May 1982:satellite digest

COSMOS 1328 1981-117A

Launched: 1149. 3 Dec 1981 from Plesetsk by F vehicle.

Spacecraft data: Not available but the mass is possibly in the region of 2 tonnes.

Mission: Probably military reconnaissance, the orbit chosen is similar to those of the two oceanographic satellites - Cosmos 1076 (1979-11A) and Cosmos 1151 (1980-5A). The previous launch of this type of satellite was Cosmos 1300 (1981-82A). The orbital plane of the new satellite was 44 degrees to the east of Cosmos 1300 at the time of launch which suggests the possibility of a system being set up with a number of operating satellites at 45 degree plane separations.

Orbit: 636 x 664 km. 97.77 min. 82.53 degrees.

COSMOS 1329 1981-118A

Launched: 0950, 4 Dec 1981 from Tyuratam by A-2.

Spacecraft data: Possibly based on Vostok manned spacecraft with spherical re-entry module, instrument unit and a cylindrical, supplementary payload at the forward end. Length about 6 m, diameter about 2.4 m. mass around 6000 kg.

Mission: Military photo-reconnaissance, recovered after 14 days.

Orbit: Initially, 233 x 261 km. 89.45 min, 65.02 degrees which decayed to 227 x 253 km by the eighth day of the flight. A series of small manoeuvres after this resulted in a higher orbit of 231 x 288 km, 89.71 min on 15 Dec.

INTELSAT 5 (F3) 1981-119A

Launched: 2330, 15 Dec 1981 from the NASA Kennedy Space Center by Atlas Centaur.

Spacecraft data: The Intelsat 5 vehicle is a box with an Earth pointing antenna array, power is supplied by a 16 m span solar array. It is 3-axis stabilised while in geostationary orbit, though during transfer orbit manoevures spin stabilisation is used. The vehicle is built up of three basic units - a support system module for spacecraft housekeeping, the communications package, and the antenna module. It has been designed specifically to fit three types of launch vehicle - Atlas Centaur, the Shuttle or Ariane. The current flight is intended to be the last using the Atlas Centaur. In addi- gion to the equipment needed to sustain orbital operations,.the support system module contains a solid propellant apogee boost motor which took the satellite from its transfer orbit to the geostationary one. The mass of the vehicle at launch was 1870 kg, which was reduced by 863 kg as a result of the apogee motor firing. A further 200 kg reduction will occur as attitude control fuel is used.

Mission: To provide radio communications through 12,000 two-way telephone channels and two colour television channels using freauencies of 4-6 GHz (wide area coverage) and 11 -12 GHz (spot beam). The satellite is owned by the 106 nation International Telecommunications Satellite Organisation which has established a system of nearly 200 ground stations around the world. Using these and the satellites, the organisation carries around 60 per cent of trans-Atlantic and trans-Pacific communications.

Orbit: Injected into a 165 x 35940 km, 633 min, 23.6 degree transfer orbit, the apogee boost motor changed the orbit to a 1440 min, equatorial drift one. The satellite was later stabilised above 15 degrees east longitude for systems checkout.

RADIO 3-8 1981-120A-F

Launched: 1059, 17 Dec 1981 from Plesetsk by C-1.

Spacecraft data: All six satellites are probably spheroidal or box shaped, around 1 m across and weighing about 40 kg.

Mission: To provide radio amateurs with spaceborne radio links. Each satellite can rebroadcast in the 10 m amateur band (29 MHz) an amateur user's signal transmitted in the 2 m band (145 MHz). Additionally, the satellites Radio 5 and Radio 7 can transmit telemetric data on demand.

Orbits: The lowest orbit is that of Radio 3: 1564 x1660 km, 118.52 min, 82.96 degrees; and the highest is Radio 8: 1653 x 1682 km, 119.77 min, 82.96 degrees. The satellites were released during the powered phase of the final rocket stage’s flight (it reached 1669 x 1680 km, 120.92 min, 82.95 degrees).

COSMOS 1330 1981-121A

Launched: 1151, 19 Dec 1981 from Tyuratam by A-2.

Spacecraft data: As Cosmos 1329.

Mission: Military photo-reconnaissance, recovered after 31 days.

Orbit: Initially 167 x 379 km, 90.00 min, 70.36 degrees, then manoeuvred several times to provide specific coverage of particular target areas. Cosmos 1330 is the first Tyuratam-launched, long life recoverable satellite not to fly at 65 degrees inclination.

MARECS 1 1981-122A

Launched: 0129, 20 Dec 1981 from Kourou by Ariane (flight L04).

Spacecraft data: MARECS’ shape is a hexagonal prism 2.5 m high and 2.0 m across. Power is provided by two solar panels. The mass at launch was 1006 kg, reducing to 563 kg in geostationary orbit after the apogee motor firing. MARECS, like INTELSAT 5, is of modular construction, though in this case only two modules are used. The service module is a derivative of that designed for ECS (Euro¬pean Communications Satellite) and provides spacecraft housekeeping, support for the two 5.2 m solar panels and three axis stabilisation by the use of momentum wheels. Station keeping is by hydrazine thrusters. The payload module with its attached antenna makes up the second part of the vehicle.

Mission: Ariane flight L04 was the last in the series of launch vehicle tests before Ariane itself goes fully operational. In addition to the MARECS satellite, the vehicle carried the fourth Ariane Technology Capsule (CAT), a Vibration Isolator Device (VID) and a scientific experiment to measure density in the ionospheric plasma surrounding the Earth (THESEE). These last three were left in the geostationary transfer orbit after the MARECS apogee motor firing. The function of CAT was to make in-flight measurements of the conditions affecting the payload from lift off until T+22 minutes when the Ascension Island tracking station lost contact, and to initiate commands to the MARECS separation devices. The VID was designed to protect the MARECS payload from launcher vibration. THESEE was conducted by a Paris youth club and selected for inclusion after a competition. Its electron probe collected density information up to 2000 km height.

Orbit:Initially a 220 x 35811 km, 638 min, 10.5 degrees transfer orbit. At the third apogee MARECS was inserted into a 1431 min drift orbit for eventual stabilisation above 26 degrees west longitude on 2 Jan 1982.

MOLNIYA-1 (52) 1981-123A

Launched: 1315, 23 Dec 1981 from Tyuratam by A-2-e.

Spacecraft data: Cylindrical body housing instrumentation and the payload, surmounted by a conical motor section. Power is provided by a "windmill” of six solar panels. Overall length is 3.4 m and the diameter 1.6 m, mass around 1800 kg.

Mission: Replacement for Molniya-1 (45). The satellite helps to operate long distance telephone and telegraph radio communications, and the broadcasting of Central television programmes to Orbita receiving stations in the Soviet far north, Siberia, the Soviet far east and central Asia.

Orbit: Initially a low parking orbit and then injected into a highly elliptical one of .481 x 38964 km, 699.4 min, 62.97 degrees. On the 15th orbit it was manoeuvred to 507 x 39842 km, 717.66 min, 62.84 degrees to provide daily repetition of the ground track.