STS payload ground handling mechanism at John F. Kennedy Space Center

The payload ground handling mechanism (PGHM), which lifts payloads out of the payload canister that brings them to the launch pad, is described. The PGHM then loads the payloads into the orbiter through the open payload bay doors. The challenge was to provide this capability in time for space shuttle mission 31-A. Meeting this STS requirement was considerably more challenging than using the stacking method for loading payloads on top of expendable vehicles. The new mechanism and its main features are discussed.