Tim Furniss/LONDON

A Russian Proton K booster, operated by ILS International Launch Services, placed PanAmSat's PAS 5 communications satellite into orbit on 28 August after launch from the Baikonur Cosmodrome.

The launch brings to 16 the number of PanAmSat communications satellites in orbit. The constellation also includes former Hughes DirecTV spacecraft, PanAmSat having purchased the Hughes division earlier this year.

The Hughes PAS 5 weighs 3,500kg and has a 24 C-band-, 24 Ku-band-transponder. It is the most powerful satellite yet launched by the company and is the first of Hughes' HS-601 high-power craft, generating 10kW, using dual-junction gallium-arsenide solar cells. The HS-601HP represents 20% of Hughes' satellite orders.

The craft is the first commercial satellite on which a xenon-ion propulsion system (XIPS) is employed, instead of conventional liquid-propellant devices, for north-south stationkeeping manoeuvres to maintain its exact allocated position in geostationary orbit. The satellite also carries a conventional bipropellant propulsion system for orbital insertion and east-west stationkeeping, but the use of the XIPS is likely to be increased in future craft for full stationkeeping functions.

PanAmSat plans to have five more satellites placed in orbit by late 1998, including the Galaxy 8-I, which is due for lift-off in November. The PAS 5 launch marked the fifth for a commercial company by the Proton.

Source: Flight International