420th Flight Test Flight The 420th Flight Test Flight ( 420 FLTF ) is an inactive United States Air Force Reserve squadron . It was last assigned to the 413th Flight Test Group of Air Force Reserve Command at Phoenix - Mesa Gateway Airport , Arizona , where it was inactivated on 31 October 2007 . The flight was first active during World War II as the 420th Night Fighter Squadron . The squadron served from 1943 to 1944 as an Operational Training Unit for night fighter aircrews . The 420th Air Refueling Squadron was activated under Tactical Air Command in 1954 but moved to England , where it served under United States Air Forces Europe until being inactivated as Strategic Air Command assumed the role of single manager for USAF air refueling . In 1985 the night fighter and refueling squadrons were consolidated into a single unit . The 6520th Test Squadron was organized in 1989 by Air Force Systems Command . In 1992 , as the USAF eliminated Major Command controlled ( MAJCON ) units , the 6520th was consolidated with the 420th and redesignated the 420th Flight Test Squadron . The squadron was inactivated as a regular unit in 1997 , but was activated four years later in the reserves as the 420th Flight Test Flight . History . World War II . The squadron was first established in mid - 1943 as the 420th Night Fighter Squadron , a defensive Night Fighter interceptor squadron at the Army Air Forces School of Applied Tactics ( AAFSAT ) at Orlando Army Air Base , Florida . Night fighter combat over the skies of England made the USAAF aware of the need for night air defense training and tactics development . AAFSAT was ordered to develop a training program to produce pilots with night fighting skills . The 420th Night Fighter Squadron was designated as the Operational Training Unit ( OTU ) at Orlando for the training program . AAFSAT ' s immediate requirement was to train night fighter pilots for two operational squadrons that were destined for Hawaii and for Panama . However , initially the training program could not be carried out due to a lack of training aircraft . The school acquired a collection of aircraft from AAF Training Command . Only a few Douglas P - 70 Nighthawk s were modified for night operations . Production delays at Northrop for the P - 61 Black Widow fighter aircraft required the unit to use what it had until the first YP - 61s were received in early 1944 . In January 1944 the entire program moved to Hammer Field , California and was placed under IV Fighter Command . The move placed the squadron near Northrop manufacturing facility at Hawthorne , California and most programmed P - 61 squadrons were planned for operations in the Pacific and China Burma India Theater s . In March 1944 the 420th was disbanded when the AAF found that standard military units , based on relatively inflexible tables of organization were proving less well adapted to the training mission . Accordingly a more functional system was adopted in which each base was organized into a separate numbered unit during a reorganization of units in the United States . The squadron ' s personnel and equipment were transferred to Squadron A of the 450th Army Air Forces Base Unit ( Night Fighter Replacement Training Unit ) . Cold War . The 420th Air Refueling Squadron was activated in 1954 by Tactical Air Command to provide dedicated air refueling for TAC bomber s , fighter s , and fighter bombers . The 420th was activated at Alexandria AFB , Louisiana and was the first TAC air refueling squadron . The squadron received KB - 29Ps fitted with the refueling boom . In 1955 the unit deployed to United States Air Forces in Europe and was based at RAF Sculthorpe , Norfolk , England to provide air refueling for USAFE squadrons . However , the KB - 29s were simply too slow to refuel jet fighters . The increasing performance of operational fighters made it necessary to boost the performance of the tankers , and this was done by re - equipping with the KB - 50 Superfortress in 1957 which provided greater speed to refuel jet aircraft . KB - 50s were modified to KB - 50J configuration in 1958 which added a J - 47 turbojet engine underneath each wing in place of the auxiliary fuel tanks to increase the speed of the aircraft . The KB - 29P was phased out in 1958 . Unfortunately , the elderly KB - 50Js began to deteriorate almost as soon as they were delivered , and due to a chronic parts shortage TAC was forced to resort to cannibalization to keep the retrofitted tanker aircraft flying . Landing gear malfunctions were frequent , and many parts started to break simply because of old age . More and more maintenance had to be performed in order to keep the aircraft flying . By 1963 the squadron ' s aircraft began to be phased out , the mission being taken over primarily by Air National Guard Boeing KC - 97 Stratotanker s . rotating to Europe under Operation Creek Party . The squadron inactivated in early 1964 and its KB - 50Js were sent to the Military Aircraft Storage and Disposition Center at Davis - Monthan AFB . Arizona . B - 2 Spirit Flight Testing . Air Force Systems Command activated the 6520th Test Squadron in March 1989 at Edwards AFB , California . Its mission was the pre - operational testing of the B - 2 Spirit stealth bomber . The B - 2 was first revealed to the public on 22 November 1988 , when AV - 1 ( 82 - 1066 " Spirit of America " ) was unveiled at Air Force Plant 42 near Palmdale , California . At this time the aircraft was still not ready for its first flight . Taxi tests began on 10 July 1989 . The B - 2 finally made its first flight on 17 July 1989 from Palmdale . The flight lasted 112 minutes and ended with a landing at Edwards and delivery to the 6520th . After carrying out initial tests , AV - 1 was used for radar cross section tests . In early 1993 , AV - 1 was placed in long term storage to await upgrading to full service configuration prior to joining the operational fleet . The second test aircraft ( AV - 2 , 82 - 1067 " Spirit of Arizona " ) flew for the first time on 19 October 1990 from Palmdale , landing at Edwards AFB . It was heavily instrumented and served as the loads test aircraft . AV - 3 ( 82 - 1068 " Spirit of New York " ) took to the air for the first time on 18 June 1991 . It was the first radar and navigation test aircraft . AV - 4 ( 82 - 1069 " Spirit of Indiana " ) followed on 17 April 1992 , and AV - 5 ( 82 - 1070 " Spirit of Ohio " ) on 5 October 1992 . These two planes were used for avionics and weapons testing . The first bomb to be tested with the B - 2 was a 2000 - lb Mk 84 , which was dropped from AV - 4 on 12 September 1992 . AV - 5 was the intended for armament , climactic , and low - observability testing . On 1 October 1992 , the 6520th Test Squadron was consolidated with the 420th Air Refueling Squadron . The next day the consolidated unit was renamed the 420th Test Squadron . The last development aircraft , AV - 6 ( 82 - 1071 " Spirit of Mississippi " ) flew on 2 February 1993 . It was used for technical order validation and for further weapons and avionics testing . By January 1995 the six B - 2s had logged more than 2300 hours in the air in more than 490 flights . Terrain - following certification flights were undertaken by AV - 4 in September 1996 . By January 1997 , the B - 2 had reached limited operational capability and testing at Edwards was phased down . B - 2 flight testing was transferred to the 419th Flight Test Squadron and the squadron was inactivated at the end of 1997 . T - 38 Talon Flight Testing . The 420th was reactivated in 2001 at Phoenix - Mesa Gateway Airport , Arizona ( formerly Williams AFB ) as the 420th Flight Test Flight . The flight acted as a T - 38 Talon functional check flight organization . The 420th replaced Operating Location E of the 622d Regional Support Group , which originally stood up in May 2000 . After the 413th Flight Test Group was created at Robins Air Force Base , Georgia , transferred to the group in 2003 . The unit supported the T - 38C avionics upgrade program by flying depot - level test sorties and acceptance check flights after the cockpit upgrades were completed . In addition , pilots would pick up aircraft and bring them to Mesa for upgrade at a Boeing facility and then deliver them after the work was complete . The squadron was inactivated on 30 October 2007 due to budget reductions . Lineage . 420th Night Fighter Squadron 420th Air Refueling Squadron 420th Flight Test Flight