[15] After a period of training, he was commissioned as an ensign in the Naval Reserve at Naval Air Station Corpus Christi on June 9, 1943, becoming one of the youngest aviators in the Navy.[16][c] Beginning in 1944, Bush served in the Pacific theater, where he flew a Grumman TBF Avenger, a torpedo bomber capable of taking off from aircraft carriers.[21] His squadron was assigned to the USS San Jacinto as a member of Air Group 51, where his lanky physique earned him the nickname "Skin".[22]
Bush flew his first combat mission in May 1944, bombing Japanese-held Wake Island,[23] and was promoted to lieutenant (junior grade) on August 1, 1944. During an attack on a Japanese installation in Chichijima, Bush's aircraft successfully attacked several targets, but was downed by enemy fire.[20] Though both of Bush's fellow crew members died, Bush successfully bailed out from the aircraft and was rescued by the USS Finback.[24][d] Several of the aviators shot down during the attack were captured and executed, and their livers were eaten by their captors.