FLUG REVUE July 2003: ISS needs emergency plan

ISS NEEDS EMERGENCY PLAN

By Matthias Gründer

The impact of the Columbia catastrophe on the manned space programme of the international community is enormous. Yet while the investigations are still under way, the ISS partners are already taking measures to preserve the station.

Russia is to launch an extra Progress cargo supply craft on top of the Soyuz capsules and Progress transports already scheduled for this year. Seven flights carrying crew and cargo are then planned for 2004. Russia's President Vladimir Putin and US President George Bush have agreed to increase the number and necessary financing for the ISS “lifeboats”, with the Russians bearing the lion's share as Congress has blocked an extra infusion of funding by the USA because of Russia's continuing military aid to Iran.

Space Station

Yet the need to shell out unexpected extra millions on the spaceships and their launch vehicles is not the only nasty shock. At present there are twelve Progress craft in various stages of construction at Energia's Moscow plant, whereas what is needed, in an accelerated timescale, is a large number of finished vehicles. But these normally take about two years to build and test thoroughly.

The rate of production and delivery must now be stepped up without any compromising of safety, as a mishap would mean the end of the Russian involvement for a long time. This in turn would mean the end of the ISS. As NASA administrator Sean O'Keefe points out, “Just one failure and the crew will be ordered to turn out the lights and come home.”

If this worst possible scenario were to occur, it would still always be possible to continue to control the station from the mission control centres in Moscow and Houston in an unmanned regime. The Russians in particular have experience at this kind of operation, thanks to their Mir space station. Even if the ISS could no longer be maintained due to the failure of several components, a rescue mission could be launched. Once again, the Russian cosmonauts are practised in this area. And if the worst came to the worst, it could always be destroyed safely using technology that is currently available. Every effort is now being made to avoid this horror scenario for space science.

Nevertheless, at present the Russian missions offer the only possibility of keeping the station going. Fuel and supply goods are available in sufficient quantities. Above all, the fuel reserves on the Progress cargo ships are sufficient to enable the ISS to be periodically reboosted so as to maintain its proper altitude. Even if in the past this job was frequently undertaken by the shuttles, no changes are called for in this regime.

On the other hand, keeping the ISS supplied with drinking water is a more serious problem, since this was normally supplied by the shuttle orbiters. The water was created as a “waste product” of the fuel cells used for the onboard supply of energy. Meanwhile the Progress transporters can only deliver relatively small quantities of water, so that the shortfall will now have to be made up through the Soyuz flights. This in turn means that for capacity reasons they will only be able to carry two astronauts.

But with only two men, station operations will be reduced to monitoring and maintenance work, and scientific experiments will have to be cut back to the minimum. Another effect of the reduction in the number of crew who can be carried is that this year alone the Russians will lose out on some $45 million of revenue they were expecting to be paid for transporting guest cosmonauts, which was firmly built into the budget.

All in all, station operations can be maintained in this way for at least a year without shuttle supply flights. If by October, when the next shuttle mission STS-114 is scheduled to lift off, the space shuttle is still not available, the present resident crew no. 7, Yuri Malenchenko and Edward Lu, will be relieved by expedition crew 8, consisting of Michael Foale and Alexander Kaleri, who will be transported by Soyuz capsule. Foale, a veteran of the Shuttle-Mir-Missions, was to have been the commander of the eighth crew in any case, but Kaleri was actually the third man in the seventh resident crew. He too is a highly experienced astronaut.

The European Space Agency is also affected by the change of plan, as its astronauts Pedro Duque and André Kuipers will fly six months later than was planned. Despite this, ESA has already transferred the money for the two men's “flight tickets” to Russia to ease the Russians' financial situation.

Now that the Russian parliament has agreed to make new funds available for the station, Russia's contribution next year will climb from the $130 million that was originally planned to $240 million. Without these funds, the station would have had to be mothballed, warned Yuri Koptiev, Director General of Rosaviacosmos, the Russian Space Agency.

All these changes mean that the Russian launch calendar for ISS-bound missions is now very busy. This year, there will be five spaceship launches, followed by a further seven next year. Soyuz TMA-2 has already taken off with the seventh resident crew on board. On 8 June, Progress tanker M1-10 will lift off, to be followed in August by Progress transporter M-48 . Soyuz TMA-3, carrying the eighth resident crew, is to be launched on 18 October, while Progress M1-11, setting off on 20 November, will safeguard supplies.

Progress M-49 is scheduled for January 2004. Then on 20 April Soyuz TMA-4 will be launched with the ninth expedition crew plus André Kuipers of the Netherlands. The launch dates for Progress transporters M-50 and M-51 are to be fixed between January and July, while that for Progress M-52 is already scheduled for August. The tenth resident crew will fly to the ISS in November, to be followed finally by Progress M-53 in December.

All these missions will keep the ISS going, irrespective of whether shuttle flights resume as planned from the spring of 2004. Meanwhile, NASA's investigation into the catastrophe is getting closer and closer to the cause. If its findings can be verified and the necessary design changes are undertaken, STS-114 could then be launched under Commander Eileen Collins and the main burden of supplying the station would shift back towards the reduced shuttle fleet. Without the shuttles the life of the ISS hangs by a thread and further expansion is simply not possible, as all the assembly work relies on the aid of the shuttle manipulator arm and working spacewalks.

Only the Russians have the technology needed to automatically couple such components, but no one is prepared to undertake the necessary upgrade work – and to pay for it. The same old story. In this emergency situation, the international community will never forget whom they have to thank for the survival of the ISS.

From FLUG REVUE 7/2003

Last updated 11 June 2003

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