A technician makes his way as work begins to remove and replace the aft load control assembly 2.

At NASA Kennedy Space Center's Launch Pad 39A, a technician makes his way across a platform in space shuttle Endeavour's aft section as work begins to remove and replace the aft load control assembly-2 (ALCA-2). Located in the orbiter's aft avionics bay 5, the assembly is believed to have caused heaters on a fuel line for Endeavour's auxiliary power unit-1 (APU-1) to fail April 29 during the first launch attempt for the STS-134 mission. STS-134 will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. The mission also will be the final spaceflight for Endeavour. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett