Two astronauts floated outside the International Space Station Thursday to install two new cameras on the front of the lab complex that will provide views of commercial crew ships during final approach and docking. The spacewalkers also planned to replace a faulty high-definition camera and close a door that is jammed open on an external instrument.
Floating in the Quest airlock, Expedition 56 commander Drew Feustel and Ricky Arnold switched their spacesuits to battery power at 8:06 a.m. EDT (GMT-4), officially kicking off a planned six-and-a-half-hour excursion.
This is the 211th spacewalk devoted to station assembly and maintenance since construction began in 1998, the sixth so far this year, the ninth for Feustel and the fifth for Arnold. Both men carried out two earlier spacewalks together in March and May.
For identification, Arnold, call sign EV-1, is wearing a suit with red stripes and is using helmet camera No. 18. Feustel, EV-2, is wearing an unmarked suit and is using helmetcam 17.
The major goal of U.S. EVA-51 is installation of two new cameras on the front of the forward Tranquility module that will provide views of Boeing CST-100 Starliner and SpaceX crewed Dragon spacecraft during final approach to a new docking mechanism mounted on the port where space shuttles once attached.
The new crew ferry ships are intended to end NASA’s sole reliance on Russian Soyuz spacecraft to carry U.S., European, Japanese and Canadian astronauts to the outpost, restoring American space transportation capability that was lost when the shuttle program ended in 2011.
Development of the new crew ships is behind schedule and it’s not yet clear when the first unpiloted test flights will be possible, but NASA hopes to begin operational crew ferry missions as soon as possible next year.
The camera work required Arnold and Feustel to route power and ethernet cables from panels on the Destiny lab module to the front of the station where two camera-boom assemblies will be installed.
“We’re taking a power cable and an ethernet cable, we hook them up outside space station and we route them out to the forward end of the space station,” said Keith Johnson, a spacewalk planner at the Johnson Space Center in Houston.
“These cameras are going to be used to view the forward end of the space station for commercial crew docking, but they also form part of an external wireless communications (network).”
After competing camera installation work, Arnold planned to climb onto the station’s robot arm for work to replace a high-definition camera assembly on the right side of the complex that is not working properly. Feustel, meanwhile, planned to venture to the far left side of the station to work on a payload mounted outside the Japanese Kibo laboratory module.
The Cloud-Aerosol Transport System, or CATS, instrument was designed to study the atmosphere using a laser firing through a large aperture door. The instrument failed earlier, leaving the door open, and Feustel planned to close and latch it down so the instrument will fit aboard a SpaceX cargo ship later for disposal.
The flight plan included several lower-priority “get-ahead” items that could be carried out if Arnold and Feustel managed to finish their primary tasks ahead of schedule.