Posted on 10/27/2005 6:10:59 AM PDT by pabianice
Washington October 25, 2005 - An Air Force version of the V-22 tilt-rotor Osprey aircraft last week experienced a compressor stall of both engines after flying into a cloud at 18,000 feet, presumably because of icing problems, sources have told the Project On Government Oversight. The aircraft, CV-22 #6, was on a routine flight to Edwards Air Force base in California. It did not recover from the stall until it had descended to warmer air at about 10,000 feet, the sources said.
As a precaution the aircraft landed in Prescott, Arizona.
"This is very disturbing. Only last month the Pentagon approved the Marines version of V-22 for full-rate production," said POGO Senior Defense Investigator Eric Miller. "And now we find out the aircraft can't even fly into a cloud."
At the time of this release, it was not known whether the aircraft that experienced the stall had a de-icing system onboard. It's also unclear just how much, or if any, de-icing system testing has been performed on the CV-22. A report of testing issued last month by the Director of Operational Test and Evaluation on the Marines V-22 did not address the issue of icing. A 2000 DOT&E report said that icing testing on the Marines V-22 had been waived by the Navy. Sources have speculated to POGO that the V-22 cannot take on extra weight without impacting its performance, and a de-icing system would add weight.
The requirement that the aircraft be able to operate in icing conditions was waived during the first phase of operational testing in 2000. The report also predicted that there was no plan to evaluate operations in icing conditions during OPEVAL Phase II. "The operators will be restricted from flying in icing conditions until the development testing and follow-on operational testing is completed," the 2002 report to Congress said.
There is another concern raised by the dual-engine failure. Because the Pentagon and defense contractors have been saying that the loss of both engines in the V-22 is "remote, but possible," they have deleted the original requirement that the V-22 be able to autorotate like nearly all other helicopters to a soft landing in the event of engine failure. In the event of a single engine failure, V-22 flight procedures require the pilot to transition to aircraft mode and in the event of a second engine failure perform a "fixed wing glide approach to an emergency landing site," according to an April 2002 report to Congress.
In fact, had the emergency dual engine stall over Arizona been below 1,600 feet, it would "not likely" be survivable, according to the recent DOT&E report.
The Air Force plans to buy 50 CV-22's to replace its fleet of MH-53J Pave Low helicopters used to insert and extract special operations force from enemy areas. Although the CV-22 is on a different development and testing track than the Marines MV-22, it team of developers and testers work together on many common areas.
The Air Force version of the V-22, the CV-22, is a modified version of the Marines MV-22 to perform longer-range, special operations missions. The CV-22 is modified to have long-range fuel tanks, advanced radar, and more sophisticated situational awareness and radio frequency countermeasures. These modifications are designed to improve operations during night and low altitude flights in bad weather. The report to Congress also said there was no plan to evaluate operations in icing conditions during OPEVAL Phase II. "The operators will be restricted from flying in icing conditions until the development testing and follow-on operational testing is completed," the report said.
Founded in 1981, the Project on Government Oversight is an independent nonprofit, which investigates and exposes corruption in order to achieve a more accountable federal government.
To say the least.
. . . and a huge waste of money.
The Osprey is nothing but a debacle.
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It has sure been plagued by bad luck -- the real question is, why can't they get it right? There is nothing about that aircraft that is mystical technology. Engines freezing up ? --- hmmm.
Maybe, but it's STILL killed less Marines than the CH-46 has. The CH-46 is a *huge* debacle all of its own.
Full production start-up was given the go-ahead without testing something very basic and crucial with any aircraft - icing issues.?
Good point...
To this day, I dont understand why the government went with a "Tilt Rotor" design and not some sort of vectored Jet Thrust system.
Oh, c'mon. There's an easy workaround: Just don't fly through clouds. Duh. /sarc
Um...I'm no pilot, but if you're going to be building something that's designed to fly in ALL weather conditions, don't you pretty much HAVE to have de-icing equipment on the wings, tail, props, engines, and pitot/static system?
Good grief, did they forget to put in the artificial horizon and a VOR radio while they were at it?
}:-)4
How many deaths before a bad design is canceled?
Ten bucks says the maintenance logs on that particular V-22 are incomplete...
Vectored thrust, like the Harrier?
The Harriers nickname is "The Widow Maker", not for its fighting ability, but for its flying ability. 1/3 of all Harriers have crashed.
USMC aviation has a proud tradition, but IMHO, they need to stay out of aircraft development.
Though not an engineer, I would assume it hs to do with close quarter maneuverablility. Marines use it to place troops on the ground. AF uses it for flying. I guess they have a need for short runway usage. Thrust would be better for AF, but rotors probably better for Marines..
I have a place near Cape Carteret, NC, along with Cherry Point, and Camp LeJeune. I have observed plenty of Ospreys, and Harriers.
I fly fixed wing. I'd love to take a ride in either... just for S&G...
I ain't taking that bet!
This thing not only looks like it doesn't want to fly, it really can't fly.
(1)The turbine engines encountered internal compressor icing in IMC conditions...??... OR
(2) The props/rotors encountered blade ice, thus dragging down rotor RPM...??...OR...??
It was not known whether the aircraft that experienced the stall had a de-icing system onboard.
(3)Some desert-based zoomie forgot to turn the engine anti-ice... with quite predictable results...??... OR, finally...
There is another concern raised by the dual-engine failure.
(4) Since a compressor stall... even a dual compressor stall... isn't really an engine failure but a tEmporary interruption of proper airflow... Is this entire encounter a bit of "bloody-shirt" for the opponents of the Osprey program...
I'm just askin'.... That's all....
Nice day to all,
That turkey will not fly.
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