CHAPTER 18 DAY IN THE LIFE: RISKY AND REWARDING SPACEWALKS—SPACE SHUTTLE MISSION STS-120/ISS-10A 314 a spare camera however, that one did not work either! The live video from Tani’s helmet camera was not detailed, but it was the best footage the ground team was going to get that day. The team had Parazynski gather a pouch with some adhesive tape while at the airlock. The crew was able to use the tape to pick up shaving samples by touching the adhesive side to the shavings. These could not be analyzed until they were brought home after the mission, but they would eventually allow the engineering team to identify the source of the material. Before EVA 2 was even over, the operations and engineering teams were already thinking about what they could accomplish during this mission to continue searching for the root cause of the issue. Although the starboard SARJ could be positioned for this particular mission, analysis had not yet been completed to show there were adequate SARJ angles obtainable for the stage time frame after Discovery left and during the next shuttle mission that was planned for a few weeks later. The next mission would bring up the first ESA module: Columbus. Due to undesirable sun angles (called a “beta cutout,” as discussed in Chapter 9) starting mid-December, having to add EVAs to the stage before that mission would likely push the Columbus launch significantly until after the sun angles became more favorable for both spacewalks and dockings. A group called Team 4 was formed (see also Chapter 20) after EVA 2. Led by a flight director, Team 4 was tasked to assess whether it would be possible for the EVA crew to remove the 22 thermal covers that protected the SARJ and perform a detailed inspection of the entire SARJ to find the culprit hardware interference scraping the SARJ. This effort involved experts from across the country who were associated with the design and function of the SARJ, many of whom were also the solar array experts. The team quickly realized an inspection of this magnitude would take an entire EVA since the covers were bolted on and unbolting takes time. Team 4 started working around the clock on new SARJ inspection spacewalk procedures. The console team worked the overall plan to incorporate this EVA into the mission. EVA 3 had to continue as planned on Flight Day 8 with the P6 segment released from the Z1 section and needing to be bolted onto the port end of the truss. The new SARJ spacewalk would have to take the place of either the tile repair experiment on EVA 4 or the stage EVA 5. This was an interesting trade because the Space Shuttle Program was highly motivated to complete the tile repair experiment that required shuttle hardware/ tools, and which was to be stowed in the payload bay for return. The ISS Program needed to complete the high-priority stage tasks before the December launch of Columbus otherwise, Node 2 would not be in the right place for the Columbus attachment. In the end, this interim debate was superfluous. None of these three EVAs (SARJ, tile, or stage) would occur during STS-120. The mission was about to encounter a major setback. Flight Days 8-9 (Tuesday, October 30 and Wednesday, October 31) The EVA crew bolted on the P6 truss during EVA 3. The ground commanded the P6 arrays to slowly unfurl (i.e., deploy) from their folded- up condition (see Chapter 9) in a manner fairly similar to what had been done 7 years earlier on STS-97/ ISS-4A. An array deploys via motor in the central mast, which lifts the top half of a blanket box, resulting in the unfolding of the arrays. This re-deploy was to be done during orbital day so that crew members could directly watch and command an abort if they saw that the array was not deploying nominally. Going into the mission, the team thought P6 deploy might be tricky since other array deploys had required real-time procedural changes or even EVA assistance in the past. The day after EVA 3 was planned as somewhat light to enable the team to work on slower or fancier deploy methods if needed, based on what the team saw during the initial deploy attempt of the P6 arrays. What actually happened was jaw-dropping, and completely unforeseen. The 2B side managed to deploy without issues, but the team was able to deploy the 4B array only approximately 80% before a 0.6- to 0.9-m (2- to 3-ft) tear developed. Video showed that the array was torn along an accordion hinge line. Closer inspection revealed a smaller tear and a tangle in the guidewire that should have been assisting a smooth deploy (Figure 8). The flight control team sent a command to slowly retract the array just enough to relieve some tension so that the tear would not get