|
|
|
|
|
Coolant lines connected to replacement pump BY WILLIAM HARWOOD STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION Posted: August 16, 2010 
Astronaut Douglas Wheelock successfully connected four ammonia lines to a replacement pump module, wrapping up work to replace a faulty pump that knocked one of the International Space Station's two coolant loops out of action July 31. The fourth ammonia line was connected at 10:41 a.m. and after installing positioning devices, Wheelock opened quick-disconnect valves in the lines to permit the normal flow of ammonia coolant into and out of the new pump module. To the relief of flight controllers, no ammonia leaks were spotted. "And Wheels, just to confirm, we did not see any ammonia come out today, amazingly," Oscar Koehler radioed from mission control. "So if you can confirm you saw no ammonia during any of the QD ops we are go with no ammonia tests at the end of the EVA." "OK. I did not, Oscar," Wheelock replied. "I did at one time, though, saw what I thought were just a couple of little snowflakes. But I'm not able to confirm that. There was no leak or anything." A few moments later, Wheelock showed off a cue card on his spacesuit's left wrist that thanked flight controllers and ended with the words "Game over!" While no one suspected a leak, flight controllers decided the spacewalkers would be in direct sunlight long enough during the remainder of the spacewalk to bake out any ammonia ice that might have been present before Wheelock and Caldwell Dyson return to the Quest airlock at the end of the excursion. The pump installation capped a complex three-spacewalk repair job that was required in the wake of a July 31 pump failure that took down half the space station's cooling, triggering a widespread power down to keep critical equipment from overheating. Flight controllers earlier verified the electrical health of the replacement pump and now will carry out a complex series of steps to reactivate coolant loop A, work that is expected to take several days to complete. Wheelock and Caldwell Dyson, meanwhile, planned to clean up the worksite on the S1 truss, putting insulation blankets back in place and rounding up their tools and equipment. The only remaining task is to run an extension cord from the Quest airlock to the Earth-facing side of the Unity module that needs to be in place before attachment of a cargo module during a shuttle visit in November. Wheelock and Caldwell Dyson had planned to install that cable during a spacewalk Aug. 5, but that excursion was canceled in the wake of the loop A pump failure.
|
|
|
|
|||||||||||||||||||||
VIDEO:
AMMONIA HOSES ARE ATTACHED TO THE PUMP 