INSAT-1C, Eutelsat-1 F5

INSAT-1 was a multi-purpose satellite system to provide two high-power TV broadcast and twelve telecommunications national coverage transponders, in addition to also providing meteorological services. The INSAT-1C satellite was launched on 21 July 1988 from Kourou and positioned at 93.5°E to bring the INSAT system up to full capacity. Half of the 12 C-band transponders and its two S-band transponders were lost when a power system failure knocked out one of the two buses, but the meteorological Earth images and its data collection systems were both fully operational. Earth lock was lost on 22 November 1989 and the satellite was abandoned. The reported insurance payout was $70 million.

The European Telecommunications Satellite Organization (Eutelsat) has been servicing the European community since 1977, being formally established by a multi-lateral agreement in 1985. In 1979 ESA agreed to design, build, and launch five ECS (European Communication Satellite) spacecraft to be assumed by Eutelsat after passing initial on-orbiting testing. At that time the name of each spacecraft was changed to Eutelsat 1-F1, Eutelsat1-F2, etc. Of the five ECS spacecraft, four were successfully launched (1983, 1984, 1987, and 1988) and transferred to Eutelsat. ECS 3 was lost in an Ariane-3 launch accident in 1985. As noted previously, the ECS spacecraft was derived from the OTS vehicle but with an initial mass on station of approximately 700 kg. The payload included twelve (including two spares) 14/11 GHz transponders with 20 W output power for a capacity of 12,000 telephone circuits or 10 television channels. Two solar arrays with a span of 13.8 m provided 1 kW of electrical power to the 2.2 m by 2.4 m spacecraft bus. With an anticipated working life of up to seven years, at the end of 1994 three ECS/Eutelsat 1 spacecraft were still operational at 21.5 degrees E, 25.5 degrees E, and 48 degrees E, although Eutelsat 1-F1 offered limited service due to its inclination of more than 4.5 degrees. Eutelsat 1F2 (ECS 2) was retired in December 1993.