The Ground Umbilical Carrier Plate or GUCP on space shuttle Endeavour's external fuel tank.

Seen in the photo is the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. Workers have removed the 7-inch quick disconnect to change out seals in the internal connection points. A leak of hydrogen at the location during tanking June 12 for the STS-127 mission caused the mission to be scrubbed at 12:26 a.m. June 13. The GUCP is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. Endeavour is scheduled to launch on its STS-127 mission on June 17 at 5:40 a.m. EDT. Photo credit: NASA/Tim Jacobs