550th Fighter Squadron The 550th Fighter Squadron is an inactive United States Air Force unit . Its last assignment was with 56th Operations Group , being inactivated at Luke Air Force Base , Arizona on 30 March 1995 . The units World War II predecessor unit , the 550th Night Fighter Squadron served with Thirteenth Air Force in the Southwest Pacific Theater , engaging in combat over the Dutch East Indies and Philippines in 1944 and 1945 . History . World War II . The 550th Night Fighter Squadron was the last P - 61 Black Widow squadron trained during World War II , receiving its training in California rather than in Florida . Assigned to Thirteenth Air Force , arriving at Hollandia in the Dutch East Indies part of New Guinea in December 1944 . Deployed to forward bases at Middleburg and Wama , but during 1945 aerial targets became increasingly rare , and the squadron turned to long range night - time intruding , carrying out the same mission as the aircraft they had originally been stalking , the P - 61 ' s long range enabled attacks on Japanese targets as far as the Philippines . Moved to newly established bases in the Philippines in March , and the 550th NFS began flying a number of direct infantry support missions , helping with the battle on Negros . Aircraft were modified in the field to accommodate 5 - inch High Velocity Aircraft Rockets ( HVAR ) . Rockets were used in the squadron ' s night intruder missions . Performed joint operations with the 418th and 418th NFS during the invasion of Balikpapan on the east coast of Borneo in late June 1945 ; staging out of Sanga Sanga in the Sulu Archipelago . Performed pre - invasion intruder strikes , expending large numbers of 5 - inch HVARS , and performing night air defense over the invasion Naval task force . Combat ending by the end of July . Personnel largely demobilized after the end of the war in September , aircraft sent to Okinawa for reassignment . The squadron was inactivated as a paper unit in California in early 1946 . Cold War . Reactivated in 1970 at Luke AFB , Arizona as an F - 4C Phantom II RTU Training Squadron , carried tail code " LA " with a red fin cap , taking over the assets of the provisional 4517th Combat Crew Training Squadron . The task of the 550th was to take experienced pilots and WSO ' s and train them to fly the F - 4 as one of the main providers of fighter pilots for Tactical Air Command and fighter forces worldwide . The 58th Tactical Training Wing served as the Replacement Training Unit ( RTU ) for F - 15A operations during the initial phases of the introduction of the Eagle into service . The wing had received its first TF - 15A Eagle in November 1974 , however problems with the reliability of the F100 engines led to the 550th TFTS not being equipped with the aircraft until 1977 . The improved F - 15C / D model arrived in 1982 for pilot training . In the late 1980s , the F - 15E Strike Eagle ground attack version of the F - 15 arrived at Luke , and the 550th was equipped with the new aircraft in March 1989 , aircraft carrying a white fin cap . Once qualified the crews were then relocated to an operational squadron at the 4th Tactical Fighter Wing located at Seymour - Johnson AFB , North Carolina . It was inactivated in November 1991 as part of the phasedown of F - 15 training at Luke . However , the 555th Fighter Squadron stationed at Luke AFB was transferred to Aviano AB , Italy in April 1994 as part of reorganization involving both USAFE and Air Combat Command . In its place the 550th Fighter Squadron was reactivated as an F - 15E RTU squadron in March , assuming the 555th ' s aircraft and personnel , with the aircraft carrying Balack tail stripe with silver wings . However , by 1994 all F - 15 air defence training had been concentrated at Tyndall AFB , Florida , with the resident Luke F - 15 Eagle squadrons reduced to just the 461st and 550th Fighter Squadrons flying the F - 15E Strike Eagle . Looking at the costs made and efficiency it was decided to be much more cost effective to make the 58th OG an all F - 16 Fighting Falcon group . Therefore it was decided that Strike Eagle training at Luke was to cease with assets transferred to the 4th Fighter Wing at Seymour - Johnson AFB , North Carolina . In late 1994 the F - 15E ' s from the 550th FS started leaving Luke AFB , and being assigned to the newly formed 333d Fighter Squadron ( RTU ) at Seymour - Johnson AFB . The last crews graduated at Luke AFB in February 1995 and the last F - 15E left Luke AFB in March closing an era of 21 years F - 15 ' s at Luke AFB . The 550th FS was inactivated on 31 March .