An F-22 Raptor takes off for a training mission at Joint Base Pearl Harbor-Hickam, Hawaii. The aircraft was flown by Col. Terry Scott during his fini-flight, which is the ceremonial final flight of an Air Force pilot. Scott is retiring from the Air Force after 33 years of combined enlisted and commissioned service. (U.S. Air Force photo by Staff Sgt. Alexander Martinez/Released) Constrained for funds and facing rapidly improving potential adversaries, the US Air Force (USAF) is grappling with