More Discovery External Tank GUCP Measurements and Stringer Crack Analysis

Over the weekend at Launch Pad 39A at NASA’s Kennedy Space Center in Florida, technicians will take additional measurements to ensure the best possible alignment of the newly installed ground umbilical carrier plate (GUCP) on space shuttle Discovery’s external fuel tank. Teams will evaluate data and now expect to begin installing the flight seal and quick disconnects on Monday, Nov. 15.

Engineers met today to discuss upcoming work to repair cracks in Discovery’s external tank intertank section. During foam removal and inspection of adjacent stringers to the one with two 9-inch cracks, technicians today identified an approximately 3-inch crack on the left-hand adjacent stringer. This was not an unexpected result since the load was most likely transferred to the adjacent stringer when both sides of the original stringer cracked during tanking operations for Discovery’s scrubbed launch attempt on Nov. 5. Teams will build and use existing structural math models to understand the loading at the interface. Stringers are aluminum support strips on the outside of the external tank that form the section between the inside liquid oxygen tank and the liquid hydrogen tanks.