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Can anyone explain this to me? It seems quite strange.:

V-22 Engines Freeze: Can't Fly Through Clouds
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

Well I guess if the temp / dew point spread was obviously low, and the temp was low enough, any jet can build up ice on the leading edge of the intake. Its just the venturi effect and really shouldnt be a surprise unless there was de- and or anti-icing equipment that didnt work. And if it was older style de-icing boots they could have been used wrong. It may have been just the correct conditions in the cloud also. There can be some pretty freaky weather inside of clouds, especially ones with strong returns or no returns that may signify heavier inmbedded weather within the cloud. Who knows ?

"By this time tomorrow I shall have gained either a peerage or Westminster Abbey !" Nelson the Immortal Memory

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<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>V-22 Engines Freeze: Can't Fly Through Clouds<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

There is more conflicting information out there on the V-22 than anything I've ever seen. What about this?

V-22 Icing Detachment Returns from Halifax
Story Number: NNS040507-07
Release Date: 5/7/2004 1:34:00 PM


By Ward Carroll, Naval Air Systems Command Public Affairs

PATUXENT RIVER, Md. (NNS) -- Osprey No. 24 returned to Naval Air Station Patuxent River on the afternoon of April 29, after spending six months conducting aircraft icing tests from Canadian Forces Base Shearwater near Halifax, Nova Scotia. During the detachment, Osprey No. 24 logged 67 hours, 37 of which were in actual icing conditions...

<i>and this</i>
Aerospace Daily
December 1, 2004
Marc Selinger

The V-22 Osprey program is studying ways to fine-tune how it operates its airborne de-icing equipment after a rotor blade on a test aircraft was damaged, apparently by a piece of ice that formed on the tiltrotor transport and broke off during flight, a program spokesman said Nov. 30.

<i>and this</i>
http://www.globalsecurity.org/military/ ... urvive.htm
...The Osprey is designed to operate in weather that would ground current generation helicopters. Ice Detection, Anti-Icing on the engine inlets, windshield, pitot-static/angle-of-attack probes and parts of the proprotors and De-icing of the proprotor blades, spinners, wing and tails are part of the Osprey's design...


<i>And it is unclear from the article whether the compressor stalls flamed out the engines, or they continued running in an unstable state until descent to a lower altitude. It sounds incredible that a double engine flameout at 18000 ft can be survivable. With windmilling rotors the V-22 probably has a lift/drag ratio like the space shuttle, rather like a brick, and handling qualities like a car on ice. I think I would soil myself.</i>


It ain't the heat it's the humility.

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They probably did soil themselves.... <img src=newicons/anim_shock.gif border=0 align=middle>

Hokey religions and ancient weapons are no match for a GAU-8A at your side, kid...--Hawg Solo

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\"Hokey religions and ancient weapons are no match for a GAU-8/A at your side, kid.\"--Hawg Solo

It's hard to believe a plane that looks like that has problems..

I wonder if it was icing on the plane or icing on the propellers that was causing the problem. Obviously icing on the props could be a huge problem when so much in that aircraft depends on no vibration from the props.

Just send the Osprey over to NASA and order some CH-71s. Tit-rotor is a novel idea, but It really doesn't work in a combat situation.

My motto: pacis per vires

How many Ospreya are in the fleet ? Yeah they still have problems but it seems to me they get used a lot and do allright.

"By this time tomorrow I shall have gained either a peerage or Westminster Abbey !" Nelson the Immortal Memory

_________________
YGBSM !

<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
Yeah they still have problems, but it seems to me they get used a lot and do allright.
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Roger that.

It ain't the heat it's the humility.

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There are no ospreys in the fleet that i'm aware of.

They've not been fielded yet.

And i don't care if they work even better than advertised(and they don't), becuase they're woefully overpriced regardless.

<b>There are two kinds of soldiers.
Snipers...and targets.</b>
<img src="http://www.creedmoorsports.com/images/SA9121-M21.JPG" border=0>

This is an Osprey pollyanna newsletter piece. The best article is the "MV-22 Demo Ride...".

http://www.boeing.com/rotorcraft/milita ... sept05.pdf



It ain't the heat it's the humility.

_________________
????