CHAPTER 4 DAY IN THE LIFE: THE MAKING OF A MISSION 72 radiator toward its final position on the PMA3 and watch with the cameras to confirm the clearance. After plenty of margin was confirmed, the radiator was allowed to rotate freely and be “go” for the relocation. A new problem surfaced in the fall of 2009. With the decision to install the new Permanent Multipurpose Module (PMM) on the nadir side of Node 1, concern arose that the billowy insulation over the ammonia lines that ran right beside the Node 1 nadir berthing port might interfere with the module during installation. Analysis showed that the lines would pass through the PMM (Figure 6). This is what happens when late changes are made to a program that has been working on these issues for years. The team had to adapt. Figure 6. A computer-generated analysis showed the ammonia hoses (four white lines) for Node 3 (upper left) would pass through the PMM near the astronaut’s feet on their way to Node 1 (upper right). Once the issue was identified, the team came up with some modifications to the insulation and tie-down plan (Figure 7). Newly mocked-up ammonia lines were built and the crew practiced the EVA in the water at the NBL. The EVA team became concerned that the modifications were not adequate enough to ensure clearance with the PMA3. With approximately 4 months remaining before flight, it was getting late to work out some of these issues. The team convinced the ISS Program officials that it was prudent to temporarily shuffle the PMA3 to the top of the Node 2 zenith to ensure it was not in the way. This meant a lot of new, last-minute work, but this removed all the residual risk. Training for the task of moving the PMA3 also had to be quickly performed and scheduled during Expedition 22—less than a month before the mission. Fortunately, the ground and crews were becoming highly experienced at moving PMA3. Image courtesy of Art Thomason Figure 7. The spacewalking astronauts from STS-130/ISS-20A and EVA team try to figure out a new routing of the ammonia lines and the insulation using a crude mock-up of where the connectors would be on the various modules. The other half of the ammonia lines would be integrated on the third EVA. Within this time frame, Boeing engineers worked out a new plan for the ammonia lines so they would not interfere with the PMM. Elbows with 90-degree turn would be added to the lines to angle them away from the PMM. Tethers would then be used to tie the lines back. This required a great deal of analysis because the tethers had to be installed prior to the
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