The observation has been made (I don't know how accurate it is) that satellite capture and repair, and especially earth return and relaunch, is really too expensive to be worthwhile in the first place... "Hubble/Solar Max (etc.)could have been replaced for less than the cost of the repair missions... we need to be thinking more about what we actually want back from space."
As I said, I'm not sure how completely I agree with this, but it occurs to me that "heavy return" does seem to be one of the more difficult mission modes... heavy lift, and manned lift and return, are comparatively easy by comparison. (Apollo was heavy lift/manned return, but not heavy return...) The Shuttle was a good design, given its mission: do everything with exactly one spacecraft type. The big mistake was trying to do everything with exactly one spacecraft type. We need big cheap heavy-lifters - possibly expendable, possibly reusable. (Try to get the expensive bits back, like the recoverable engine assembly of the "Shuttle C" concept? Invest in manufacturing infrastructure such that single units become dirt cheap, like beer cans or butane lighters? I'm not sure at this point.) We need small manned orbiters, like space-going fighter planes: reentry-capable, robust and logistically agile... with the resiliency of good military hardware. "Marine-proof", as Randall would say. We may need something like the Shuttle for the rare cases where you actually need to bring a large heavy payload back down. (It might be a more cost-effective heavy-lander if it always went up empty to bring something back... perhaps the payload volume could then be used for ascent propellant... probably with a denser fuel than hydrogen!). This is somewhat orthogonal to the "manned vs. unmanned" question: It may well be better for the heavy cargo vehicles to be piloted, but it's likely to make everything cheaper, safer, and more versatile if the big, fragile heavy-lander isn't the prime option for personnel transport to and from orbit. (I envision that one with a single seat, occupied by a pilot who might possibly be drawing a "hazardous duty" bonus on his flight pay...) -dave w _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
