28 February 2003
"A patchwork plan for space rescue"
'What-if' scenario might have employed payloads and second shuttle for survival

By James Oberg,

An Ariane 4 rocket lifts off on Feb. 15 from the European Space Agency's launch center in French Guiana. Could this rocket have carried up supplies as part of a Columbia rescue plan?

HOUSTON, Feb. 28 - The dramatic video from the flight deck of the space shuttle Columbia, shot just minutes before it was destroyed, has sparked new interest in a nagging question: What could NASA have dreamed up to save the astronauts?

THE "WHAT-IFS" all assume an early realization that the shuttle's thermal protection system - its tiles - had been mortally wounded. Perhaps, if program managers had been alarmed enough by the debris impacts noted after Columbia's launch on Jan. 16, they would have wanted more information before deciding it was no big deal. In that case, again "perhaps," the damage could have been seen by military telescopes or spy satellites, or by a daring free-floating spacewalk.

But then what? If a landing looks suicidal, and refuge at the international space station is out of reach because of incompatible orbits, how can the crew be rescued before there limited stock of supplies runs out?

Just after the tragedy on Feb. 1, shuttle program manager Ron Dittemore said "there's nothing that we can do about tile damage once we get to orbit." NASA has not yet figured out a way to perform repairs on damaged or missing tiles in space.

But that doesn't mean the situation would have been hopeless, NASA Administrator Sean O'Keefe insisted Friday.

"To suggest that we would have done nothing is fallacious," O'Keefe said in a meeting with reporters. "If there had been a clear indication (of  problems) there would have been no end to the efforts."

CRUEL CALCULUS -- In all the post-catastrophe speculations about possible rescue missions, there always remained an unbridgeable chasm between how long the crew members could stretch their life support systems, and how long it would take to get a rescue shuttle mission to reach them. The cruelcalculus of this spaceflight crisis came to an unhappy conclusion: The astronauts would die, probably of carbon dioxide poisoning, before a rescue mission involving a second shuttle could be mounted.

But this is not necessarily inevitable, it turns out. Amateurs and retired space workers have been able to develop at least one miracle maneuver to bridge that gap. Given a few days and the full-powered brainstorms from Mission Control and throughout the space industry, the rescue plan - or ideas even better - could almost certainly have quickly been made workable.

This gimmick would be to launch an emergency supply payload into orbit within a week of the realization of the crisis, aboard an expendable launch vehicle. Several such packages would be prepared in parallel, because mission success of any one of them might have been 50-50 or even less. But with enough attempts, one of them would likely have worked.

The package would weigh at least half a ton, maybe a lot more, and would contain all the materials needed to extend the crew's survival for several more weeks. Most critically, it would carry the air-scrubbing chemical packs to keep exhaled carbon dioxide below harmful levels. There would be food and water, waste management bags, batteries, and blankets - it would get cold really fast on this orbital campout. There would be medications, including drugs to reduce the astronauts' metabolism rates as low as possible to conserve air.

But the most precious cargo aboard such a payload would be hope, both for the stranded crew and for their loved ones and colleagues and everyone else back on Earth.

DELIVERY SYSTEM -- What kinds of rockets were available for sudden redirection? And how readily could they be reprogrammed?

First, we know which rockets were not available. No Russian rockets could have helped, because Russia's launch sites are too far north to allow launchings into the more southerly orbit followed by Columbia.

But many others were available. At the European launch site at Kourou in French Guyana, a powerful Ariane 4 booster actually was in its final days of countdown. Other expendable boosters were in various preparatory stages in India, China and Japan, and of course at U.S. launch sites, both government and commercial. Lastly, among the Pentagon's fleet of MX Peacekeeper and Trident military missiles are some already tagged with combat orbital missions, and they too could carry a ton or more of lifesaving equipment into orbit.

The resupply payload's orbit would have to be compatible with the stranded astronauts. It would need to be at the correct orbital inclination to within a tenth of a degree, and it would have to blast off to within a second or less of the exact launch window that allowed compatible flight. Computers could be reprogrammed for these paths within a few days, but the risk of human error would be considerable. That's why many attempts would have to be initiated.

Once any one of these packages reached a compatible orbit, Columbia could do the rest. Since its propulsion system was still functional, it could have chased down the package and performed a space rendezvous with it.

This is a standard maneuver that all astronauts receive summary training for, although it was not part of the original STS-107 mission. So in the days while the rescue rockets were being prepared, Houston could fax up a set of reference books and charts to be used by the crew. They would even have time for several dry-run practice sessions. Exactly such an unplanned rendezvous - although only to save a payload, not the crew - was performed by an untrained shuttle crew in 1985, and it worked perfectly.

Once the shuttle had approached the supply package and had it floating over its payload bay, the next tricky part would begin. The two spacewalk-trained astronauts would be outside ready to grab it by hand - and for that reason, lots of handholds would have been bolted all over it. They then would snap their safety lines onto pre-installed attachment points, and tie the package down.

For however many cycles it took, they would load up the shuttle's airlock with hand-carried packages, close the outer hatch, and let their companions inside unload the goodies. Then they too would come back inside.

STRETCHING LIFE SUPPORT -- The next stage - stretching their lives while ground teams prepared the rescue shuttle - would be equally challenging. The shuttle would be configured for "slumber," with many systems (such as the aft-end thrusters) turned off forever to save power. Perhaps the fuel cells, one after the other, could idle at minimum for an extended period, or perhaps they too would eventually have to be turned off. Navigation and even communications gear would be shut down. Heaters would be off, and the cabin would drop to near freezing.

But with their rescue kit, the air would stay breathable. With their blankets and warm clothing, the crew would remain comfortable. With their portable emergency radio, they could get in touch several times a day. They would spend as much time as possible sleeping, or sedated. What they would be thinking as the days stretched to weeks would be unknown to Earth.

Columbia would have been visible from Earth at dawn and dusk as a bright, fast-moving star. Human eyes all over the world would have been raised to the heavens at a level not seen in a generation or more.

Assuming in the end that a new shuttle was ready, and that the accident that caused the mortal wound to Columbia could be prevented from happening again, the day would finally come when a rescue mission blasted off. Its crew would have been reduced to four, perhaps, but that would be enough to perform all required maneuvers.

After reaching the drifting Columbia, the rescuers could tie a line between them and set up a "gravity gradient" stationkeeping posture - a maneuver tested as far back as the Gemini program in 1966. Spacewalkers could go across with emergency suits (perhaps even the dusted-off "rescue balls" designed back in the late 1970s) and begin evacuating the stranded crew. Each of those activities would be composed of routine steps from scores of earlier shuttle missions, but strung together in a most non-routine pattern.

Seating for landing would be no problem. Astronauts could just deploy a mat on the floor of the middeck and tie the now-rescued astronauts down prone. They would ride back to Earth safely in that posture.

None of these steps is individually impossible, and in fact most have been performed piecemeal in the past. Everything needed to do it this way - or in any of a dozen better ways that the space teams could have devised - was already on hand.

The key missing ingredient was not ingenuity and determination; it was insight into the seriousness of the original damage. The requisite "situational awareness" wasn't there when it should have been. And that, in reality, is the actual missing link that prevented saving the crew.

New gadgets and gimmicks are sexy, and NASA will indeed build them. But it is only in finding out how that mental awareness went wrong that they will discover the key to minimizing - but never eliminating - the chance of such accidents happening again.

James Oberg, space analyst for NBC News, spent 22 years at the Johnson Space Center as a Mission Control operator and an orbital designer.


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