scope:

Description of Driving Event:

During the removal of the flight reaction control system (RCS) ferry plugs from the orbiter, between 1/4 and 3/4 cup of monomethylhydrazine (MMH) fuel spilled from the thruster. The liquid contacted the gloves and right shoe of the technician pulling the plug. The RCS thruster valve seals have a history of sensitivity to temperatures below 60 deg F. To limit the potential for leakage, the RCS thruster heater power unit should remain on throughout the Dryden Flight Research Facility (DFRF) safing and ferry period, including flight stopovers and KSC offload.