* New restrictions seen as sufficient to guarantee safety
* Pentagon hasn't ruled out grounding F-22 again if
By Phil Stewart and David Alexander
WASHINGTON, May 15 The Pentagon announced on
Tuesday new safety precautions for its F-22 fighter jets -
including limiting how far they can fly from airstrips - after
pilots experienced symptoms of oxygen deprivation aboard the
advanced stealth aircraft.
U.S. Defense Secretary Leon Panetta believes the new
precautions on the F-22s, built by Lockheed Martin Corp,
are sufficient to guarantee safety. But the Pentagon did not
rule out grounding the aircraft again, if necessary.
Panetta "will be receiving regular updates, and all options
remain on the table going forward," said Pentagon spokesman
The F-22s were grounded for over five months last year
because of the same issue. But concern over the jet's safety has
again taken the spotlight after CBS's "60 Minutes" program aired
a report this month in which two pilots said they had stopped
flying the fighter due to safety concerns.
The report raised concerns on Capitol Hill, where lawmakers
questioned why the Air Force has not yet been able to get to the
cause of the problem. A top Air Force official faced tough
questioning over the issue at a hearing last week in the Senate.
In the short term, the Pentagon said the decision to limit
the distance that jets can fly from landing strips means that
other aircraft instead of the F-22 will need to perform
long-duration airspace-control flights in Alaska.
The Air Force will also expedite installation in the jets of
an automatic backup oxygen system, with the first systems being
fitted before the end of the year.
Pentagon spokesman John Kirby said the first reported
hypoxia-related event occurred in April 2008, with a total of 12
reported between then and January 2011.
Last week, Lieutenant General Janet Wolfenbarger told a
Senate Armed Services subcommittee that the Air Force had
implemented over a dozen new procedures to ensure pilot safety
in the F-22 and noted that potential problems with oxygen only
occurred on 0.1 percent of all flights.
Little said a wide range of potential causes for the problem
were still being considered.
"We haven't determined the root cause," he said. "It could
be something connected to the oxygen system. It could be other
aspects of the aircraft that could contribute to hypoxia-like
events, whether it's G forces, the altitude at which the plane
Concerns over the F-22 have also raised questions about
whether the new F-35 fighter jets being developed by Lockheed
could face similar issues. The stealthy, high-tech F-35 will
have many of the capabilities of the F-22 but will not be able
to fly as high or as fast.
"I think it's safe to say that everybody in leadership is
concerned about this," Kirby said, adding that everyone was
"going to work very hard to make sure that the problem gets
solved for this aircraft and doesn't get repeated in another."