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The United States can build a space station for $6-$10 billion less than Space Station Freedom, provided NASA and its contractors slash costs, a panel of experts reported Friday.
The report of the Advisory Committee on the Redesign of the Space Station called for "major structural changes in the management and organization of the program within both NASA and the civilian contractors" to eliminate "redundancies and overlapping responsibilities."
To achieve the cost reductions, the Space Station program should have a single prime contractor and "a reduction of at least 30 percent in total civil service and contractor employees assigned to the Space Station Program."
The committee, headed by MIT President Charles M. Vest, was appointed by Vice President Al Gore. It began its intensive deliberations on April 22, seven weeks before delivering its 78-page report to the White House on June 10.
Space station costs, including inflation, to develop the various options fully to "permanent human capability" in the year 2000 or 2001-and to operate the station thereafter for 10 to 15 years-were calculated at:
- ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½Option A, Permanent Human Capability (PHC) in October, 2000-$16.5 billion for development. Subsequent operating cost: $1.4 billion a year.
- Option B, PHC in December, 2001-$19.3 billion for development. Subsequent operating cost: $1.5 billion a year.
- Option C, PHC in January, 2001-$15.1 billion for development. Subsequent operating cost: $1.0 billion a year.
- ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½Space Station Freedom, PHC in March, 2001 -$25.1 billion for development. Subsequent operating cost: $2.4 billion a year.
The NASA redesign team reported that Space Station Freedom-related costs will total $11.1 billion by the end of 1993.
The American experts said Option A, the smaller of the two designs derived from Space Station Freedom, and Option C, the new single-launch design, "are the design options most deserving of further consideration." Limiting Option A to the initial power station phase "is not a worthwhile option for the nation to pursue," they said.
The panel said none of the redesigns fully meets the Administration's desired cost targets or scientific milestones through 1998, although Option A was estimated to reach the initial human-tended capability in July 1998. "All options, however, do represent major cost savings relative to Space Station Freedom."
It added, "The ultimate cost of a space station and its operations will be minimized only if Congress and the Administration make a firm commitment to the program and provide stable funding."
The costs were based on using the planned orbit, 28.8o from the Equator. The panel recommended using the 51.6o orbit used by the Russians because of "safety, flexibility, and redundancy of launch and assured crew return vehicles. [This would] allow access to the station by as many space faring nations as possible". The change in orbit would increase the development costs by $300 million to $400 million for each option.
The Russian Soyuz spacecraft was recommended for the redesigned space station as a new element, the "assured crew return vehicle."
The panel said expendable rockets, such as the Russian Proton, European Ariane V, or US Titan IV, should be used for lifting the heaviest space station elements (15 tons) instead of the Space Shuttle, which itself weighs 100 tons.
On safety, the report said Option B has the highest risk because 311 hours of extravehicular activity by astronauts are needed in construction and 187 hours a year are required for maintenance. Also, 20 Shuttle launches are required for its construction. Extra-vehicular activity (EVA) "is an inherent risk to flight crew safety, and such heavy dependence on EVA threatens the success of station assembly. In addition, several thousand components outside the pressurized volume would require EVA for routine maintenance or replacement, and analysis indicates that the planned 187 hours per year of additional EVA for maintenance may be inadequate."
In contrast, the four international partners-Canada, the European Space Agency, Italy and Japan-favored Option B because it requires the fewest changes from the current plan. The report said, "The international partners express strong reservations about Option C based on its relative lack of maturity and programmatic uncertainties. The addition of international modules will no longer lead to the creation of a space station with greater capabilities."
The committee said the Station Redesign Team "was highly competent" and the panel had "confidence in the realism of their cost estimates."
"The redesign effort has identified viable options, with credible cost projections, which would permit the development of a very capable station while saving from 6 to 10 billion dollars over the anticipated cost of Space Station Freedom," the report said.
A version of this article appeared in the June 16, 1993 issue of MIT Tech Talk (Volume 37, Number 36).