This is interesting. The crash of an F-22 Raptor out of Elmendorf Air Force Base in Alaska late last year was not caused by problems associated with the plane's oxygen system, Air Force Chief of Staff, Gen. Norton Schwartz told Air Force Magazine yesterday.
The onset of summer in Alaska allowed investigators to get their hands on "hardware and computer memory that made a more comprehensive analysis possible," wrote John Tirpak of Air Force Magazine. This analysis apparently led the investigators to decide that problems with the oxygen system didn't cause the crash. The investigation had been delayed by harsh winter weather that kept investigators from recovering all the evidence from the crash site.
The service began investigating the Raptors' on-board-oxygen-generating-system after the fatal crash in late November 2010. The investigation has been looking at whether carbon monoxide and other toxins are seeping into the system, called OBOGS, that provides pilots with air to breath at high-altitudes. 14 Raptor pilots at six bases around the United States have reportedly experienced hypoxia-like symptoms after using the OBOGS system.
Suspected problems with the oxygen system famously led to the grounding of the entire F-22 fleet in early May -- a grounding that remains in effect. (Schwartz also told AF Mag that the F-22s will be flying soon and that the Raptors' flight to flee Hurricane Irene last weekend was the start of a phased plan to get them back in the air.)
Via: Air Force Magazine.