Yesterday NASA announced to an unsurprised public that it had chosen its proposal for its next deep space craft (http://www.nasa.gov/home/hqnews/2011/may/HQ_11-164_MPCV_Decision.html ). The MPCV or multi-purpose crew vehicle to give it its full name will consist of, for those of you that don't know, the re tasked machine that was already under construction and testing known as constellation/ Orion. This was the ill fated and woefully underfunded "brain child", and I do use the word loosely, of Ex president G. W. Bush for his attempt at a moonshot. When the new administration came in and further funding did not materialise the focus was shifted to deep space exploration. At the same time private companies were invited to tender to provide a ferry service to the ISS.
The way this system will work is that the main parts of the MPCV and any lander required will launch on top of a heavy life variant of the Ares rocket, followed a few days later by an Orion capsule carrying the crew riding another rocket. The two parts will then combine in orbit before setting of to the designated target. There it will complete its mission before returning to earth where the Orion capsule will return the crew in a splash down in the Pacific Ocean, Apollo style.
Now here is where I think NASA have missed a trick. The most expensive and risky part of any space mission is during the Launch. Why have a crew vehicle that can only be used once? Why not have a vehicle that can return to orbit be re-supplied before beginning its next mission?
Sound like science fiction? I don't think so and here's why. We already have a reusable multi-mission vehicle that can be re-crewed and re-supplied in orbit. The ISS does this and more already. The MPCV already has the ability to dock because it needs to assemble itself in space so why not dock it on its return from deep space. Its crew could then enter the ISS and catch a ferry flight back to Earth leaving the MPCV to be resupplyed by the robotic Progress modules that currently resupply the ISS. Once resupplied a new crew could be ferried up to the ISS to then prepare the MPCV for its next mission meaning only one launch per mission and as the crew were not intending to continue in the launch vehicle the extra room in the capsule could bring more supplies.
I don't deny that there are some technical issues to overcome. Orbital insertion from an inward bound trajectory would require some fancy maths. The craft would need to have the fuel to preform orbital maneuvers in order to catch and dock with the ISS but the fact is there would be a reusable vehicle there rather than have the cost of lugging a vehicle and the fuel it needs just to get it into orbit so costs would be vastly reduced. Could the ISS be adapted to this new role? Well it is a modular design that can be adapted to fit its role so I don't see why not.
Isn't it time our use of disposable ships ended?