Extra-Vehicular Adventures: Risky Space Walking
James Oberg

All this talk about how the spacewalk repair of the shuttle’s fragile tiled heat shield is the most risky, the most daring, the most bold spacewalk in history only makes sense under conditions of amnesia, and spacewalker Steve Robinson would be just plain embarrassed to hear such assessments. He would be the last to steal credit from the forty year history of spacewalking, which does indeed continue episodes of high danger, desperation, and drama.

This doesn’t just count the very earliest walks, when men like Aleksey Leonov were almost stranded outside with a ballooning suit, or like Eugene Cernan who had to grope his way back toward the hatch while blinded with sweat and a fogged faceplate. And any walk on the lunar surface has to be rated far more dangerous than any stroll in low Earth orbit.

There have been a number of cases in which the success of a mission, or the security of the crewmen’s lives, depended on performing untested emergency procedures in space. Here are four of them.

**** June 1973: The crippled Skylab space station is repaired by spacewalking astronauts who are thrown end-over-end out into space to the very end of their safety tethers.

**** December 1977, after performing a critical repair to a docking mechanism on the Salyut space station, one cosmonaut slips loose and drifts away without a safety tether.

**** July 1990, after repairing the thermal insulation on their Soyuz return capsule, two exhausted Russian spacewalkers are trapped outside when their airlock hatch fails to close fully.

**** May 1992, an unprecedented team of THREE astronauts manually wrestle a multi-ton satellite under control.

These scary and dramatic spacewalks do not in any way diminish the drama of Steve Robinson’s “under-the-belly” excursion, but they should remind observers that his predecessors have faced and overcome even more daunting challenges under far riskier conditions.

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illustrations

STS49 images
http://images.jsc.nasa.gov/iams/html/pao/STS49.htm
best view of three
http://images.jsc.nasa.gov/images/pao/STS49/10065187.jpg

artist-concept
http://images.jsc.nasa.gov/images/pao/STS49/10065119.jpg

June 1973: The crippled Skylab space station is repaired by spacewalking astronauts who are thrown end-over-end out into space to the very end of their safety tethers.

During launch (May 14, 1973) the ‘Skylab’, America’s first space station (on its last Saturn-V booster) suffered major exterior damage when one component tore off in the hypersonic air flow. One of two main solar panels also ripped off, and the other (fortunately, as it turned out) was jammed in its folded position. Without its electrical power, the space station would be doomed.

Three astronauts on board an Apollo spacecraft reached the station on May 25 and made their first attempt to free the panel. Commander Pete Conrad flew the Apollo right up alongside the Skylab while Paul Weitz stood up in the open hatch and tugged at the wing with a 15-foot hooked pole.

Conrad was flying nearly blind, and had to do the precision task in a pressurized spacesuit since the air had been released from the cabin in order to allow the hatch to be opened. If the wing had opened in an unexpected direction it might have swatted the Apollo, causing damage to the crew’s only way back to Earth. But after half an hour of tugging, it still didn’t budge and the spacewalk repair was called off. The men entered the space station and performed other repair operations there while preparing for a more serious spacewalk.

On June 6 Conrad and the third crewmember, Joe Kerwin, left the station’s airlock with a pile of pole segments and cables that were supposed to allow the wing to be deployed. After running the cables flush along the side of the station, cutting the jammed straps, and moving across open areas without any handholds, Conrad and Kerwin applied a tug to the wing by standing up under the cable.

A few minutes of strenuous lifting led to the sudden release of the jammed wing. Both astronauts – completely out of view of Mission Control – went flying off the side of the station (in an “ass over teakettle” tumble as Conrad later recalled). They reached the ends of their safety tethers and were jerked back, eventually drifting to a safe handhold.

The station had been saved, their Apollo spacecraft remained undamaged, and best of all, nobody had been hurt. None of these outcomes was certain when the repair had begun.

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December 1977, after performing a critical repair to a docking mechanism on the Salyut space station, one cosmonaut slips loose and drifts away without a safety tether.

Once upon a space time, a Russian cosmonaut almost became a free-floating satellite, and he hadn’t even planned to go outside. It would have been quite an honor, which he would have had only a few hours of life remaining to enjoy.

In December 1977, a repair team of cosmonauts blasted off to the USSR’s newest space station, the second generation ‘Salyut-6’. A previous crew had failed to dock at the station'’ front end, so the next crew exploited one of the new station’s most revolutionary features, a ‘back door’ docking port. Once aboard the station, they prepared for a spacewalk to inspect the apparently malfunctioning forward docking port.

On December 20, pilot Yuriy Romaneko (32) and engineer Georgiy Grechko (46) entered the air-lock module of the Salyut. In the nine years since the last Soviet spacewalk, a highly sophisticated new spacesuit had been developed which combined ease in donning, long-duration autonomous life support, high arm mobility and glove sensitivity, and maximum flexibility (“one size fits all” via adjustable straps). The first actual use of such advanced equipment should normally have been at some simple task. Instead, the suits would have to be trusted without time for a cautious checkout.

After releasing the chamber’s air, they opened the front docking hatch, and Grechko moved through it into open space. There, he tethered himself, set up a lamp for night operations, and turned his attention to the latching mechanisms. His partner Romanenko, remained inside to monitor medical readings and the performance of both spacesuits.

Grechko activated the latches, inspected electrical plugs and sockets, contact sensors, guide rods, push rods, locks and sealing surfaces, and found there was not a sign of trouble. Salyut-6 was saved: the second port could be utilized by additional spaceships. Mission Control was jubilant and told the cosmonauts to wrap things up and finish the spacewalk.

The Salyut had passed out of range of Russian radio tracking stations while Grechko was preparing to return to the air lock. Suddenly he was startled to see Romanenko’s helmet stick out of the hatch: the other cosmonaut had not been scheduled to leave the airlock, but his curiosity had gotten the best of him and, on impulse, he had decided to depart from the flight plan and take a peek outside.

Grechko later recalled being amazed, then alarmed, as Romanenko drifted further and further out the hatch. Suddenly the young cosmonaut began thrashing violently, his safety line whipping around wildly. It wasn’t attached! Grechko leaned over as Romanenko passed him, and managed to grab the line. In so doing, he saved the other man’s life. Had Romanenko passed a few more feet from where Grechko was working, he would have floated out and away, free until his air ran out and he suffocated.

Once both men were inside the air lock, they debated whether or not to tell Moscow Mission Control about the incident, and decided not to. In fact, the cosmonauts didn’t tell anyone about it for months, even after their return to earth. Grechko eventually broke the news at the post-flight news conference. At the end of a prepared statement, he volunteered to comment on “some details which we did not report to earth,” as he delicately termed it.

“I hope that the flight directors will not be offended,” Grechko said carefully, “but we concealed the fact that it wasn’t just me who went out into open space, as was called for in the program, but also commander Yuriy Romanenko. It was very difficult, naturally, for him to restrain himself. It turned out that he had forgotten to fasten his safety line, and I had to grab hold of his line and hold on to him.”

The Soviet space officials may have been unhappy about this (and the story was kept out of most of the newspapers), but the cosmonauts were apparently not reprimanded and both made additional space missions. In later years, a miffed Romanenko told me that Grechko had exaggerated his role in catching hold of him as he was drifting by. But Grechko stuck by his story, and he has always been a heroic story-teller.

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July 1990, after repairing the thermal insulation on their Soyuz return capsule, two exhausted Russian spacewalkers are trapped outside when their airlock hatch fails to close fully.

Knocking on a locked door when nobody's home can be a frustrating experience. But for two cosmonauts in July 1990, the frustration was tinged with fear. They were trying to get back inside the Mir space station after a gruelling six hour spacewalk to repair the thermal blankets on the outside of their Soyuz landing capsule, and they were running low on good air. And now they couldn't get back inside.

Technically, Anatoliy (“Tolya”) Solovyov and Aleksandr (“Sasha”) Balandin were really 'inside' their closet-sized airlock chamber. Their problem was, they couldn't latch down the outer door tightly enough. After a normal spacewalk, once the door was sealed they would always open a valve to release air into the chamber, so they could then open the inner door into the pressurized station. But now when they opened the air valve, the air whistled out through the open crack around the hatch rim. "No joy", or as they say in Russian, "Neshtatnaya situatsiya" -- "Contingency situation". A millimeter-wide gap remained around the edge of the hatch.

“Were the crew’s lives in danger,” Russian TV space commentator Petr Orlov told the nation the following day. “Yes, they were.”

Fortunately, they were able to attach their suits to emergency air hoses installed in the airlock, which gave Mission Control in Moscow time to figure out what to do. The hoses fed them fresh oxygen and even more importantly ran their air through ‘scrubbers’ to remove the build-up of exhaled carbon dioxide, which is the real lurking killer on space walks.

Waiting for advice from Earth, the two cosmonauts also had time to reflect on how they had gotten into this mess. With nothing physical to do, they also had to concentrate to keep at bay a spacesuited explorer’s worst nightmare, the claustrophobia induced by the tight suits, tiny pressure chamber, and sweaty heat from their exertions.

Some years in the future, Russia’s legendary Mir space station would age ungracefully and become a dangerous place for visiting American astronauts. But in 1991 it was only five years old, in good repair, and had become the orbiting outpost where rotating teams of Russian cosmonauts had set up home in space. More than 200 miles above the Earth and soaring horizontally at five miles per second, it curved continuously around the planet, falling ‘over the horizon’ and never reaching the ground.

A special airlock at the end of one bus-sized module served as the main door into the vacuum of space. But because the crew would often be taking rocket backpacks and bulky science gear or construction material outside, the airlock would usually be packed with gear. Hence engineers decided to design the 3-foot-diameter round hatch to swing outwards. Twenty wing-nut latches around the rim were supposed to hold the door locked tight against the fifteen pounds per square inch air pressure that was normally inside the station.

This was a lousy design, unlike all previous Russian airlocks, and most US airlocks. These all opened inward and thus were normally pushed tightly closed by air pressure. In contrast, the Mir outward-hinged hatch had to fit precisely, the hinges had to remain exactly aligned, and the rim seal had to remain undamaged by bumps and scratches. But after a few months of use, the hinge became bent and the guide-pins for closing the hatch got kicked by feet or scraped by backpacks, and the hatch started to take more and more effort at the end of spacewalks to dog down the latches to make it airtight.

Then, on the spacewalk which would nearly kill them, the crew made the mistake that got them into trouble. Impatient to open the hatch at the beginning of the spacewalk, they had failed to wait for the air to entirely bleed out of the chamber. Instead, they released the last latches prematurely, and the residual air pressure had flung the hatch open violently against its hinges. Six hours later, when they had tried to close the door, they discovered that the hatch no longer fit snugly enough to be airtight.

Unable to pressurize the airlock, they were told by Mission Control to depressurize the module’s inner chamber, which had been sealed off from the rest of the station for just such a possibility. It was a struggle to get their bulky spacesuits through the hatch into the middle chamber, since the passageway was narrower than the exit door, but they had no other choice. Once inside the middle chamber, they closed its door – it was the old design that opened inwards and was held in place by air pressure – and dumped air into the chamber. Their record-breaking duration spacewalk was over, and somebody else would have to fix the outer airlock door.
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May 1992, an unprecedented team of THREE astronauts manually wrestle a multi-ton satellite under control.

American astronauts also set a spacewalk duration record less than a year later, and the reason was another spacewalking emergency. This time it wasn’t the astronauts’ lives that were in danger, but the fate of a hundred million dollar satellite.

STS-49 (in May 1992) was the first space mission for ‘Endeavour’, the shuttle built to replace the ‘Challenger’ which had been lost in January 1986. Mainly intended as a ‘shakedown cruise’, it turned out to be ideal for a rescue mission for an Intelsat communications satellite stranded in low orbit in March 1990. Space planners expected to grab the satellite during a spacewalk, attach a new rocket stage to it, and send it on its way. Once in the planned 24-hour orbit, it was to beam the 1992 Summer Olympic games in Barcelona to the whole world.

But the hand-held snare device built to grab hold of the Intelsat failed to function as hoped. On spacewalks on two consecutive days, astronauts Rick Hieb and Pierre Thuot tried several times to shove the device into the base of the four and a half ton beer-can shaped satellite. But it just wouldn’t work.

The last chance was to set aside the mechanism and just rely on muscle power. But the two men couldn’t grab the satellite by themselves, so in an overnight practice session in a water tank in Houston, fellow astronauts worked out a process where a third astronaut could squeeze into the airlock and go outside to help. Three men had never been outside on a spacewalk together, ever.

Tom Akers was that third man, using the spacesuit he had brought up for his own experiments that were scheduled to occur after the recovery. His motto in space was, “Never be in a hurry – it can be tedious, just go slow.” This was another chance to put that philosophy into practice.

Using the last of the shuttle’s maneuvering fuel, the two pilots approached the mustang satellite for a third and last time. Akers was later asked if he was worried they would fail. “That’s like being on the 18th green and thinking you’ll miss a shot,” he rebuked the journalist. “Keep your mind on what you’re doing.”

And they did. With Akers and Hieb at opposite sides of the shuttle’s payload bay, and Thuot on a platform at the end of the robot arm, they awaited the nearing, slowly spinning Intelsat. A misstep could crush their fingers or an entire hand, tearing their glove open or off entirely – and killing them from sudde3n suffocation. Hieb gave coordinating voice commands, and six hands simultaneously gripped the lower rim. Within a few seconds, they had stabilized it.

The rest was ‘routine’. Thuot plugged in the booster rocket, and after the connections checked out, the shuttle backed away to allow the rocket to fire. The men got back inside after a spacewalk lasting eight and a half hours, a record that has yet to be broken.

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December 1977, after performing a critical repair to a docking mechanism on the Salyut space station, one cosmonaut slips loose and drifts away without a safety tether.

Once upon a space time, a Russian cosmonaut almost became a free-floating satellite, and he hadn’t even planned to go outside. It would have been quite an honor, which he would have had only a few hours of life remaining to enjoy.

In December 1977, a repair team of cosmonauts blasted off to the USSR’s newest space station, the second generation ‘Salyut-6’. A previous crew had failed to dock at the station'’ front end, so the next crew exploited one of the new station’s most revolutionary features, a ‘back door’ docking port. Once aboard the station, they prepared for a spacewalk to inspect the apparently malfunctioning forward docking port.

On December 20, pilot Yuriy Romaneko (32) and engineer Georgiy Grechko (46) entered the air-lock module of the Salyut. In the nine years since the last Soviet spacewalk, a highly sophisticated new spacesuit had been developed which combined ease in donning, long-duration autonomous life support, high arm mobility and glove sensitivity, and maximum flexibility (“one size fits all” via adjustable straps). The first actual use of such advanced equipment should normally have been at some simple task. Instead, the suits would have to be trusted without time for a cautious checkout.

After releasing the chamber’s air, they opened the front docking hatch, and Grechko moved through it into open space. There, he tethered himself, set up a lamp for night operations, and turned his attention to the latching mechanisms. His partner Romanenko, remained inside to monitor medical readings and the performance of both spacesuits.

Grechko activated the latches, inspected electrical plugs and sockets, contact sensors, guide rods, push rods, locks and sealing surfaces, and found there was not a sign of trouble. Salyut-6 was saved: the second port could be utilized by additional spaceships. Mission Control was jubilant and told the cosmonauts to wrap things up and finish the spacewalk.

The Salyut had passed out of range of Russian radio tracking stations while Grechko was preparing to return to the air lock. Suddenly he was startled to see Romanenko’s helmet stick out of the hatch: the other cosmonaut had not been scheduled to leave the airlock, but his curiosity had gotten the best of him and, on impulse, he had decided to depart from the flight plan and take a peek outside.

Grechko later recalled being amazed, then alarmed, as Romanenko drifted further and further out the hatch. Suddenly the young cosmonaut began thrashing violently, his safety line whipping around wildly. It wasn’t attached! Grechko leaned over as Romanenko passed him, and managed to grab the line. In so doing, he saved the other man’s life. Had Romanenko passed a few more feet from where Grechko was working, he would have floated out and away, free until his air ran out and he suffocated.

Once both men were inside the air lock, they debated whether or not to tell Moscow Mission Control about the incident, and decided not to. In fact, the cosmonauts didn’t tell anyone about it for months, even after their return to earth. Grechko eventually broke the news at the post-flight news conference. At the end of a prepared statement, he volunteered to comment on “some details which we did not report to earth,” as he delicately termed it.

“I hope that the flight directors will not be offended,” Grechko said carefully, “but we concealed the fact that it wasn’t just me who went out into open space, as was called for in the program, but also commander Yuriy Romanenko. It was very difficult, naturally, for him to restrain himself. It turned out that he had forgotten to fasten his safety line, and I had to grab hold of his line and hold on to him.”

The Soviet space officials may have been unhappy about this (and the story was kept out of most of the newspapers), but the cosmonauts were apparently not reprimanded and both made additional space missions. In later years, a miffed Romanenko told me that Grechko had exaggerated his role in catching hold of him as he was drifting by. But Grechko stuck by his story, and he has always been a heroic story-teller.