Source: CV-22 crash not caused by mechanical failure

Flight International ^ | 17 April 2010 | Stephen Trimble

[Yo-Yo]

The BellBoeing CV-22 crash in Afghanistan on 8 April was not caused by a mechanical failure, according to a source familiar with preliminary findings of the US military investigation.

The fatal crash, which killed four and injured others, occurred after the pilot lost situational awareness while landing in a wadi around 1am under brown-out conditions, the source says.

The incident killed the pilot, a flight engineer, an army Ranger and an unidentified civilian.

Air Force Special Operations Command (AFSOC), which owns the CV-22 fleet, was not immediately available to comment.

US military officials have previously stated the cause of the CV-22 crash in Afghanistan was still under investigation. Military spokesmen, however, have ruled out enemy fire as a potential cause.

The 8 August crash is the first fatal accident involving a V-22 Osprey tiltrotor since December 2000, and is the fifth fatal crash in the programme's chequered history.

In 2000, two fatal crashes within eight months caused by mechanical failure forced military leaders to put the programme on hold for two years while contractors re-designed systems and the airframe to improve safety.

After declaring the MV-22 fleet operational in 2007, the US Marine Corps has deployed its version of the Osprey in Iraq and Afghanistan without suffering a fatal crash.

USMC officials have praised the MV-22's performance, although the service has acknowledged concerns about unexpectedly high costs to operate and maintain the unique tiltrotor fleet.

AFSOC, meanwhile, had deployed six CV-22s delivered so far to Africa, Iraq and Afghanistan before sustaining the crash.

The brown-out scenario during landing is recognized as a major safety concern for all rotorcraft operating in areas with loose sand. A recent study by the Office of the Secretary of Defense has concluded that 80% of the US millitary's 320 rotorcraft crashes during the last decade has been caused by degraded visual awareness.

[Yo-Yo]

Prayers to the families of the four victims.

CV-22A Osprey (Boeing photo)

[GeronL]

Those blades kick up dust so much that it causes that kind of thing, right?

[Yo-Yo]

The last sentence of the article says that it is a common problem with all rotary wing aircraft, not just the V-22 Osprey.

Some argue that it is a greater problem with the Osprey because of it's higher disk loading, which results in higher velocity downwash, when compared to a pure helicopter.

[DainBramage]

Landing in a wadi would only tend to intensify the brown out conditions.

One Army Ranger and one unidentified civilian.... special ops command......hmmm.

[LTCJ]

RIP

[phormer phrog phlyer]

I thought the V-22 had some type of system to handle this situation, to hover land in reduced visibility. I flew SH-2’s and SH-3’s and there was a doppler system to hover over water and maintain a fixed position.

[A.A. Cunningham]

In 2000, two fatal crashes within eight months caused by mechanical failure

Bull s***, Trimble. The Marana crash in April of 2000 was due solely to pilot error. The New River crash in December of 2000 was due to a hydraulic line rupture with aircrew error as a contributing factor. Other V-22s had previously experienced similar hydraulic failures without loss of the aircraft.

[A.A. Cunningham]

The FCS has a hover-hold function that has to be enabled and the aircraft is also equipped with flight path vector displays for manual landings.

'The swirling sand and dust in brownouts stirred up in the desert is one of many occupational hazards a helicopter pilot faces in Iraq. Freeland was moved by how the flyby- wire flight control system of the MV-22 made that a moot point. By pushing a button, the pilot commands the aircraft holds a stable hover.

“The pilot has only to retard the thrust control lever while the aircraft maintains its longitudinal and lateral position all the way to the ground,” Freeland said. “This capability, along with using the velocity vector and instantaneous acceleration cue on the hover display page to shoot manual approaches, gives the V-22 Osprey one of the most robust brownout landing capabilities of any aircraft in the inventory.”'

[DoughtyOne]

The sad thing is, that even though the V22 is an amazing aircraft, it’s intriguing design is it’s undoing.

I don’t mean mechanically. I mean that every time there is a problem with this aircraft, people go postal over it. That’s a damned shame.

“Oh did you hear? There was another problem with the V22. I said that thing would always cause problems. I was right.” Nevermind that we’ve had problems with all other aircraft during development and deployment.

The fact is, this aircraft greatly expands the deployment range of our troops. It allows us to safely transport to the far reaches of the areas where we are at battle. It allows us to put more feet on the ground there.

It’s range is superior to other aircraft used for these purposes. It’s load capability is superior.

I don’t like seeing a single one of our troops hurt or killed. It’s my impression that being more effective saves lives. And the V22 makes us a lot more effective.

My heart goes out the family and friends of those lost. They died for me and mine. I salute them.

[phormer phrog phlyer]

Thanks for the info.