Workers in the Payload Changeout Room, Launch Pad 39A, are on a platform in the forward cargo bay area of Space Shuttle Endeavour to search for an oxygen leak. The launch of Endeavour on mission STS-113 was postponed Nov. 10, following the completion of tanking operations, due to higher than allowable oxygen levels in the orbiter's midbody. Workers will investigate the exact location and possible cause of the leak, and effect repairs. Launch has been tentatively set for no earlier than Nov. 18, between 7 and 11 p.m. EST.