F-22 oxygen issue a mystery

The Air Force Scientific Advisory Board can't explain what caused blackouts and dizziness among pilots flying F-22 Raptors. A separate investigation of the oxygen problem by Lockheed Martin is continuing. The F-22 is considered safe and continues to fly, with pilots using sensors, filters and other safety steps to mitigate potential problems. The fleet was grounded for four months last year after pilots complained of lack of oxygen. Tyndall Air Force Base, Fla., is the home of the 325th Fighter Wing, whose primary mission is to provide air training for F-22 pilots, as well as maintenance personnel and air battle managers. (Sources: multiple, including AP via Business Week, Military, 03/30/12, ABC News, Panama City News Herald, 03/29/12)