EVAs in August

[GordonD]

26 AUGUST

 

2002 Valeri Korzun & Sergei Treshchyov (ISS Expedition 5)

 

Duration 5 hr 21 min

 

The start of the EVA was delayed when a minor pressure leak was detected in the hatch between Zvezda and Zarya, but once this was dealt with the cosmonauts mounted a frame on Zarya which would allow temporary stowage of equipment on future spacewalks. They also installed four fairleads, devices that would hold tethers in place so they could be routed more efficiently. Next, they swapped out Japanese experiments measuring the effects of the space environment on various pieces of engineering equipment. With time in hand, they replaced the Kromka deflector plate, a task left incomplete by Korzun and Whitson ten days earlier, and also installed two amateur radio antennae on Zvezda to improve communications with ham operators on Earth.

 

Fourth and last EVA for Korzun; his career total amounts to 22 hr 21 min. Treshchyov's only EVA.

[GordonD]

27 AUGUST

 

No EVAs on this date.

[GordonD]

28 AUGUST

 

No EVAs on this date.

[GordonD]

29 AUGUST

 

No EVAs on this date

[GordonD]

30 AUGUST

 

2012 Sunita Williams & Akihiko Hoshide (ISS Expedition 32)

 

Duration 8 hr 17 min

 

The astronauts began by connecting a power cable in preparation for the future arrival of a Russian laboratory module, then moved onto the EVA's primary task: the replacement of a Main Bus Switching Unit on the S0 Truss. The failed unit was successfully removed and transferred to a temporary stowage area, but then they ran into problems when they encountered difficulties driving home the bolts to secure the new unit in position. Eventually the work was abandoned and the unit was tied down with a tether for another attempt on a future spacewalk. By this time the EVA was already the third-longest in history (the planned duration was only six and a half hours) so the final objective, replacing a camera on the manipulator arm, was not attempted.

 

Fifth EVA for Williams; first for Hoshide.

[GordonD]

31 AUGUST

 

1985 James van Hoften & William Fisher (STS-51I)

 

Duration 7 hr 20 min

 

Back in April, Shuttle mission STS-51D had deployed the Syncom-IV-3 comsat (also known as Leasat 3) but it had failed to power up, despite an unrehearsed EVA to attach two jury-rigged plastic tools to the end of the manipulator arm in an attempt to trigger the satellite's activation switch. Now, after four months of intensive planning, a repair mission was launched. It was hoped that a single EVA would suffice, but engineers had determined that two would be required, and the flight schedule was amended. To add to the problems, it was discovered that fuses had blown in the Orbiter's manipulator arm, forcing operator Mike Lounge to position its joints one at a time with no computer assistance. When the EVA began, van Hoften placed his feet in the restraint at the end of the arm, and Lounge carefully lifted him up to within reach of the satellite, a 4.3m-diameter cylinder. This was rotating very slowly, so he found it easy to attach a bar that would enable him to halt the spin by hand, after an initial attempt when the bar did not fit properly. Once Syncom was stable, the astronauts installed plugs to 'safe' it, ensuring it would not suddenly power up while they were working on it, then fitted a bypass cable harness to work around the faulty switches. Some engineers had feared that the satellite's batteries might have frozen but this turned out not to be the case. When prompted, Syncom's omnidirectional antenna popped up, showing that the repair had been successful. The EVA ended with the satellite back in safe mode, attached to Discovery's manipulator arm.

 

Third EVA for van Hoften; first for Fisher