Model Manufacturer Launch date Launch vehicle COSPAR ID Comments Satcom 1 RCA Astro Electronics December 12, 1975 Delta 3000 1975-117A Satcom 2 RCA Astro Electronics March 26, 1976 Delta 3000 1976-029A Satcom 3 RCA Astro Electronics December 7, 1979 Delta 3000 1979-101A Failure during GTO (currently in non-geosynchronous orbit) Satcom 1R RCA Astro Electronics April 11, 1983 Delta 3000 1983-030A Replaced Satcom 1 Satcom 2R RCA Astro Electronics September 8, 1983 Delta 3000 1983-094A Replaced Satcom 2 Satcom 3R RCA Astro Electronics November 20, 1981 Delta 3000 1981-114A Replaced Satcom 3 Satcom 4 RCA Astro Electronics January 16, 1982 Delta 3000 1982-004A Satcom 5 RCA Astro Electronics October 28, 1982 Delta 3000 1982-105A Also called Aurora 1, still on 105.2'W (2006) Satcom 4R Hughes November 8, 1984 STS-51-A (Discovery) 1984-113B Launched as Anik D2, purchased in orbit Satcom C1 GE Astro Space November 20, 1990 Ariane 42P 1990-100A Replaced Satcom 1R Satcom C3 GE Astro Space September 11, 1992 Ariane 44LP 1992-060B Satcom C4 GE Astro Space August 31, 1992 Delta II (7925) 1992-057A Satcom C5 GE Astro Space May 29, 1991 Delta II (7925) 1991-037A Originally called Aurora 2, replaced Aurora 1 / Satcom 5 Satcom K1 RCA Astro Electronics January 12, 1986 STS-61-C (Columbia) 1986-003B Satcom K2 RCA Astro Electronics November 27, 1985 STS-61-B (Atlantis) 1985-109D Satcom K3 GE Astro Space March 2, 1991 Ariane 44LP 1991-015A Sold during construction to SES; launched as Astra 1B Satcom K4 GE Astro Space June 10, 1992 Atlas II 1992-032A Sold during construction to Intelsat, launched as Intelsat K