Marines: Software is one culprit in Osprey crash
The Marine Corps is nearly certain the Dec. 11 crash of an MV-22 Osprey that killed four Marines was caused by hydraulic failure followed by malfunctioning software.
align="right" width="297">Lt. Gen. Fred McCorkle, deputy commandant of the Marine Corps for aviation, said the accident appears to have been 'a hydraulic system failure followed by an error in software inputs to the flight control system.'McCorkle said there was a single hydraulic line that ruptured after chafing from some object. 'When that occurs, you get a hydraulics failure warning in the cockpit and then you go into emergency procedures after that,' McCorkle said. It was at this point that the backup program hiccuped.Since 1991, the Osprey has been involved in four accidents'three of them fatal'leaving some critics questioning the high-tech aircraft's safety record, as well as the $30 billion price tag if brought into full production. The MV-22, with its tilt-rotor technology, takes off and lands like a helicopter, although it can fly at twice a helicopter's speed.The Marine Corps stands behind the Osprey, although Nevers acknowledged there are some legitimate complaints concerning the aircraft's reliability and maintainability.The Corps maintenance data has proven to be less reliable than what is required, according to a report prepared by Defense's Office of Operational Test and Evaluation.Although those figures 'have not been where we want it to be, it's getting better,' Nevers said.The latest crash, as well as the fatal crash last April, is under investigation by the DOD inspector general. The IG review will likely take two to three months.The IG, in part, is investigating whether falsified maintenance records at the Osprey squadron's headquarters at the Marine Corps Air Station New River contributed to the Dec. 11 crash. This inquiry resulted in a squadron commander being relieved of command.The action taken against Lt. Col. Odin F. Leberman was prompted by an anonymous letter accusing him of ordering officers to cover up maintenance problems. Leberman has not been charged with anything, although the investigations continue. Col. Richard Dunnivan has replaced Leberman.In January, McCorkle said he was confident the crash had nothing to do with the maintenance cover-up allegations. He also dismissed questions suggesting the accident was caused by pilot error or design flaws.The Corps is wrapping up its official report, being done by an officer outside the program along with representatives from the Air Force, Navy and National Transportation Safety Board. This report will be finished by month's end, Nevers said.'We have never seen a link between maintenance and the accident ... from the start,' McCorkle said. 'It had zero to do with technology with the tilt-rotor or with the MV-22. I will tell you that there was no pilot error associated with this second aircraft accident.'Since the accident, the Corps has suspended MV-22 flight operations, pending the outcome of the investigations, which in addition to the Corps and IG reviews include a Blue Ribbon Panel study commissioned in December by former Defense secretary William Cohen. Cohen asked the panel to make recommendations on whether to continue with the Osprey program. It will submit its findings in early summer.
size="1" color="#FF0000">Lt. Gen. Fred McCorkle, left, answers questions during a briefing about the December Osprey crash near Jacksonville, N.C. Petty Officer 3rd Class Jerry Lowe directs one of the experimental aircraft as it lands aboard the assault ship USS Essex, top, off the coast of Southern California.
Backup failure
First findings
The Marine Corps is nearly certain the Dec. 11 crash of an MV-22 Osprey that killed four Marines was caused by hydraulic failure followed by malfunctioning software.
'That accident was not related to anything inherent in the design of the aircraft,' said 1st Lt. David Nevers, a Marine Corps spokesman. 'We're 99 percent sure it was [caused by] hydraulic failure, which prevented the backup system from working.'
The Corps would not divulge details about the software used to support the controversial aircraft's hydraulic system, citing a pending investigation by an independent Defense Department commission. The Osprey crashed near Jacksonville, N.C., just eight months after an Osprey went down in Arizona, killing all 19 Marines on board.
Backup failure
First findings
NEXT STORY: Senate adds servers to speed up e-mail