English: A North American Aviation A3J-1 Vigilante (Navy serial number 147858/NASA tail number 858) arrived from the Naval Air Test Center, Patuxent River (Maryland, USA), on 19 December 1962 at the NASA Flight Research Center (now Armstrong Flight Research Center, Edwards, California). The Center flew the A3J-1 in a year-long series of flights in support of the U.S. supersonic transport program. The Center flew the aircraft to determine the let-down and approach conditions of a supersonic transport flying into a dense air traffic network. These flights followed two flight plans that were based upon earlier NASA Flight Research Center studies, one for a variable-sweep wing configuration and the other for a delta-wing configuration. NASA Flight Research Center test pilot William H. Dana made approximately 21 flights along federal airways that entered Los Angeles. With the completion of the research flights, the Center sent the A3J-1 back to the Navy on 20 December 1963.