May 15 (Bloomberg) -- The Pentagon said it is imposing new safety measures on Lockheed Martin Corp.’s F-22 fighter planes, including limiting flight durations and speeding the installation of back-up oxygen systems.
The Pentagon announced the steps today as the Air Force continues to investigate why F-22 pilots are experiencing symptoms of oxygen deprivation, or hypoxia.
“The idea is to ensure there’s a prudent amount of safety built into each of these flights,” Navy Captain John Kirby, a Pentagon spokesman, said at a news conference. While the Defense Department depends on the plane, “this is an engineering problem that needs to be solved,” Kirby said.
Two pilots went public with their concerns about the plane’s safety, citing oxygen deprivation and disorientation, in a report last week on CBS’s “60 Minutes” program.
At least 12 reported cases of hypoxia symptoms have been reported since April 2008, Kirby said.
Defense Secretary Leon Panetta “is deeply concerned about pilot safety,” spokesman George Little said. “That’s a paramount concern for him.”
The first retrofit of the plane’s oxygen system will be completed in December, Kirby said. Planes will be retrofitted beginning next year at the rate of ten a month.
‘Deeper We Dig’
“The deeper we dig, the more uncertain I am we’ve found the root cause yet,” said Senator Mark Warner, a Virginia Democrat who was briefed by the Air Force today and spoke to reporters in a conference call. Langley Air Force Base in Virginia is home to some of the F-22 pilots.
Warner said nine pilots and flight surgeons have expressed their concerns about the plane’s safety.
“It’s an extraordinary step to come forward, even under anonymity,” said Representative Adam Kinzinger, an Illinois Republican and former Air Force pilot who joined Warner on the call. “In the pilot culture, that’s not something that’s taken lightly.”
The stealthy F-22 Raptor, which has never flown in combat, was grounded for four months last year as the Air Force struggled to diagnose the troubles with oxygen that have caused symptoms such as dizziness and blackouts.
The Pentagon order curtailing long-distance flights means patrols of U.S. airspace over Alaska will now be performed by other aircraft, Kirby said.
Warner, who called for an expanded Air Force investigation last week, said the Pentagon’s new safety measures were “an appropriate first step, but I want to see some more of the data.”
An Air Force notification to Congress last year said that under certain conditions, Honeywell International Inc.’s On-Board Oxygen Generating System “does not deliver oxygen as designed to the pilot, which could result in hypoxia and decreased flight safety.”
The continuing investigation “failed to reveal a single, definitive root cause for the hypoxia-like symptoms,” according to the notification.
Honeywell, based in Morris Township, New Jersey, has said on its website that its oxygen system “is more reliable, safer and requires much less maintenance than a comparable stored-gas system.”
Citing “grave concerns” about the F-22’s safety, Kinzinger said, “We have a lot of questions that still need answers.”
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