While I haven't heard of a firm plan to field a crew transfer vehicle, it certainly would be a smart addition to the "fleet". A cheaper method of transport to the station would be very beneficial, especially if its use did not require one to learn Russian! I doubt if such a vehicle could be developed and launched into operation in less than five years, though (especially if NASA is directing the effort!). In the event of a shuttle loss, i don't think we would back away from Shuttle completely and await the development of a new vehicle - I don't think we could afford to.
My own personal opinion of the aftermath of another catastrophic accident is timeframe-dependent. Should one occur within the next five years or so, I would think that a shuttle return-to-flight would be implemented as quickly as possible, due to the needs of ISS. Beyond that, other partners' logistics vehicles should become available that would mitigate the loss of the shuttles' services. I don't think we would see a complete stand-down from STS operations; the infrastructure is just too valuable and, in a very real sense, irreplaceable. Shuttle gives us a great deal of flexibility in space operations, only offset by the high operating cost. Against the far higher cost of developing a replacement, though, the operating costs are acceptable.
-Kim-
****my opinions, not my employers'****
Space/Science » in reply to A spooky scenario concerning STS
Re: A spooky scenario concerning STS