Jumpseat, also known as AFP-711 is reportedly a code name for a class of SIGINT reconnaissance satellites operated by the National Reconnaissance Office for the United States Air Force in the 1970s and 1980s. The program is classified, and much of the information in the open is speculative. Satellites It is believed that six Jumpseat satellites were successfully launched from Vandenberg Air Force Base on Titan IIIB launch vehicles with Agena D boosters between 21 March 1971 and 31 July 1983, the primary purpose of them being to monitor Soviet ABM radars. There was one failure, when the second satellite's Agena malfunctioned and left it in a useless orbit. The 700-kg Jumpseat satellites were manufactured by Hughes Aircraft and were inserted into highly elliptical Molniya orbits with an inclination of 63 degrees and orbital periods of close to 12 hours. These were in similar orbits to the Satellite Data System relay satellites. The successors to the Jumpseat series are the Trumpet satellites. Satellites References General Richelson, Jeffrey T. ed. U.S. Military Uses of Space, 1945-1991 Vol 1, Guide. National Security Archive. 1991. External links Entry at astronautix.com Entry at Gunter's space page Log of satellite launches from Jonathan's Space Report JUMPSEAT - SIGINT Spacecraft Series (NRO/USAF/ NSA - Program AFP-711) at GlobalSecurity.org 1971 in spaceflight 1973 in spaceflight National Reconnaissance Office satellites Signals intelligence satellites Military equipment introduced in the 1970s