The Air Force has found that an air supply problem had been causing the hypoxia-like symptoms for some pilots flying F-22 Raptors, the Pentagon announced this week, adding that the service has made two changes in the aircraft’s cockpit life-support system to correct the symptoms, which include nausea, headaches, fatigues and blackouts.
The Air Force will replace a valve in the upper pressure garment vest worn by pilots during high-altitude missions, Pentagon spokesman George Little said. The valve was causing the vest to inflate improperly, causing breathing problems for some pilots.
The second change involved increasing the volume of air flowing to pilots by removing a filter that was installed to detect contaminants in the oxygen system. Oxygen contaminants were ruled out as a cause for the hypoxia-like symptoms. The Air Force is also exploring to improve the oxygen-delivery hose.
With the two changes to the fighter jet, Defense Secretary Leon E. Panetta authorized the deployment of a squadron of F-22s to Kadena Air Force Base in Japan, which will happen in the next coming days, according to Gen. Norton Schwartz, the outgoing chief of staff of the Air Force.
After repeated incidents of the hypoxia-like symptoms reported by pilots since 2008, the Defense Department in May imposed flight restrictions on the F-22 and grounded all F-22 air space patrol fights in Alaska. Mr. Panetta this week approved the Air Force’s plan to remove flight restrictions over time, Mr. Little said.
“This process starts today,” Mr. Little said. “The gradual lifting of restrictions will enable the Air Force to resume normal F-22 operations over time, while ensuring the safety of the incredible airmen who fly this critical aircraft.”
Sen. Mark Warner, Virginia Democrat, and Rep. Adam Kinzinger, Illinois Republican, welcomed the Pentagon’s decision to lift the restrictions gradually.
“We certainly look forward to much more specific information about these problems and proposed solutions during our briefing with the Air Force, which has been scheduled for July 31st,” they said in a joint statement Tuesday.
They also urged the Air Force to rescind disciplinary measures pending against two Virginia Air National Guard members, who appeared earlier this year on CBS’s “60 Minutes”, discussing why they refused to fly the F-22s due to their concerns over the oxygen problem.