Update Osprey Crash: "Design Flaw" Blamed

greenspun.com : LUSENET : Grassroots Information Coordination Center (GICC) : One Thread

WASHINGTON (Reuters) - Marine Corps pilots who were part of an investigation of the December crash of an MV-22 Osprey aircraft blamed the crash on a design flaw that had been known for months but not fixed, The Washington Post reported on Thursday.

The Marine Corps' report on the December 11 crash near Jacksonville, North Carolina, which killed all four crewmen, was expected to be released as early as Thursday, the Post said.

The pilots told the Post they believed the problems with the MV-22 slipped by because the Pentagon wanted to secure full funding of the troubled aircraft program.

Not long after the North Carolina crash, Marine investigators suspected hydraulics failure combined with a software glitch was the cause. But pilots on the mishap board told the Post they believe senior Marine officials knew about the problem long before the crash and put off taking care of it.


-- Rachel Gibson (rgibson@hotmail.com), April 05, 2001


Osprey Crash Blamed on Leak, Software

By Mary Pat Flaherty Washington Post Staff Writer Friday, April 6, 2001; Page A02

The Marine Corps reported yesterday that a hydraulic leak and a software glitch caused the fatal crash of a V-22 Osprey in December, and it called for a redesign of the faulty systems, which could set back development of the aircraft by more than a year and increase pressure on the Corps to buy alternative helicopters.

The accident report, released at a Pentagon briefing, confirmed that both the Marines and private defense contractors were aware of serious problems with the hydraulic system more than a year before the crash, which took the lives of four Marines.

Neither the report nor Marine officials explained why the chronic problems went uncorrected. The Washington Post reported yesterday that several Osprey pilots who were involved in investigating the accident believe that the flaws were not addressed because the Corps was intent on winning Pentagon approval for the aircraft to go into full production. That decision was postponed after the December crash.

The accident report noted that "testing of the V-22 aircraft was timeline based" -- driven to meet a schedule -- "instead of based on actual performance."

Maj. General Martin Berndt, who delivered the report, declined to answer questions about whether the Corps or the Osprey's manufacturers -- Bell Helicopter Textron Inc. and Boeing Co. -- were negligent or failed to pay sufficient attention to safety. Both companies said yesterday that they could not comment on the report until they've had a chance to review it and discuss it with "our Marine Corps customer."

Release of the report came just as a Defense Department review panel is preparing recommendations on the future of the Osprey, a hybrid aircraft that takes off and lands like a helicopter but can tilt its rotors forward to fly like an airplane.

The Marine Corps has proposed to buy 360 V-22s, for a total of about $40 billion, to replace its aging fleet of Vietnam-era helicopters. But two accidents last year that killed 23 Marines and an ongoing investigation into allegations that maintenance records were falsified at the Osprey squadron in New River, N.C., have left the program on hold. Berndt said there is no evidence that records for the Osprey that crashed in December had been doctored.

The squadron has been grounded since the crash, which the report recounted in detail. Preparing to land at night near Jacksonville, N.C., Lt. Col. Michael L. Murphy, 38, tried to shift the rotors from the horizontal, airplane mode into the vertical, helicopter mode. But midway through the shift, a hydraulic line burst.

In the cockpit, a light flashed. Murphy and Lt. Col. Keith M. Sweaney, 42 -- the two most experienced Osprey pilots in the Marine Corps -- responded by the book. They hit the reset button on the computerized flight control system, then hit it again as the aircraft bucked and rolled left. The pilots punched "reset" again and again -- between eight and 10 times during the final 20 seconds -- to no avail.

"Declare emergency. We're going down, we're going down," they radioed before the Osprey stalled and plummeted nose down into a marsh, bursting into flames.

The software problem "absolutely" hastened the descent, and the hydraulic leak alone would not have caused the crash, said Berndt, commanding general at Camp Lejeune, home to the Osprey squadron.

Berndt said the report asked the Navy and the manufacturers to "investigate a possible redesign" of the hydraulic system and sought a "comprehensive review" of the software. The report itself, however, flatly called for a redesign of both systems.

Gidge Dady, a spokeswoman for the Naval Air Systems Command Center at Patuxent, Md., which would oversee any redesign, said she could not predict how long it would take or how much it would cost.

Jacques S. Gansler, former undersecretary of defense for acquisition, technology and logistics, estimated that the redesign could be done in as little as three or four months. But Philip E. Coyle, who retired this year as the Pentagon's chief weapon tester, said the reengineering and follow-up testing could take a year or two if the Marines and the manufacturers want to be sure that all key systems are working properly.

The Osprey was designed with a triply redundant hydraulic system and a triply redundant flight control software system. However, at the point where the leak occurred in December, two of the three hydraulic lines shared a common tube that was worn through. The software glitch involved a problem that had not been uncovered during earlier testing.

Osprey pilots and mechanics have criticized the design of the engine housing as too tightly packed with crucial lines, such as hydraulic ones, that are vulnerable to abrasion.

Knowledge of the hydraulic problem went back at least to July 1999, the report said, noting that after the crash an inspection found chafed hydraulic lines in all of the Marines' eight remaining Ospreys.

On Capitol Hill, longtime Osprey supporter Rep. Curt Weldon (R-Pa.) said the report raised important issues but "should not be a showstopper" for a technology that he contends is basically sound.

However, Sen. Russell Feingold (D-Wis.) said the report "only enforces my view that further procurement of this aircraft should be delayed."


-- Carl Jenkins (somewherepress@aol.com), April 06, 2001.

Moderation questions? read the FAQ