This page no longer updated from 31 October 2001. Latest version can be found at MACSAT

Other Designations: Multiple Access Communications Satellites. Class: Communications. Type: Military. Nation: United States. Agency: DARPA. Manufacturer: Defense Systems Inc. (now CTA).

Multiple Access Communications Satellit. The two MACSAT spacecraft are third generation DSI digital communications satellites designed to demonstrate tactical UHF voice, data, fax and video store and forward capabilities for the U. S. military. The gravity gradient boom on one spacecraft appears to have failed to deploy. The other spacecraft was used during Operation Desert Storm for message relay to and from military troops in the Gulf region. Spacecraft: Gravity gradient stabilised (approx.5 degrees control) using a 9+ meter boom and 2.3 kg tip mass. Damping achieved via hystersis rods. Z-coil used to invert the spacecraft should it stabilise upside down. Dual digital processors provide redundancy and 2.4 to 16 megabytes of data storage.16 sided cylindrical structure. Body mounted solar cells provide 10 to 17 watts of orbit average power. Redundant NiCd batteries provide 150 Whr capacity. Payload: Each satellite contains two digitally tuneable 10 watt transmitters, a 65 watt high power auxiliary receiver for spacecraft command and hardware reconfiguration, and two antenna systems. This equipment was used to conduct store and forward communications demonstrations.


Total Length: 0.4 m. Maximum Diameter: 0.6 m. Total Mass: 68 kg.

MACSAT Chronology

09 May 1990 Macsat 2; M-2 Launch Site: Vandenberg . Launch Vehicle: Scout G. Mass: 68 kg. Perigee: 600 km. Apogee: 749 km. Inclination: 89.9 deg.

Multiple Access Communications Satellite; global store and forward communications. Spacecraft engaged in research and exploration of the upper atmosphere or outer space (US Cat B).


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Last update 12 March 2001.
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© Mark Wade, 2001 .