In-orbit assembly of the International Space Station is to start this autumn

Tim Furniss/LONDON

Launch of the first components of the International Space Station (ISS) is due to start on 20 November, but sceptical observers are not holding their breath.

The Russian element, which saved the ISS from the US budget axe four years ago, has created very public problems for NASA, mainly caused by the country's cash shortages. The US space agency, however, has had its own difficulties - this time not budgetary. Technical problems have delayed components and the US Laboratory Module, due for launch in October 1999, is not yet out of the woods.

NASA and its international partners have amended the ISS assembly plan, which will involve 43 flights, aiming for completion in January 2004 with attachment of the US Habitation Module. Launches will mainly be by US Space Shuttle, but Russia's Proton and Soyuz will be used to boost components into orbit.

NASA is keeping its options open on possible further delays to the Russian Service Module, which it is hoped will be launched in April 1999. The agency is continuing with development of a back-up US Interim Control Module as an alternative.

Russia also plans to keep its Mir 1 space station operational, in case the ISS is delayed - and in case it gets dropped from the project, or reduced to a minor partner. Russia is resisting proposals by NASA to de-orbit the Mir in July 1999, and wants to keep the ageing station going until 2000, as it generates income from guest cosmonauts.

Crews have been chosen for the first flights to assemble the ISS during several spacewalks, and then to inhabit the Space Station. Command of the three-person crews to work shifts on the ISS will alternate between US and Russian personnel. NASA astronaut Bill Shepherd will be the first ISS commander, flying as a research engineer on a Soyuz TM, while the first Russian commander will be Yuri Usachev, who will fly with his crew on a Shuttle assembly flight.

The first international partner, other than the USA or Russia, to get a major ISS component into space will be Canada, with its robotic Space Station Remote Manipulating System, due to be orbited in December 1999. The first of several Italian Multi-Purpose Laboratory Modules will also fly on that mission. The Japanese Experiment Module logistics module will be added in October 2001, followed by more Japanese equipment. Europe, often seen as the poor relation, has seen the launch of its Columbus Orbital Facility pushed back to February 2003.

The pressure is on NASA because so much of the success of the ISS is dependent on the Space Shuttle.

A major problem with an Orbiter would leave the space agency with little leeway, since only three of its four Orbiters, the Atlantis, Discovery and the Endeavour, are capable of flying ISS missions. o

Source: Flight International