Astronauts handle explosives on daring spacewalk

Tag : Socket Wrench

In a daring spacewalk, two space station astronauts cut into theinsulation of their descent capsule Thursday and removed anexplosive bolt that could have blown off their hands withfirecracker force.
Spacewalkers Sergei Volkov and Oleg Kononenko managed, in the end,to safely disconnect the bolt from the Soyuz capsule that will betheir ride home this fall. They immediately slid it into ablast-proof container.
"It is in," one of the Russian spacewalkers called out.
"Good. Thank God," someone replied in Russian.
Before the spacewalk, flight controllers in Moscow assured Volkovand Kononenko that the bolt would not explode and that theunprecedented job would help ensure their safe return to Earth inthe Soyuz. Nonetheless, Mission Control repeatedly urged them to becareful as they worked near the explosives.
"Take your time," Mission Control warned. "Be careful; be careful,please."
NASA said that its own engineers were convinced the spacemen wouldbe in no danger, and that it would be all right for them to put theexplosive bolt in the blast-proof canister and take it into theinternational space station for eventual return to Earth.
The past two Soyuz descents have been steep, off-course andbone-jarring, and the Russian Space Agency wants to avoid theproblem when Volkov and Kononenko fly home in October. The capsulecurrently docked at the space station ferried up the two Russiansin April.
Kononenko used a serrated knife to cut away the thick shinyinsulation surrounding the bolt _ a tool normally shunned byspacewalkers because of the possibility of piercing theirpressurized suits or gloves. It was a messy job, with shreds of themultilayer insulation floating every which way.
Next, the astronauts installed devices to eliminate staticelectricity, struggling at times in the small, cramped area.Finally, four hours into the spacewalk, Volkov pulled out a socketwrench and removed the 3-inch pyrotechnic bolt, one of 10 used toseparate two parts of the module during re-entry.
During Soyuz descents this past April and in October 2007, thesetwo sections did not separate properly, leading to so-calledballistic entries that subjected the crews to far higher gravityforces than normal.
Russian engineers suspect some of the explosive bolts did not fire.By disabling the bolts in this suspect location, there should be nomechanical hang-up during the October descent, officials said.
The lone American on board, Gregory Chamitoff, was inside the Soyuzfor the entire six-hour spacewalk in case an emergency required thetwo Russians to join him in the capsule. Chamitoff took books,music and a laptop computer with him to while away the time, andcould hear everything that was going on.
Each pyrotechnic bolt has the force of a large M-80 firecracker,NASA officials said.
A high-ranking flight director at Russian Mission Control outsideMoscow told the crew Wednesday that the bolt could withstand shocksof up to 100 times the force of gravity and would not fire, even ifthey hit it with a big hammer. "You should not be concerned atall," he said.