a special forces operation in Kunduz in north-eastern Afghanistan ran into trouble, leaving troops pinned down by enemy fire.

Dust storms prevented helicopters from launching a rescue, but two USAF CV-22s from Kandahar, 643km away on the other side of the 4,572-metre-high Hindu Kush, made it to the landing zone and had 32 US personnel back at base in less than four hours.

And last year, an F-15 pilot who ejected from his aircraft over Libya was rescued by MV-22s flying from an amphibious assault ship 241km away in the Gulf of Sirte. The Marines had the pilot back aboard in just 30 minutes. Sitting in the simulator at Hurlburt Field, Maj Zapata powers up for a flight.

"This controls the tilt rotor angle," he says, indicating a tiny roller on the control stick. "Completely different from a helicopter where you are hauling on the collective to adjust your angle of attack."

A short roll forward, and up we go at an improbable angle and incredible speed.

He spins the roller, the rotors tilt to horizontal and we transition from fast to faster. Pilots who qualify on the Osprey will have flown fixed-wing aircraft and helicopters. Here they learn all the trades they will be expected to master as tilt-rotor jockeys.

V-22s, with their crew of two pilots and one other airman, can fly as many as 24 troops into battle at 262 knots, and evacuate casualties on 12 stretchers. The craft has a cargo hook to lower and retrieve from the hover, and it is much more "tactically agile" than a helicopter, according to the manual.

"That means you can get in and out of Dodge fast," according to crewmen on the flight line.

It can land on runways, or hillsides, in all weathers, including the dust "brown-outs" that frequently defeat helicopters. It can also land on ships of all classes from aircraft carriers to frigates.

It is, however, expensive. The V-22's research and development programme was supposed to cost $39bn, but independent estimates put that at $56bn now, meaning a price tag of about $100 million per aircraft.

It is hoped to get that down to $67m, but Boeing says buyers have to balance the price of the aircraft against its operational flexibility. Say you wanted to fly supplies to a disaster zone: there's the cost of flying a C-130 Hercules to a forward airfield, the cost of transferring the supplies to helicopters and flying them to the scene.

Or you can use an Osprey. One mid-air top-up with fuel, and refuelling at the other end, and the V-22 has a 2,200km range to a disaster area. And did I say it's fast?
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Old 11th Jul 2012, 21:42
  #240 (permalink)  
 
Join Date: May 2002
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"It can do everything a helicopter can do,"

Well....almost!
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