Engineering:HS-333

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Short description: Hughes Aircraft Company satellite bus
HS-333
ManufacturerHughes Aircraft Company
Specifications
Spacecraft typeSatellite
Design life7 years[1][2][3]
Launch mass560–574 kg (1,235–1,265 lb)[4]
Dry mass146 kg (322 lb)
Payload capacity54 kg (119 lb)
Power300 watts
Dimensions
Length3.3 m (11 ft)
Diameter1.8 m (5.9 ft)
Production
StatusRetired
Launched8
Operational0
Retired8
Maiden launch10 November 1972
Last launch20 August 1979
HS-376

In 1970, Hughes Aircraft Company (HAC) Space and Communications Group offered the first standardized satellite: the HS 333 design.[5] 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.[6]

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 (T&C), 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 an 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 (6 ft) in diameter and nominally 3.3 m (11 ft) high. The solar array and batteries provided sufficient power over the satellite's 7-year design life to power the 190 W payload and 233 W spacecraft equipment. The payload contributed 54 kg (119 lb) of the HS 333's 146 kg (542 lb) dry mass.

Satellites

Eight HS-333 satellites were launched from 1972 to 1979:

Satellite Operator Launch date
(UTC)
Carrier rocket[7] Mass Longitude Retirement Remarks
Anik A1[4] Canada Telesat Canada[1] 10 November 1972
01:14:03[7]
Delta 1914[1] 560 kg (1,230 lb)[1] 104°W[8]
114°W
15 July 1982
Anik A2[4] Canada Telesat Canada[1] 20 April 1973
23:47:03[7]
Delta 1914[1] 560 kg (1,230 lb)[1] 109°W[9] 6 October 1982
Westar 1[4] United States Western Union[3] 13 April 1974
23:33:03[7]
Delta 2914[3] 574 kg (1,265 lb)[3] 99°W[10] April 1983
Westar 2[4] United States Western Union[3] 10 October 1974
23:53:00[7]
Delta 2914[3] 574 kg (1,265 lb)[3] 125°W[11]
Anik A3[4] Canada Telesat Canada[1] 7 May 1975
23:35:26[7]
Delta 2914[1] 560 kg (1,230 lb)[1] 104°W[12]
115°W
21 November 1984
Palapa A1[4] Indonesia Perumtel[2] 8 July 1976
23:31[7]
Delta 2914[2] 574 kg (1,265 lb)[2] 83°E[13] 1985[13]
Palapa A2[4] Indonesia Perumtel[2] 10 March 1977
23:16[7]
Delta 2914[2] 574 kg (1,265 lb)[2] 77°E[14] 1988[14]
Westar 3[4] United States Western Union[3] 20 August 1979
00:20[7]
Delta 2914[3] 574 kg (1,265 lb)[3] 91°W[15]

References

See also