IN-ORBIT PROBLEMS experienced by three Hughes Space and Communications spacecraft are being played down as "isolated incidents" by the company.
American Mobile Satellite's HS-601, MSAT 2 spacecraft, launched in April 1995, lost power on one of its spot beams. Hughes says that this was caused by a hardware problem. The MSAT has lost 15% of its capacity, but is still able to provide a full service to subscribers.
The Indonesian Palapa C1, another HS-601, which was launched on 1 February, has been affected by a battery-power-system anomaly which has prevented its four Ku-band transponders from operating during periods of eclipse, which occur for about 90 days twice a year. This problem does not affect the spacecraft's C-band transponders, says Hughes.
Japan's JCSAT 1, an HS-393 launched in 1989, has suffered a fuel leak which will reduce its ten-year lifetime by 18 months. Hughes does not know what caused the leak and denies reports that the JCSAT 3, launched in 1995, has experienced a serious power loss. "It is operating at full power, and no loss of lifetime is expected," it says.
The JSAT 1 will be replaced by the Hughes-built JCSAT 4, which will be launched in 1997. "This is the first fuel leak to occur on a Hughes satellite in 32 years", says Hughes, which emphasises that its satellite reliability "...is still the best in the industry, at 99%".
Source: Flight International