The Air Force Scientific Advisory Board has been asked by the Secretary of the Air Force to do a quick-look study of the onboard oxygen generation system used by the F-22, the nation’s newest air superiority fighter.
The F-22 fleet has been in stand-down mode since May due to a suspected flaw in the OBOGS, although there are indications that another cause may be at work. At least 14 incidents of pilot “hypoxia-like” symptoms have been reported.
The board will also review OBOGS on the A-10, F-15E, F-16, F-35, B-1, B-2, CV-22, T-6 and other aircraft. Robins Air Force Base officials who manage the Air Force’s F-15 fleet earlier reported no problems with the Eagle. The F-15E employs a different type of OBOGS from the F-22, local expert have confirmed.
Air Force public affairs officials said a series of carefully controlled in-flight tests will examine the OBOGS components including the pressurization system, mask and cockpit oxygen levels.
“The safety of our aircrews is paramount,” Air Force Chief of Safety Maj. Gen. Gregory Feest said in a Thursday Pentagon news release. “The review is a prudent step to ensure that.”
Other than the F-22, there is no plan to stand down any other system. “Air Force units will continue normal operations during the quick-look study,” officials said.
Meanwhile, investigators at Elmendorf Air Force Base, Alaska, believe they may have found the problem. Air Force Times is reporting that a harsh weather practice of starting aircraft engines inside a hangar could be the culprit. Most of the OBOGS incidents have occurred at Elmendorf.
According to the Times, investigators suspect that engine “exhaust gases are getting trapped in the building, sucked back into the engines then enter the bleed air intakes that supply the OBOGS.”
The Air Force had no immediate comment on the air intake possibility, Air Force Times indicated.