In a 6-hour, 28-minute space walk, McArthur and Chiao connected 10 electrical umbilicals to provide power to heaters and conduits located on the Z1 truss, relocated and deployed two communication antenna assemblies and installed a toolbox for use during future on-orbit construction. The EVA began at 9:27 a.m. CDT and ended at 3:55 p.m. This was the seventh Space Station assembly space walk, the 51st EVA in the Space Shuttle program and the 90th by Americans in the history of the U.S. space program.
Astronaut Koichi Wakata was again at the controls of the Shuttle's robotic arm, using it to move the two astronauts around Discovery's payload bay and the Space Station. McArthur spent most of the time on the end of the mechanical arm working through the long list of cable connections and other tasks. Chiao worked from the end of the arm late in the space walk as he manually unfolded the large ISS Ku-band antenna to its deployed position. That system will be activated next February.
Both astronauts spent the first hour of the EVA deploying tools and EVA aids including foot restraints and tethers. Following the setup, the astronauts worked to connect the first six umbilical cables between Unity and the truss structure. With the first set of cables attached, McArthur and Chiao removed the S-band Antenna Subassembly (SASA) from its launch position on the Z1 truss and placed it in a temporary location where it will remain until it is moved and activated during the STS-97 mission in late November. The SASA was launched in the position where two power converter units will be installed during the third space walk on Tuesday. A second set of four cables was connected before McArthur and Chiao installed the Space to Ground Antenna (SGANT), deploying its antenna dish. The antenna dish was removed from its launch location on the Z1 truss with Chiao standing on the robotic arm as McArthur unbolted the dish assembly. The two space walkers also relocated a tool stowage box, located on the support structure for PMA-3 in Discovery's payload bay, for use during future on-orbit construction.
In tomorrow's EVA, the second team of space walkers on this flight, Jeff Wisoff and Mike Lopez-Alegria, will perform chores in helping to install the Pressurized Mating Adapter 3 (PMA3) to which Space Shuttle Endeavour will dock in early December. The two also will release latches at the top of the Z1 Truss which will be used to hold the large solar arrays that will be brought up on that flight.
The astronauts are due to start their sleep period at 9:17 p.m. CDT and be awakened at 5:17 a.m. Monday.