The Air Force has temporarily canceled flight operations at Luke Air Force Base, AZ, after five incidents of pilots experiencing "hypoxia-like symptoms." (UPDATED) "According to base officials, since May 2, five F-35A pilots assigned to Luke Air Force Base have reported physiological incidents while flying," the service said in a June 9 statement. "In each case, the aircraft's backup oxygen system operated as designed and the pilot followed the correct procedures, landing the aircraft safely." The grounding is currently limited...