Westar was a fleet ofgeosynchronouscommunications satellites operating in theC band which were launched byWestern Union from 1974 to 1984. There were seven Westar satellites in all, with five of them launched and operating under the Westar name.
Westar 1 (launched on April 13, 1974) has the distinction of being the USA's first commercially launched geosynchronous communications satellite, following North America's first geosynchronous communications satellite,Canada'sAnik A1 in 1972. Westar 1 was put into orbit at 99° W in theClarke belt (99° W now being the home ofGalaxy 16).
Westar 2 was launched shortly afterward on October 10, 1974. Westar 3, the first satellite to useTDMA switched data, was launched on August 10, 1979. Westars 1, 2 and 3 were built byHughes using theHS 333 platform of spin-scan stabilized satellites. They only had 12transponders on board, as opposed to laterC-band communications satellites having 24, and even contemporary satellites of the same era, such as RCA'sSatcom 1.
The later Westar 4 (launched on February 26, 1982) and Westar 5 (launched on June 9, 1982) satellites, were based on the Hughes HS 376 platform, and had 24transponders available, as opposed to the 12 on Westars 1, 2, and 3.
Westar 6, also an HS-376 based satellite, was launched fromSTS-41-B on February 3, 1984, to be put into service afterward, but the perigee kick motor (also known as thePayload Assist Module, or PAM) on the satellite failed during its approach to geosynchronous orbit, placing it at an improper and inoperablelow Earth orbit. It was retrieved on November 16, 1984, by theSTS-51-A mission ofNASA'sSpace Shuttle, where it was brought back to earth. It was then resold toAsiaSat inHong Kong, who refurbished it and relaunched it on April 7, 1990 asAsiaSat 1 aboard aLong March 3 rocket.[1] The Space Shuttle mission to retrieve Westar 6, as well as thePalapa B2 satellite which shared the launchpayload with Westar 6, was partially funded by theinsurance companies led byLloyd's of London who insured the launch of those two satellites.[2]
An on-ground spare satellite to Westar 6, Westar 6S, was in development by Western Union and Hughes when Western Union decided to divest themselves of theirtelecommunications-based assets starting in the early 1980s after suffering heavy financial losses. This resulted in Western Union selling the Westar satellite fleet and operations to Hughes in 1988.
Hughes then finished development of Westar 6S, and renamed it Galaxy 6. Modifications were made to it, and Galaxy 6 was launched on October 12, 1990.
Hughes later launched the Galaxy 4 satellite in 1992 and Galaxy 5 in 1993 to replace Westar 4 and 5 respectively, after the latter satellites reached the end of their useful life.
During the life of the Westar fleet, Western Union operated these dedicated uplink sites (now defunct, unless noted) for Westar:
