First introduced in 1987, the body-stabilized Boeing 601 satellite is the best-selling large spacecraft in the world. It was originally produced by Hughes Electronics Corp., now Boeing Satellite Systems, to provide a high-power, multiple-payload satellite for such applications as direct television broadcasting to small receiving antennas, very small aperture terminals for private business networks and mobile communications.
All Boeing 601 spacecraft use the same basic bus design, so that Boeing Satellite Systems can realize efficiencies gained by production volume, tooling investments and quantity buys.
The Boeing 601 body has two modules. The first carries all launch vehicle loads and contains the propulsion subsystem, bus electronics and battery packs. The secondary module is a structure of honeycomb shelves for the communications equipment, electronics and isothermal heat pipes. This modular approach allows work to proceed in parallel, shortening manufacturing schedule and test time.
The basic 601 configuration features as many as 48 transponders and offers up to 4,800 watts. The more powerful Boeing 601HP made its debut in 1995. Its innovations included gallium arsenide solar cells, advanced battery technology and an optional xenon ion propulsion system (XIPS). The 601HP features as many as 60 transponders and provides up to 10,000 watts.
Eighty-one Boeing 601 satellites had been ordered by 2007.