The spacecraft was capable of transmitting voice, data, facsimile and Telex messages to and from ships at sea through special shore stations at Southbury, Connecticut and Saint Paul, CA, which were interconnected with existing domestic terrestrial networks.

The system was initially utilized primarily by the U.S. Navy, with a limited amount of satellite capacity provided in different frequency bands (L band), through separate satellite transponders, for maritime communications services to commercial entities and other interested users.

At such time as the Navy's requirements terminate (late 1970s) substantial satellite capacity will become available for commercial maritime purposes.

It was placed in geosynchronous orbit at 15 degrees west and using propulsion FW-5.

Marisat 1 was launched by a Delta rocket from Cape Canaveral Air Force Station, Florida, at 22:32 UTC on February 19, 1976.