Sat, 30 Apr 2011 08:48:47 -0500
Technicians at NASA Kennedy Space Center’s Launch Pad 39A have drained space shuttle Endeavour’s external fuel tank of more than 500,000 gallons of super cold liquid hydrogen and liquid oxygen. Excess fuel was boiled off and teams are ensuring any remaining hazardous gasses are vented out. Technicians expect to begin the processes of accessing Endeavour’s aft by midday, in order to look at a fuel line heater associated with the auxiliary power unit (APU) system, which caused a scrub of yesterday’s STS-134 launch attempt. APUs generate hydraulic power to throttle and gimbal main engines and move the aerosurfaces.