Like the title says, sounds rather serious
US grounds fleet of F-22 fighter jets, indefinitely
http://sg.finance.yahoo.com/news/US-gro ... 1.html?x=0The US Air Force has grounded its entire fleet of F-22 fighters, the most sophisticated combat aircraft in the world, after problems emerged with the plane's oxygen supply, officials said Friday.
The radar-evading F-22 Raptors have been barred from flying since May 3 and Air Force officials could not say when the planes would return to the air.
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In one case, an F-22 scraped tree tops before landing and the pilot could not remember the incident, indicating a possible symptom of hypoxia from a lack of air, the magazine reported.
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"We are still working to identify the exact nature of the problem. It is premature to definitively link the current issues to the OBOGS system," she said.
Since January, F-22 pilots have been barred from flying above 25,000 feet (7,600 meters), following the crash of a Raptor jet in Alaska during a training flight.
Grounding an entire fleet of aircraft is a rare step, officials said.
