WASHINGTON - Insufficient oxygen supply caused some F-22 fighter pilots to get dizzy and disoriented when flying the most advanced US warplane, the Pentagon said on Tuesday, signaling at the conclusion of an Air Force study that restrictions placed on F-22 flights would gradually be lifted.
Pentagon spokesman George Little said an Air Force analysis had concluded that symptoms of oxygen deprivation among some pilots of the F-22, built by Lockheed Martin Corp., were caused by problems with the oxygen supply delivered to pilots, not oxygen contamination.
To fix those problems, the Air Force will replace a valve in flight suits that had restricted breathing at high altitude and has increased the oxygen supply to pilots by removing an air filter.
"After receiving assurances that these corrective measures would minimize hypoxia-like events in the F-22, (Defense Secretary Leon Panetta) approved the Air Force planned sequence of actions to remove flight restrictions over time. This process starts today," Little told reporters.