The military believes it has found the source of the potentially deadly
oxygen problem that has plagued America's most expensive fighter jet,
the F-22 Raptor, for years, Pentagon spokesperson George Little said
today.
"I think we have very high confidence that we've identified the issues,"
Little told reporters, before announcing a long-term plan to lift
strict flight restrictions imposed by Defense Secretary Leon Panetta
on the $79 billion fleet in May. "This is a very prudent way to ensure
that we, in a very careful manner, resume normal flight operations."
The mystery problem with the F-22 Raptor was the subject of an ABC News "Nightline" investigation,
which found that since 2008, F-22 pilots have experienced unexplained
symptoms of oxygen deprivation -- including confusion, sluggishness and
disorientation -- while at the controls of the $420 million-a-pop jets
on more than two dozen occasions. In one instance, a pilot became so
disoriented that his plane skimmed treetops before he was able to pull
up and save himself. The Air Force subjected the F-22 to intense
scrutiny for years, including a nearly five-month fleet-wide grounding
last year, but was unable to solve the problem. When the grounding was
lifted, the service awarded the plane's manufacturer, defense
contracting giant Lockheed Martin, a nearly $25 million contract in part to help identify the problem, but still no answer was found.
The source of the issue, the Pentagon now says, is believed to be a
faulty valve in the high-pressure vest that is worn by the pilots at
extreme altitudes -- one that Air Force officials believe is
constricting the pilots' ability to breathe.
"To correct the supply issue and reduce the incidence of hypoxia-like
events, the Air Force has made two changes to the aircraft's cockpit
life support system," Little said. "First, the Air Force will replace a
valve in the upper pressure garment vest worn by pilots during
high-altitude missions. The valve was causing the vest to inflate and
remain inflated under conditions where it was not designed to do so,
thereby causing breathing problems for some pilots... Second, the Air
Force has increased the volume of air flowing to pilots
by removing a filter that was installed to determine whether there were
any contaminants present in the oxygen system. Oxygen contamination was
ruled out."
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