Russian EVA breaks record – EMU troubleshooting continues

by Chris Bergin

Expedition 36 Flight Engineers Fyodor Yurchikhin and Alexander Misurkin have completed the first of two spacewalks to prepare the International Space Station (ISS) for the arrival of the Russian Multipurpose Laboratory Module (MLM). Their extended EVA broke the spacewalk duration record for a Russian spacewalk. Meanwhile, the investigation into the leak in Luca Parmitano’s spacesuit is continuing.

RS-34 – CLICK HERE FOR LIVE COVERAGE:

Yurchikhin and Alexander Misurkin were tasked with the installation of equipment for the arrival of the new Russian module, with another EVA to follow next week.

The 172nd EVA support of space station assembly and maintenance, this was the seventh of veteran Yurchikhin’s career and the second for Misurkin.

Yurchikhin was wearing a Russian Orlan suit bearing red stripes, while Misurkin donned a suit with blue stripes. Misurkin’s suit was also equipped with an American helmet camera to provide close up views of the work he will be performing outside the station.

The two cosmonauts exited the Pirs airlock at 10:36 am Eastern, tasked with continuing to route power and Ethernet cables for the future arrival of the Multipurpose Laboratory Module.

Proton FailureThis new module will be launched aboard a Proton-M rocket from the Baikonur Cosmodrome in Kazakhstan, a vehicle that is set to return to flight next month following its spectacular failure in July.

The launch – with three GLONASS-M satellites – veered off course shortly after lift-off, with the wreckage crashing back to Earth just a short distance from launch pad.

Investigators examined the remains of the rocket for a root cause and found the angular velocity sensors were installed upside down, with corrective action allowing a swift return of the Russian workhorse that will eventually loft the MLM to the ISS.

Russian EVAThe first task of the spacewalkers once they had exited the Pirs docking compartment was to deploy the Strela boom which is a portable, telescoping crane that can move gear and a spacewalker outside the station.

They used Strela to install connector panels and gap spanners outside the Zarya and Poisk modules.

Yurchikhin and Misurkin also installed the Vinoslivost experiment panel on Poisk which exposes different materials to the space environment.

During the EVAThey then routed power and Ethernet cables outside Zarya and Poisk before stowing the Strela boom.

Although the EVA was expected to last six and a half hours, the duo saw their work on the outside of the Station extended past the seven hour 16 minute mark, beating the previous record duration EVA that took place in 1990 on the Mir space station, required to repair insulation blankets that were flapping loose on the Soyuz TM-9 reentry vehicle.

EVA-34 closed out on the seven hour, 29 minute mark, to set the new Russian record.

The world record was registered during STS-102 in March of 2001, when Jim Voss and Susan Helms conducted an eight hour 56 minute spacewalk – although a large part of the EVA was registered from inside Discovery’s airlock.

EVA-23 Investigation:

Meanwhile, NASA’s Anomaly Resolution Team (ART) are continuing to investigate the cause of the water leak in Luca Parmitano’s suit that terminated EVA-23 on July 16.

EMU SchematicThe ART have so far met seven times, with with the reviews of previous troubleshooting results and on-orbit data indicating that the most likely cause of the vent loop water leak relates to a blocked or clogged Water Separator Pilot Tube, a blocked condensate water relief valve, or a blocked condensate water line filter.

Specifically, engineers have determined that the EMU 3011 water separator loop is allowing excessive amounts of water to enter the ventilation loop.

“A leading theory of a clogged water separator loop in EMU 3011 has been postulated by the technical community that could explain how water was introduced into the vent loop once in EVA,” noted expansive rolling updates on the dedicated investigation section in L2.

While the investigation continues, the EVA Project Office verbally presented an overview of the “Road To” Plan to be able to conduct a contingency EVA via the two remaining EMUs on the Station.

EMU Being TestedDuring recent testing, the crew performed tests of Extravehicular Mobility Units (EMUs) 3005 and 3010 to check the status of the condensate water transport loops and assess for leakage into the vent loop.

“During the test setup, the crew was unable to successfully connect the Station Support Computer (SSC) to either EMU to collect high rate data,” added notes.

“After discussions on the ground, the crew pressed with the test with the nominal telemetry data. Additional onboard troubleshooting was unsuccessful, and ground teams are attempting to recreate the issue in the lab. The high rate data will likely be needed for follow on troubleshooting for EMU 3011.”

Should the ISS require a contingency EVA, an immediate risk discussion will be held with ISS senior management to discuss the residual risk.

Cygnus arriving at the ISS' KOZ (Keep Out Zone).Investigation notes also added that some EMU elements – namely ground-built Helmet Absorption Pads (HAPs) – will ride uphill on an upcoming Soyuz and on Orbital’s Cygnus vehicle during its debut trip to the ISS during the ORB-D mission.

SpaceX’s next Dragon mission to the ISS – CRS-3 (SpX-3) – is also set to include a rack that will allow for EMU hardware to be launched to the ISS, with the faulty EMU 3011 then heading back to Earth.

Only the Dragon is capable of returning the EMU from the ISS.

(Images: L2’s ISS Section and NASA)

(Click here: http://www.nasaspaceflight.com/l2/ – to view how you can access the best space flight content on the entire internet)

Related Articles