SLDCOM 2 & NOSS-2 1A to 1C (USA-72, USA-74, USA-76 & USA-77)

These satellites are the dispenser satellites for the NOSS-2 triplet ocean surveillance satellites. They consist of the TLD (Titan Launch Dispenser) propulsion module, the SLDCOM (Satellite Launch Dispenser Communications) UHF communication payload. After deploying the three improved Parcae (NOSS-2) payloads to a 1100 km × 1100 km, 63.4° orbit, the satellites maneuvered to a 1100 km × 9000 km, 64.3° orbit.

The improved Parcae satellites (also known by the unofficial designation NOSS-2 (Naval Ocean Surveillance System)) is the second generation of NOSS satellites. These satellites carry ELINT equipment to pinpoint and track ships and aircraft via their radio transmissions. Positions of the origin of the transmissions are determined by triangulation. Each launch consists of three satellites of similar size in the same orbit. All three satellites maneuver to stationkeep relative to one another.