Outside the International Space Station, Expedition 55 NASA Flight Engineers Drew Feustel and Ricky Arnold conducted a spacewalk May 16 to swap out a failed cooling system component called a pump flow control subassembly (PFCS) for a spare. The PFCS is one of several on the truss structure of the station designed to regulate the flow of ammonia coolant through the cooling loops on the station to maintain the proper temperature for critical systems. It was the 210th spacewalk in support of space station assembly, maintenance and upgrades, the eighth in Feustel’s career and the fourth for Arnold.
This video is available for download from NASA's Image and Video Library: https://images.nasa.gov/details-NHQ_2018_0516_Space%20Station%20Crew%20Conducts%20Spacewalk%20to%20Change%20Cooling%20Components.html
