365 DAY IN THE LIFE: WHEN MAJOR ANOMALIES OCCUR CHAPTER 20 tested QDs at various pressures to determine how much pressure it would take to make it too difficult for the EVA crew member to perform the necessary line movements, disconnections, and reconnections. The team designed a test with an astronaut in a sling hanging from the ceiling of a large high bay to try out the manipulation as if he were in zero- gravity. The team wanted to know how much his body moved around when he was tugging and pushing on stiff ammonia lines. The problem with this decision is one often faced with spaceflight in that it has to be based on inexact testing and analysis. It would be ideal to have the microgravity, vacuum, and thermal conditions at which the ISS is flying to understand how the hardware actually moves, However, the test subject would need to be in space for that to occur. The terrestrial test is shown in Figure 8. The Neutral Buoyancy Laboratory—a large swimming pool for EVA training—could not be used since the high-fidelity lines and QDs, of which there are precious few in existence on the ground, would corrode in the water, thereby resulting in an inaccurate reflection of the forces and actions that astronauts would have to take in space. Figure 8. Astronaut Doug Wheelock is testing fluid QDs at varying line pressures to determine which pressures make it too hard for the spacewalking crew to perform the task. Doug had performed a similar task while on a spacewalk in 2010, so he was the natural choice to perform the testing. A harness allowed his body to move left and right when he put in forces on the connectors, somewhat simulating the way it would be in space. The teams also pulled out real emergency gas masks and tested out how they could transition a crew member in a water-soaked EMU helmet to an emergency mask in the event ammonia contamination on the spacesuit is released into the ISS atmosphere after the spacesuit is inside. Water attracts the ammonia, so after repressing the airlock, the spacewalking crew member would close his or her eyes while an assisting crew immediately removed the EMU helmet, wiped the crew member’s face, and applied the emergency mask. One of the more- difficult decisions would be whether to hurry the crew members inside or have them wait longer at vacuum. When water in the helmet is not a concern, the ground would normally instruct the contaminated EVA crew members to stay at vacuum, letting any stuck-on ammonia “bake off”—a term that describes the sublimation of solid ammonia to vapor, which would effectively result in contamination lifting away from the spacesuits. If a crew member has water in his or her helmet, this might be more urgent than the ammonia contamination issue if the water moves onto the astronaut’s face. The worst case would be an astronaut who has ammonia contamination (which is fairly common) and water leaking into the helmet (which was thought to be more likely to occur if the water system was contaminated). Each case might dictate a different response, but the team did its best to generalize and write down actions that could be used for quick decision-making for the different situations. The concept of jettisoning the Pump Module (i.e., throwing it into space, where it would eventually deorbit and burn up in the Earth’s atmosphere) was one of those concepts that by Monday needed to either be pursued as the primary course of action or dropped as a concept. It was requiring a lot of work in parallel with a non-jettison option. Multiple team members came to the Team 4 meeting that day with good information and analysis related to jettisoning the degraded Pump Module. The latest trajectory analysis with new data showed that because of the mass, diameter, and external shape of the Pump Module and the various ways it could be