HONOLULU - The Hawaii Air National Guard said Tuesday one of its pilots briefly experienced an oxygen deficit while flying an F-22 stealth fighter last week.
The pilot was heading back to Joint Base Pearl Harbor-Hickam from a routine training sortie when sensors indicated he wasn't getting as much oxygen as he should, said Lt. Col. Charles Anthony, a spokesman for the Hawaii Guard.
The pilot also felt dizzy. He activated the emergency oxygen system until his symptoms abated and the plane's oxygen generating system returned to normal.
The pilot landed safely after Friday's incident, the first time a Hawaii F-22 pilot has experienced hypoxia, or oxygen deprivation, Anthony said.
A medical exam cleared the pilot for duty. All 14 of the Hawaii National Guard's F-22 planes are operational, Anthony said.
The nation's F-22 fighter jets were grounded for four months last year after pilots complained of experiencing a lack of oxygen that can cause dizziness and blackouts.
An Air Force advisory panel studied the problem for seven months but couldn't identify the cause. The panel supported a plan to keep the aircraft flying with pilots using special sensors, filters and other safety precautions.
In May, Defense Secretary Leon Panetta ordered that F-22 flights remain "within proximity of potential landing locations" so that pilots can land quickly in the event they experience an oxygen-deficit problem.
The F-22 is the Air Force's most-prized stealth fighter. It was built to evade radar and is capable of flying at faster-than-sound speeds without using afterburners.
Five other bases are home to F-22s: Joint Base Elmendorf-Richardson, Alaska; Joint Base Langley-Eustis, Va.; Nellis Air Force Base, Nev.; Holloman Air Force Base, N.M.; and Tyndall Air Force Base, Fla.