In 1970, Hughes Aircraft Company (HAC) Space and Communications Group offered the first standardized

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioi ...

: the HS 333 design. A spinning satellite, it was based on previous one-design satellites like

Intelsat I Intelsat I (nicknamed Early Bird for the proverb "The early bird catches the worm") was the first commercial communications satellite to be placed in geosynchronous orbit, on April 6, 1965. It was built by the Space and Communications Group of ...

. HAC built eight of these 300

watt The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James ...

, 12 channel single antenna satellites between 1970 and 1977.Hughes Aircraft Corporation, Space and Communications Group, SBS F6 Prime sales brochure, 1985

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 Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min, or with the notation min−1) is a unit of rotational speed or rotational frequency for rotating machines. Standards ISO 80000-3:2019 defines a unit of rotation as the dimensionl ...

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:

Design

Satellites

References

See also