LEASAT

The Navy's Leased Satellite (LEASAT) system consisted of three Syncom IV spacecraft leased from Hughes, which was also the satellites manufacturer. The final launch of the LEASAT program occurred in early 1990 on the Space Shuttle. The last operational spacecraft among the constellation of LEASAT communications satellites used for over a decade by the U.S. military was retired in February 1998.

LEASAT was developed to augment the Navy's Fleet Satellite (FLTSAT) Communications System. The LEASAT program was a pioneering effort to provide dedicated communications services through a long-term lease arranged by the Navy for the Department of Defense. The lease provided that the U.S. military would pay for the use of communications channels aboard each spacecraft, but not until the system was built and placed in service.

The contract also specified that the LEASAT spacecraft be launched by the Space Shuttle. Built by Hughes Communications, Inc., the "wide body" satellites were designed with a 14-foot diameter to take full advantage of the room available in the Space Shuttle orbiters' cargo bay. LEASATs were the first geosynchronous communications satellites to incorporate integral propulsion. This innovation, when coupled with the satellite's folding antenna, made it possible for the spacecraft to fit compactly in the cargo bay of the Space Shuttle, reducing launch costs. The first two LEASATs were launched into geosynchronous orbit aboard the Space Shuttle Discovery in August and November 1984. LEASAT 3 was deployed in April 1985 but failed to boost itself into geosynchronous orbit. The spacecraft remained dormant until it was retrieved and repaired in orbit by another Discovery crew four months later.

That same mission launched LEASAT 4, but that spacecraft malfunctioned and became unusable. LEASAT 5, deployed in 1990 from Space Shuttle Columbia, completed the constellation by providing four geosynchronous communications satellites approximately 90 degrees apart.

Each LEASAT spacecraft provided 13 UHF communications channels, including a 500-Khz wideband channel. The satellites provided high-priority global communications for the Fleet as well as the Air Force's Strategic Airborne Command and various Army combat units. Naval Space Command served as the operational manager for the system. UHF satellite communications for U.S. military forces are now being provided by a new constellation of UHF Follow-On (UFO) spacecraft, also built by Hughes.