HS-333


In 1970, Hughes Aircraft Company Space and Communications Group offered the first standardized satellite: the HS 333 design. A spinning satellite, it was based on previous one-design satellites like Intelsat I. HAC built eight of these 300 watt, 12 channel single antenna satellites between 1970 and 1977.

Design

The early satellites were designed with cylindrical bodies to maximize the size of the satellite that could fit inside of the rocket's nose cone or fairing which was also round. The early design satellites also relied on spinning at about 30 rpm for stability in orbit. The spinning satellite is a gyroscope.
Several parallel decks, including the top and bottom, were used to mount the propulsion, attitude control, communication, Telemetry & Command, and power equipment. The upper deck or top of the satellite contained the payload antenna and the T&C antenna.
The outer surface of the cylindrical body was covered with solar cells to generate power for operating the satellite's electrical equipment. Batteries provide power during eclipse, when the satellite is in the shadow of the earth. The batteries are recharged by excess power from the solar array.
The HS 333 was 1.8 m in diameter and nominally 3.3 m high. The solar array and batteries provided sufficient power over the satellites 7 year design life to power the 190 W payload and 233 W spacecraft equipment. The payload contributed 54 kg of the HS 333's 146 kg dry mass.

Satellites

Eight HS-333 satellites were launched:
SatelliteOperatorLaunch date
Carrier rocketMassLongitudeRetirementRemarks
Anik A1 Telesat Canada
01:14:03		Delta 1914
Anik A2 Telesat Canada
23:47:03		Delta 1914
Westar 1 Western Union
23:33:03		Delta 2914
Westar 2 Western Union
23:53:00		Delta 2914
Anik A3 Telesat Canada
23:35:26		Delta 2914
Palapa A1 Perumtel
23:31		Delta 2914
Palapa A2 Perumtel
23:16		Delta 2914
Westar 3 Western Union
00:20		Delta 2914