Technicians facilitate the transfer the payload to Atlantis on Launch Pad 39-B using the Payload Ground Handling Mechanism.

Technicians facilitate the transfer the STS-106 payload to Atlantis on Launch Pad 39-B using the Payload Ground Handling Mechanism (PGHM). The circular structure shown is the docking adapter. The PGHM (pronounced pigem) is located inside the Payload Changeout Room (PCR) of each shuttle launch pad’s Rotating Service Structure. The PGHM removes payloads from a transportation canister and installs them into the orbiter. It is essentially NASA’s largest fork-lift