Spacewalk canceled after space suit coolant leaks

Sailing in the International Space Station’s airlock module, “Quest,” veteran spacewalkers Tracy Dyson and Mike Barratt were preparing to blast off Monday to complete a spacewalk that was canceled June 13 when Dyson reported a significant water leak from her suit’s cooling system, saying “there is literally water everywhere.”

The leak was stopped when Dyson reconnected an umbilical that supplies the station’s power, cooling water and oxygen. The airlock was crushed, its inner hatch opened and the astronauts moved to the inner compartment of the airlock where the crewmates were standing by to help them out of their bulky suits.

NASA said Dyson and Barratt were never in any danger.

The leak began shortly after the crew switched their spacesuits to battery power at 8:46 a.m. EDT to officially begin the planned six-and-a-half-hour spacewalk. Moments after switching to battery power, the cooling water on Dyson’s suit began to spray.

“Oh my god,” Dyson said when he noticed the water coming out.

“Oh, wow,” Barratt admitted.

“Water is leaking from my SCU (service and cooling umbilical), guys,” Dyson told the flight controllers. The umbilical supplies cooling water, oxygen and electrical power until the crew member detaches to exit the airlock.

“There’s a lot of water flowing,” Dyson said, a moment later adding, “there’s literally water everywhere. … I’ve got ice all over my helmet.”

The umbilicals were reconfigured and the flow stopped. After closing the outer hatch of the airlock, the compartment was depressurized so that the spacewalkers could return to the station.

While they never sailed outside, Dyson and Barratt were credited with a 31-minute spacewalk. This is the time between switching their spacesuits to internal batteries and reconnecting them to station power.

Barratt already held the record for the shortest spacewalk on record, 12 minutes in a vacuum inside the Russian segment of the station in 2009, when he and cosmonaut Gennady Padalka installed a docking mechanism instead of a cap.

That record still stands.

“And Mike, you already have the shortest EVA that I know of, but that doesn’t count today. So your old record still stands,” said astronaut Steve Bowen from mission control.

“Great,” laughed Barratt. “To herald this, it was the shortest complete — and most successful — EVA on record.”

Dyson has now logged four spacewalks lasting a total of 23 hours and 20 minutes, while Barratt’s total across three EVAs is five hours and 37 minutes. The station’s total spacewalk time through 271 EVAs is a total of 1,715 hours 56 minutes, or 71 days 11 hours 56 minutes.

It was the second spacewalk in a row to be canceled before the astronauts exited the airlock.

Dyson and astronaut Matthew Dominick originally planned to perform the same excursion on June 13, but the spacewalk was canceled after Dominick reported a “discomfort issue” with the suit. No details were given.

Dyson and Barratt were already prepared for a second spacewalk, or EVA, and NASA managers decided to keep the same lineup for Monday.

The exit’s goals were to retrieve a malfunctioning radio transmitter and antenna package, known as a radio frequency array, or RFG, that had defied two previous attempts to remove it from a storage platform.

Dyson also planned to sweep several targeted areas near the US station’s airlock and several vents in an effort to collect samples of any microorganisms that might have managed to survive the extreme temperatures, radiation and vacuum of open space.

If researchers find any such organisms after the samples are returned to Earth, it will help engineers find ways to prevent similar terrestrial bio-fouling on Mars during future missions to the red planet.

If the spacewalk had gone well, NASA planned to organize another EVA on July 2. It is not yet known how the water leak issue may affect the spacewalk schedule or what will need to be done to correct the problem.