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Popular Science
December 1999
pp. 116-123

Are The Russians Lost In Space?

By James Oberg

 

Sometime in the next few months, the third and arguably the most critical element of the International Space Station was scheduled to be launched aboard a Russian Proton rocket from the Baikonur cosmodrome in Kazakhstan. Designed and built in Russia, and modeled after the core module of the Mir space station, Zvezda ("star" in Russian) will serve as the crew living quarters over the next four years while the station is being assembled.

But will Zvezda, which until recently was known as the Russian Service Module, actually be in orbit by the time you read this? The module was originally scheduled to be launched in early 1998 but has been repeatedly delayed, pushing back the entire assembly sequence. And even if this first major Russian-funded component of the station does go up as planned, other promised Russian contributions may never be delivered, due to lack of funds.

When Russia was brought aboard the International Space Station project in 1993, NASA promised the partnership would save billions of dollars and several years of construction. More important, the station offered a diplomatic opening to the post-Soviet Russian government, without which President Clinton may have cancelled the entire project, already hopelessly over budget.

Although NASAÕs rosy forecasts were way off target Ñ the Russian presence has contributed to vast cost overruns and schedule slips Ñ things could get even worse. If the Russians drop out of the program now, or are expelled, replacing them will take at least three years and much, much more money. Those costs might threaten the project with cancellation again.

But unbeknownst to most people, NASA does have a draft backup plan for building the station without the Russians. Over the last few years, the agency has quietly developed several spacecraft of its own that can serve as understudies for promised Russian elements. And before Zvezda is launched, Congress expects NASA to finalize its contingency plan for completing the station without Russia.

That wonÕt be easy. The Russians are in what's known in space jargon as "the critical path." The other 15 nations participating in the project are relying on Russia not only for crew life support, but also for such key components as the crewÕs emergency escape system, rockets that keep the station in the proper orbit, and some of the solar panels that provide power. With the Russian equipment, the station's capability is impressive. Without it, the project is in deep trouble.

Just consider the dilemma of the Interim Control Module, or ICM, a 10-ton conglomeration of computers, rocket engines, and propellant tanks. Faced with the possibility of excessive delay of some Russian components, in 1997 NASA finally decided to purchase this spacecraft, a modification to a design already used in a military program managed by the Naval Research Laboratory (NRL).

But if you look at NASA's official "Assembly Sequence" for the station, you wonÕt see the ICM anywhere. That's because NASA still doesn't know which potentially missing Russian spacecraft the ICM will be used as a substitute for. And depending on where and when it is to be used, engineers have to install different latching equipment and computer software.

If it stands in for a delayed or cancelled Zvezda, the ICM would hook to the Zarya module already in orbit. But if Zvezda is delivered, and the Russians subsequently renege on a promised refueling flight, then the ICM would be loaded with fuel and attached to another module, using an entirely different type of docking mechanism.

The ICM is cheap by space standards, because it is being assembled mainly from "residuals," hardware that had been in storage. "We already had a structure, the rocket engines, the tanks, and a lot of electronics," program director Al Jacobi explains. These components had originally been designed for a top-secret Pentagon payload that would have ridden into space aboard the shuttle Challenger in the late 1980s. But after Challenger exploded, most military payloads were diverted to expendable boosters, and the vehicle hardware was stashed away.

Still, the module required "sizable modifications," according to Jacobi. To begin with, the original vehicle was a "spinner": It slowly rotated around its long axis as it drifted through space. For the space station, the module had to be stabilized.

Slow spinning is desirable for space flight, Jacobi says. It evens out the vehicle's temperature, and it causes the propellant in the tanks to settle into a predictable location. Without spin, significant design changes were needed. Engineers had to add a new thermal control system, including a heat pipe and thermal radiators to dump excess heat generated by sunlight and onboard electronics -- doubly important, since NASA required the redesigned module to carry twice as many computers as the original.

NRL engineers also had to add special ducting to the inside of the propellant tanks, to feed liquid into fuel lines. "That was a challenge," Jacobi recalls, because the tanks are 52 inches in diameter and were built with only 5-inch-diameter inspection ports. The mesh ducting, similar to a system used inside the shuttleÕs propellant tanks, had to be built in sections small enough to fit through the holes. "It was like building a ship in a bottle," Jacobi says.

The ICM, which will not be ready for flight until late next year, is only the first of several expensive alternatives that NASA has had to develop to accommodate delays and cancellations of promised Russian contributions to the space station. According to NASA, the Russians provide the station with critical services in eight specific functions: guidance, altitude control, life support, communications, power, spacewalk support, emergency crew return, and ground support.

As a power provider, for example, the Russians originally promised to supply a module called the Science Power Platform (SPP), which would have large solar panels and gyroscopes for turning the station in different directions. The SPP would be launched piecemeal aboard three Russian Zenit boosters and would automatically dock to the station.

The Russians soon realized that the SPP would be too heavy for their own rockets. As part of an even-handed deal in which the Russians promised to develop a new robotic supply vehicle, NASA agreed to carry the SPP into space aboard two shuttle flights. Cost to U.S. taxpayers: $1 billion. The Russians later told NASA they wouldn't be able to build the supply vehicle, but they kept the two shuttle flights Ñ in fact, NASA added two more flights to carry additional space hardware the Russians discovered they couldn't afford to launch on their own.

The SPP deal continued to sour. It turned out the Russians couldn't afford to build the SPP at all, even though NASA's station design depended on the promised electrical power, heat-dumping radiators, and steering gyroscopes. So now NASA is considering an additional U.S.-built photovoltaic power module, and may have to fly the entire space station pointed in a different direction to maximize solar power production.

When the United States and Russia first agreed to build a station together, the downside of cooperation seemed slight. True, in order to launch space shuttles into a more northerly orbit (so the Russians could reach it) meant that NASA would have to accept a 25 percent payload performance penalty on each half-billion-dollar shuttle flight to the station.

But unforeseen problems soon surface. Within a year of agreeing to collaborate on the station, the Russians began delaying some items and backing out entirely from others. Year by year, the list of promises has shrunk and the costs have expanded. By last year, all the news from Russia was glum. Promised funding had totally dried up.

In October 1998, NASA reported to Congress how it planned to handle the threatened loss of key Russian elements. NASA's "Step 1," costing $250 million, had already been approved in mid-1997. That was when NASA at last realized that Russia's ambitious schedule for Zvezda was hopelessly optimistic. NASA insisted that the stationÕs first module, Zarya, be modified so that it could be refueled from docked supply ships.

For the engineers actually building the project Ñ the most ambitious international construction effort in history Ñ the schedule and budget setbacks are all water under the bridge. The engineers are faced with a practical and more pressing problem: What can be done now to proceed with the project in the least expensive way?

The question is no longer theoretical, since the first two pieces of the International Space Station are already in orbit. The Russian-built but U.S.-funded Zarya (Russian for "dawn") and the U.S.-built Unity were hooked together on a shuttle mission last December, then left to orbit unoccupied. Their future existence depends on the timely launchings of support missions.

The clock is ticking. Zarya's computers are rated for only an 18-month lifetime, which means that a new vehicle must be docked to it by May 2000 to take over the station's control. If it's not going to be Zvezda, then the ICM must be sent up in its place. But since NASA needs a full year to prepare for a shuttle mission, the decision to send up the ICM should have been made seven months ago.

Even if the ICM could be launched quickly, it is only a short-term and partial stand-in for Zvezda. The ICM does not provide life support Ñ air and water -- for a long-duration crew. Under current plans, NASA wonÕt be launching its own life support system until 2002. NASA has looked at extending the shuttle's capability to stay docked to the station from the current 8 days up to 30 days, but the results were not encouraging.

Even if NASA could speed up the development of a life support module for the crew, how would they get home in the event of an emergency? Currently, the only manned vehicle capable of long-term missions to the station is Russia's three-man Soyuz capsule. NASA originally planned to have one Soyuz launched to the station every six months, to support a three-man permanent crew, as an emergency rescue vehicle. Later, the Soyuz lifetime would be extended to 12 months, so two Soyuzes would always be available, and the station crew could be expanded to six people. The concern now is that Russia may not be able to deliver the Soyuz vehicles it promised.

Since the Soyuz is cramped (among American astronauts, about half can't even fit into its seats) and makes a rough landing (not good for medical emergencies), NASA has long been interested in developing a larger, gentler Crew Return Vehicle (CRV). A special team at NASA's Johnson Space Center is now designing, testing, and building a CRV prototype called X-38, NASA's first new manned space vehicle in a quarter century.

NASA plans to deploy an unmanned X-38 from a shuttle in late 2000, to demonstrate a reentry and landing. If it works, NASA will contract with a manufacture to produce a series of CRVs. But under current schedules, the first CRV wonÕt be docked at the station until early 2003 at the soonest. Until then, if a permanent crew stays aboard ISS, it must have a Russian-provided Soyuz on hand.

NASA may also have to come up with a replacement for RussiaÕs unmanned Progress freighters, which were supposed to provide regular cargo service to ISS and bring up fuel to keep the station from gradually slipping out of orbit and burning up.

Step Two in the contingency plan NASA sent to Congress in October 1998 is to modify the rocket propellant plumbing in space shuttles so as to be able to use extra fuel to reboost the entire station while the shuttle is docked. This will cost $90 million. Although using the shuttle for this function is very inefficient Ñ the thrusting must raise the orbit of both the station and the 100-ton shuttle, then later lower the shuttle by an equivalent amount Ñ it is essentially "free" because it relies on propellant reserves left over from the shuttle flight.

NASA also proposes building a new Propulsion Module, at a cost of $350 million, not including the shuttle flights required to launch and service it. The earliest possible launch date for this module is February 2002.

Without the promised Progress missions, NASA has budgeted additional shuttle logistics flights that will haul cargo up to the station. NASA insists that each supply flight will cost only $100 million, contrary to the widely accepted value of $500 million per launch. Additionally, NASA anticipates the outright purchase of Russian supply missions, but no cost estimate has been given. (Most outside experts put the price of a single Soyuz or Progress launching at about $75 million.) In the long range, NASA plans to encourage the development of European and Japanese unmanned supply vehicles Ñ at no cost to the United States but at a price tag of up to half a billion dollars for its partners.

Under the "official" NASA space station plan, the year 2000 will see 10 Russian launches to support ISS. That's twice the highest launch rate of any year in the past decade and assumes no flights to Mir. NASA has contingency plans for what it calls a "Minimum Russian Support Scenario," which consists of three Progress launches and two Soyuz launches per year (that is, their entire current production capacity). That would reduce station power by 5 kilowatts and reduce propellant supplies by about 2 tons per year, requiring an additional two shuttle flights per year to compensate.

>>Popular Science<< has obtained the presentation charts from an October 1998 NASA briefing on "ISS Contingency Plans," given by Mission Integration Manager Keith Riley. They graphically illustrate the quandary that NASA has put itself in, because even the page titled "No Russian Program Support" assumes that there will be continuing Russian participation.

In this "worst case" scenario, the Russians drop out completely in 1999. However, NASA must still depend on Russia's Mission Control Center in Moscow to operate the Zarya section of the station. To save money, NASA decided years ago not to develop backup command and control capability for Zarya. Somehow, in a situation where Russia has either opted out or been expelled from the project, NASA expects to find a way to persuade the Russians to keep up their control activities for the station until the ICM can be launched.

What if they don't? That merely means the loss of Unity, the one U.S. module attached to Zarya. NASA already had developed contingency plans for the loss of the module during launch, and they could be quickly implemented. There is a spare unit, a "structural test article," which could be made flight-ready in about a year. Station assembly could be resumed by mid-2000,[cut: perhaps in a more southerly orbit that would be more efficient for shuttle operations].

According to Riley's presentation last October, the other two critical replacement items are the Propulsion Module, to be launched no earlier than February 2002, and the Crew Return Vehicle, to be available no earlier than the spring of 2003. Since there would be no way for any long-term crew to evacuate the station prior to the delivery of the CRV, they would never be put onboard, and so there wouldn't be any need to deliver a U.S.-built life support module until about that same time.

In the end, NASA has painted itself into a corner. The agency can handle more delays, and it can handle the loss of Russian logistics support flights. But without the delivery of Zvezda, and without the open-ended availability of semiannual Soyuz launches to keep a bail-out capsule attached to the station, NASA is faced with a three-year delay in leaving a permanent crew aboard the station. Making matters worse, NASA is reported to be behind schedule in readying its U.S. Laboratory module for a scheduled April 2000 launch, and a planned shuttle mission to service the station has been postponed to mid-February because of wiring damage discovered on a shuttle flight last July.

The potential impacts of a prolonged delay in assembling the space station are staggering. They range from lost research opportunities to lost international support, and perhaps even program cancellation. So NASA has realized it must pay any price to keep the Russians onboard the project, through the launch of Zvezda and then for several years of Soyuz launches. And the Russians know it too. The only issue remaining to be decided is how much American money will be transferred to the Russian Space Agency, and what the official invoices will say.

 

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