NASA has released a new 45-flight assembly schedule for the International Space Station (ISS) under which permanent manned operations of the station are due to start in January 1999 and reach completion in 2003 - nine years later than planned when the programme was inaugurated by US President Ronald Reagan in 1984.
The Russian functional control module, called the FGB - providing propulsion and power - will be the first ISS element to be launched, aboard a Proton booster in June 1998. This will be followed by the Space Shuttle STS88 Endeavour mission in July, to attach the Node 1 and pressurised mating adaptors.
The much-delayed Russian Service Module - which will also serve as the first living quarters - is now scheduled to be launched in December 1998.
NASA will continue with the development of an Interim Control Module in case the Russian Service Module is not delivered in time. This will add $200 million to its costs (Flight International, 23-29 April).
The delay to the delivery of the Service Module caused the ISS schedule to be pushed back by at least eight months. If Russia continues to cause production delays as a result of lack of money, it could still be ousted from the project.
The Russian Space Agency has still to receive the full $139 million required from the national government. Another $170 million is due to be released to the agency within three months.
During the construction phase, Russia is supposed to be investing an estimated $3.2 billion in the ISS, compared with NASA's $17 billion, not including Shuttle launches.
The Service Module launch will be followed by two more STS missions carrying equipment, truss adaptors, a Ku-band antenna and gyros, to allow the ISS to be able to accommodate the first permanent crew to be launched aboard a Russian Soyuz TM spacecraft, in January 1999.
The crew will consist of ISS commander Bill Shepherd - who will act as the Soyuz TM researcher - Soyuz commander Yuri Gidzenko and flight engineer Sergei Krikalev. The choice of Shepherd as ISS commander rankles in Russia. The original Soyuz commander, Anatoli Solovyov, resigned his post in protest.
The US Laboratory Module will be launched in May 1999 and the integration of the Canadian remote-manipulator system will begin in June 1999.
While the Japanese Experiment Module will be delivered in August 2001, Europe's Columbus Orbital Facility (COF) may not arrive at the ISS until 2003, as there are 13 missions scheduled after June 2002, of which that of the COF is the last on the list. Outfitting of the US Habitation Module will not be completed until December 2002.
The schedule includes 33 Shuttle missions and 12 Russian launches, not including Russian unmanned Progress supply tanker missions, of which there will be over 15 within 18 months, a much greater launch rate than has been achieved so far in missions to support the Russian Mir space station.
There will also be Soyuz TM launches carrying crews to the station. Two Soyuz TM craft will remain attached to the ISS as rescue vehicles in case an emergency evacuation is required. Another crew emergency-return vehicle may be developed later.
The completed ISS will consist of 36 units weighing over 400t, with a pressurised volume of 1,100m3 (35,300ft3). It will eventually have an operational crew of six. The total cost to NASA by 2012 will be about $100 billion.
Source: Flight International
