T Syncom satellites were developed for the NASA Goddard Space Flight Center by the Hughes Aircraft Company. Syncom was designed to operate at synchronous altitude as a spin-stabilized satellite with redundant communications, telemetry and command, and attitude control subsystems. The spacecraft nominal launch weight is 147 Ib. The initial orbital weight after apogee boost is 85.5 Ib. With this weight limitation, it was not feasible to provide experiments such as radiation environment, etc., onboard the spacecraft. Syncom 2 was launched from Cape Kennedy by a ThorDelta booster on July 26, 1963, with an orbital inclination of 33°. Syncom 3 was launched by a thrust-augmented ThorDelta booster (TAD) on August 19, 1964. The higher thrust capabilities of the TAD, coupled with two yaw maneuvers, enabled Syncom 3 to be a synchronous equatorial satellite. Syncoms 2 and 3 continue to operate on essentially a 100% utilization basis with no loss in operational performance.