Fleet Satellite Communications System

FLTSATCOM (also FLTSAT) was a satellite communication system of the U.S. Navy which was used for UHF radio communications between ships, submarines, airplanes and ground stations of the Navy.

Most of the transponders on these satellites were simple repeaters with no authentication or control over what they retransmitted. This characteristic led to a subculture of radio pirates in Brazil using modified ham radio equipment to use the satellites without authorization.