FLTSATCOM-3 or Fleetsatcom-3 (FSC-3) was a communications satellite that was used by the United States Navy for communications between aircraft, ships, submarines and ground stations. Fleetsatcom 3 gave 30 voice and 12 teletypewriter communications channels simultaneously in the UHF band. The UHF up-link was in the 290 to 320 MHz range while down-link was in the 240 to 320 MHz range. A number of channels were reserved for high priority communications by the United States Air Force. These were ground to air communications between SAC aircraft, the E-3A airborne warning and control system and elements of the presidential command structure. FSC-3's life officially ended in September 1995.
Fleetsatcom 3 was launched on 18 January 1980 at 01:26 UTC on an Atlas-Centaur rocket. The launch took place at Cape Canaveral, Florida. FSC-3 was at an inclination of 26.2 degrees. It had a periapsis of 171 km and an apoapsis of 3,524 km and an orbital period of 619 minutes.
The satellite was 1.7 meters high by 2.7 meters in diameter and a hexagonal shape. Fleetsatcom 3 had a 5.3 meter wire mesh parabolic communications antenna with 2 meter solid center sections extended from one end of the vehicle. Fleetsatcom 3 was a triaxial stabilized satellite. It utilized a reaction control wheel assembly instead of spin stabilization. The satellite produced 1.1 kW DC, using 2 three-section solar panels mounted on booms extending from the satellite. The craft used Nickel–cadmium batteries for power during solar eclipses. The FSC satellites where the heaviest communications satellite used by the United States, exceeding TacSat-1 by over 100 kg.