Launch Vehicle: >Titan III-C
First Launch: 9 February 1969
Total Weight: 1600 pounds at launch, 1424 pounds in orbit
Diameter: 111 inches
Height: 300 inches
Communications: Two hard-limiting repeaters (UHF and SHF)
Receiver channel band width: 50 KHz - 10 MHz
Transmitter frequencies: 2200 - 2300 MHz

Designed and built by Hughes Aircraft Company (now part of Boeing) under the direction of the US Air Force Space and Missile Systems Organization, the Tacsat spacecraft were the largest and most powerful communications satellites ever launched by the United States. Placed in geosynchronous orbit, the first of the huge two-story-high satellites was used experimentally by the US Army, Navy, and Air Force for tactical communications between ground stations and mobile field units, aircraft, and ships.