This section presupposes a goal of supporting the International Space Station (IIS) as designed. Given the investment already made in this project, it is at least politically imperative that it reaches its full potential. While we can argue about the unrecoverability of sunk costs and the questionable research value of the end product, the IIS, like the Space Shuttle program after Challenger, is too early in its life cycle to support abandonment. Under that assumption, this section will detail what needs to be done to bring maximum value from the project.
The first goal for IIS operations is to complete the construction of the station, past US Core Complete and on to the delivery of the European and Japanese lab components. Russian components, with the exception of the Shuttle-delivered Solar Power Tower, are outside the scope of this blueprint. As mentioned in Section I, this construction project will require 23 shuttle flights, including resupply and crew transfer missions. Assuming a resumption of flight at the beginning of 2004 and five mission per year, this will result in station completion by late 2008. After completion, European, Russian or Japanese automated vehicles can provide resupply capability, and the OSP can provide crew rotations and serve as the rescue vehicle.
The second goal for IIS operations is to increase the crew size from three to a larger number to support full-time scientists on orbit. NASA's stated goal (based on preliminary OSP specifications) is four, but a crew of six will provide for more science and allow full-time European and Japanese specialists to operate their equipment.
The original IIS plan (or at least a long-adopted version of the IIS plan) called for a crew of seven, a crew return vehicle supporting that crew and a six-person habitability module attached to the nadir port of Node 1 (Unity). To save costs, NASA has cut the crew return vehicle (and now resurrected it as the OSP) and the Hab module. Possibly, they intend to support a crew of four by converting a second science rack in Destiny to support a crewmember, further lowering the research capacity of the station.
Some sort of crew module is necessary to support a crew of six. It is unlikely that a full-blown, affordable Hab module will emerge from NASA (if an airlock costs $650 million and a 14.5 tom "structural member" costs more than half that, imagine what that Hab would cost). Instead, two cheaper options can achieve that goal. The obvious option is to convert one of the Italian Logistics Modules to hold three or four crew racks and supporting equipment. After 2008 if the shuttle leaves service, these modules won't be necessary for resupply and one of the last shuttle missions could attach this module to the station. A second option is to develop a cheaper module for support of three or four crewmembers, either a converted Russian TKS-based module (like the Zarya FGB module) or a stripped down version of the MiniMir module detailed below in Section III.
Support for a crew of six could be provided by a rotating set of Aquila spaceplanes, with one mission dedicated to each expedition crew. Assuming a mission duration of 120 days, this calls for only three Aquila launches per year, but with overlapping crew exchanges and maintenance needs, this would require a fleet of three spaceplanes to support. Contingency support using multiple Soyuz vehicles is possible, with six vehicles launched each year to support overlapping crews of three, but such an arrangement presupposes a more robust Russian space program.
The final analysis of the success of the IIS project will be based on the science derived from the station. After full construction and staffing, some ten years after initial construction, the station should enjoy at least five years of stable operations, staffed by three full-time scientists year-round. Hopefully these fifteen plus person-years of research will justify the expense of this project. To increase the odds of this occurring, research conducted aboard the ISS should be chosen, managed and reviewed by recognized scientific bodies. After construction or perhaps even earlier, NASA should step back from day-to-day science and focus on station operations.
NEXT: Section III
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