After Columbia: The ISS in Crisis

Can a space station suddenly put into survival mode by the shuttle disaster survive orbital challenges and earthbound critics?

by NASA

The ISS seen from the shuttle endeavour in June 2002, 7 months before construction is halted.

It was a terrible accident, at a terrible time. When the Space Shuttle
Columbia disintegrated 200,000 feet above Texas on the morning of February 1, seventeen years after Challenger, several things happened. Americans woke to another televised lesson in the dangers of an adventure that, surely, we had not really forgotten is perilous. We received a crash course in the complexity of the space program and of the shuttle system in particular — the tiles, the heat, the speed, the data, the dollars (and, critics said, even in the early hours, the folly). Within hours we were reading seven suddenly heartbreaking biographies that gave fresh insight into the competence, coolness and clarity of purpose that seem to be in the DNA of all astronauts, whether they arrive from the pilot side or the science side. And we were made to consider, at the margins of the first day’s unfolding drama, the plight of the International Space Station.

That’s where the terrible timing comes in: ISS. Before the Columbia tragedy, 2003 was to be a make-or-break year for the troubled space station. Starting
in March, the first of seven critical shuttle launches to the ISS would get under way. Those seven launches would support an exciting building spree as NASA and its partners raced toward a 2004 completion date for the first phase of the station.

Shortly before the Columbia disaster, NASA Administrator Sean O’Keefe told Popular Science that February 19, 2004, was a date “emblazoned in the mind” of everyone involved with the program. It was clear that NASA relished the hard engineering challenges ahead, following more than a year of intense budget controversy and political sniping. With what now seems like ominous understatement, O’Keefe added: “I don’t think there’s anyone in the agency who is looking at this as a slam dunk.”

February 19, 2004? Alas, the date now emblazoned on everyone’s mind is February 1, 2003.

The Crew Gets the News

Two Americans and a Russian were onboard the ISS when Columbia re-entered the atmosphere. They learned about the accident an hour after it happened. “They feel a little isolated,” said Flight Crew Operations chief Bob Cabana.

In those first hours post-disaster, while most of NASA’s energy was focused on data and debris recovery, ISS managers took stock. An unmanned Russian Progress cargo ship was scheduled to be undocked from the station that day. The one-time-use Progress ships routinely supply and service the station. They generally take about two tons of freight to the ISS, then serve as a dumpster before being directed back to Earth’s atmosphere, to burn up on re-entry. This Progress had to go because another was to be launched February 2. But with the shuttles now grounded, ISS managers had to pay close attention to the cargo load of the next Russian craft.

“We started working immediately with the Russians,” said station program manager Bill Gerstenmaier the day after the disaster. “We ensured that the undocking didn’t have any adverse impact on what we were going to do with the station, in light of the fact that the shuttle may not be there for a while. [Then] we went on to the next Progress and looked at its manifest, went through a very rigorous assessment to ensure that it was the right cargo.”

The Progress launch on February 2 went smoothly, and the craft docked with the ISS two days later.

The loss of one shuttle and the grounding of the remaining three instantly severed the ISS’s heavy-cargo supply chain for an indeterminate time. Only a thin lifeline remained, courtesy of the Progress freighters and the small, manned Russian Soyuz capsules. (If the shuttles are the monstrously expensive 18-wheelers of the program, the Progress ships are the light trucks, and the Soyuz the taxicabs/lifeboats.) ISS construction plans ceased immediately, and NASA, the lead partner in the 16-nation ISS program, said it would focus on maintaining a caretaker crew of three. Among the near-term and looming challenges: optimizing energy use, keeping the ISS intact until replacement parts can again be delivered, and dealing with the station’s perpetually decaying orbit. “It will be in survival mode, not development,” Vyacheslav Mikhailichenko,
a spokesman for the Russian space agency, Rosaviakosmos, said two days after Columbia.

In the days after the shuttle’s break-up, the ISS crew was in no greater immediate peril than it was pre-Columbia, because there is always a Soyuz capsule attached, for use as a lifeboat in emergencies. NASA announced that the ISS had adequate food supplies until June. With no shuttles available for crew swaps, the current crew — or “expedition,” as each crew cycle is called — will likely extend its stay, which presents no special challenges. (At press time, NASA was reported to be considering a crew swap using a Soyuz capsule in April or early May.) “Through the short term, through this summer,” said Michael Kostelnik, a senior NASA space flight administrator, “everything is fine. The crew is healthy, motivated and willing to stay. We have the supply-and-support with Progress laid in. We always have the lifeboat.”

But survival mode will involve canny planning and hard choices by NASA as the year wears on. The big problem is the station’s altitude, and the energy required to boost the ISS higher. Having grown to 197 tons, with living and working space equivalent to that of a 3-bedroom house, the ISS slips slowly toward Earth by 500 to 650 feet a day. Drag from the small amount of air 250 miles up gradually slows the station. This orbital decay has been compensated for with regular rocket firings from docked vehicles such as shuttles and Progress ships. But without the big shuttles, there probably isn’t enough fuel in the tanks of the scheduled Progress missions (two more this year) to maintain the desired altitude over the long haul. And there aren’t any new Progresses available, even if NASA wanted to speed up the Russian launch schedule.

It’s not as if the ISS will fall out of the sky tomorrow. (In February, NASA officials talked about the altitude problem being in hand for the calendar year.) But without a significant increase in reboost capability, by early 2004 it will have slipped to levels where air drag increases alarmingly. To slow this decay, ISS managers must make some choices. They could choose to “feather” the solar arrays to reduce drag, but this saps the power supply because the panels won’t always fully face the sun. They could also eliminate a safety measure, in which discarded Progress freighters are powered away from the ISS, and instead use the fuel needed for that maneuver to boost the station.

Meanwhile, the ISS will, like any expensive piece of machinery in extreme conditions, suffer wear and tear. Along with big construction modules, the shuttles also hauled spare parts. Progress can transport some of these items, but large, important replacement components will not be arriving anytime soon. Among the 2003 shuttle missions was to be the replacement of a solar-powered Control Moment Gyro (CMG) for the American attitude control system. (By varying the motor speed of these heavy spinning disks, the station can torque itself into new orientations or hold itself against external disturbances.) Originally, there were three active CMGs and one backup, but one broke, and one of the others is experiencing sporadic hiccups. With only two CMGs working, significant amounts of propellant will be needed to steer the ISS.

Among the options NASA will likely consider to boost freight capacity: Accelerate the launch schedule for a European vehicle, dust off a stalled Russian program, and fund an increase in the manufacture of Russian Progress ships and Soyuz capsules. The European Space Agency is scheduled to launch a robotic Automated Transfer Vehicle in September 2004, with about three times the two-ton freight capacity of Progress (the shuttle carried 20 tons). The manager of that program, Robert Lain, says, “The possibility to gain a few months in the launching of the first ATV is likely to be studied by ESA if it is of interest to our NASA partner.” Meanwhile, a Russian-built backup ISS module called FGB-2, more than 60 percent completed before work halted in 2000, might be rushed into service, though that could take a year or more. As for Soyuz and Progress craft, the Russians sound like they’re eager for the orders (see “Can Russia save the day?”), but it’s not like adding a shift to the assembly line at a Peterbilt factory. Short of a rapid shuttle relaunch, there’s no quick fix to the ISS supply problem.

Billions and Billions and Billions

When he spoke at the memorial for the Columbia crew, President George W. Bush affirmed the importance of the space program to the nation, though he did not mention the ISS by name. In the aftermath of Columbia, space program supporters were quick to offer reassuring words. “Whatever happens, we are not going to give up our investment in the International Space Station,” said Senator Bill Nelson, a Florida Democrat who flew on Columbia in 1986. “You have folks in Congress who are going to make sure we don’t lose our space program.”

A fine sentiment, but there are folks in Congress, and outside it, who will find in the disaster ammunition for renewed attacks on the station. To critics, the shuttle and ISS have long been like Siamese twins on grossly expensive life support, sucking resources ($6 billion of NASA’s $15 billion budget for 2003) away from what they say the space program should be doing. ISS was supposed to be finished by 2003 at a cost to the U.S. of $17.4 billion. Delay boosted the price, and the U.S. cost to get to U.S. Core Complete stage alone will be $24 billion to $30 billion. Total U.S. costs — planning, construction, shuttle missions, and 10 years of ISS operation — will be much higher, and have ranged north of $95 billion, an astonishing figure found in a 1998 General Accounting Office report. ISS and shuttle detractors may call for an expanded program of robotic exploration, a drive to develop safer, cheaper, next-generation, single-stage-to-orbit vehicles, or a speed-up of research to develop the propulsion systems needed to get a ship and crew to Mars.

Shortly after the disaster, space historian William E. Burrows decried the dangerous “Roman candle” shuttle technology, saying that the “bilge” in the space program has yet to be purged. He neatly sums up the skeptics’ viewpoint: “The ISS has no real function except to be there, and that’s very sad.”

Which brings us back to those seven now-grounded shuttle missions to the ISS scheduled for 2003 and 2004. Those missions were designed to get the station to a phase called U.S. Core Complete, when Node 2, a critical U.S.-built expansion module, would be attached. This would bring the ISS to minimal station functionality (think of your basic cable TV package, without any added goodies), and Congress, which has been critical of ISS budget management, could decide to block new funding or additions to the station while arguing that it had met its minimum obligations to international partners. That would leave the ISS, however, with room for only three permanent residents, basically hobbling its capacity to do much science — and science was the reason for building the station in the first place.

In the wake of the Columbia disaster, reaching U.S. Core Complete may be delayed by at least the amount of time
it takes to get the shuttle flying again. Even if the European or Russian space program accelerates its freighter program, some components were designed specifically for the shuttle’s cargo bay. Another likely cause of delay: A relaunched shuttle program will be less efficient simply because there will be fewer of the high-maintenance, long-turnaround spacecraft in operation. If the delay is, say, two years (Challenger grounded the fleet for 33 months), then it could be 2006 before U.S.
Core Complete is achieved, and 2008 to 2010 before critical European and Japanese laboratories are added. By then the space station’s original planned on-orbit lifetime will be more than half over.

A 2002 task force
called ReMAP, appointed by NASA, warned that if NASA doesn’t take the ISS beyond U.S. Core Complete, it should “cease to characterize the ISS as a science-driven program.” The fundamental question about the post-Columbia ISS is: Can NASA and its partners reasonably expect to get the station beyond basic-cable stage? Or should NASA cut its losses and focus on launch-
system initiatives and other challenges? We know what happens at NASA when there are budget constraints and hardware problems: ISS science is whacked. Facing a hefty $4 billion to $5 billion ISS budget overrun in recent years, NASA repeatedly opted to squeeze, chop and delay research programs. The ReMAP report noted that research funds had been diverted four times to cover engineering overruns, and “total research slippage” had been four to five years. Scientists were furious when long-planned experiments were “deselected.” Some walked away from further ISS involvement.

Some of this rancor seemed to be moving toward repair shortly before Columbia. O’Keefe had emphasized the importance of science, promised more science-focused shuttle missions, offered assurances that the final ISS crew count would be greater than three, and affirmed that NASA would increase the budget for experiment facilities while tweaking ISS crew schedules to allow more research. Some in the scientific community seemed reassured. “They’re trying to improve relations,” Stephen Doty, outgoing president of the American Society for Gravitational and Space Biology, said pre-Columbia. “I’m hoping this is a turn in the right direction.”

Time to Light a New Candle

The fate of the ISS comes back to the shuttle, or its successor. Even though the space shuttle was supposed to fly for another 20 years — meaning refurbished shuttles that were some four decades old would be launching in 2020 — NASA knew it
needed a replacement system. Programs to develop one date back to the Challenger accident but were repeatedly scrapped, either for budgetary reasons or because the technology was unproven. As recently as November 2002, the agency had cut most of the money from its 21-month-old Space Launch Initiative (SLI) project for a new reusable rocket. By January, the agency was left with a modest plan to build an Orbital Space Plane (OSP) that would be launched by a heavy expendable rocket. Rather like a crew-cab pickup truck, the OSP would deliver crews and some supplies to the ISS and also act as a rescue vehicle. Before Columbia, NASA said it would launch the OSP by 2010; that schedule may now be accelerated. But OSP does not account for the shuttle’s heavy-cargo role, and would have to operate in conjunction with the shuttle until a newer system came along.

Paul Czysz, a professor at St. Louis University and a former senior engineer at McDonnell Douglas, is an expert on space planes and has recently been part of a team advising NASA on future launch plans. Czysz warns that NASA should stop dreaming about distant technologies and ask: “What can we do right now that we already know how to do? We need a space transportation system more than we need a space station.”

Space program supporters can consider one heartening fact: Whatever the merits of, or prospects for, science aboard the ISS, the station is an extraordinary engineering feat accomplished through remarkable international cooperation. In its time of need NASA may find inspiration not by looking to the stars but to the people who kept the patched-up Mir
station flying against long odds and without much money.

“I think,” says Victor Nikolaev of Starsem, a joint Russian-European company that provides launch services for Soyuz, “that now in Russia we all understand that we make together — with our partners — the history of space conquest. We are tied to each other for the calamities and for the successes.”

Reported by Irene Brown in Florida, James Oberg in Texas,
Frederic Castel in Paris, Bill Sweetman in Minnesota and Greg Mone in New York City.