Randall Clague wrote: > On Sun, 2 Feb 2003 01:18:58 -0800, [EMAIL PROTECTED] (Julie Porter) > wrote: >>Vehicals of the DCX or Pogo class, have to cary enough fuel for re-entry >>right? That they use the thrust to counteract the gravitational returns? > > Retrofire and landing fuel. Retrofire about the same as any other > bird for the same orbit, landing fuel generally considered to be the > equivalent of 240 to 300 m/sec delta-v.
That's with aerobraking to remove most of orbital velocity, right? > One thing that deserves mention, in light of the shock with which > NASA's calm comments about being unable to inspect the TPS or repair > it if they did find a problem with it have been received, is that an > SSTO will have even less margin than Columbia did. True, an SSTO will > have a lower heat load than Shuttle and probably lower peak heating as > well. But if anything goes wrong with the TPS on an SSTO, it better > just stay up there. Until we send another to go fetch the crew and/or repair the SSTO. Which, I believe, might have been possible here had NASA thought of it. >>I have never liked ablative methods. Yet they seem to be the best. > > I have a simple philosophy: Do What Works. Ablatives work. Until they ablate away or fall off. BTW, question about the shuttle tiles. I was talking to my dad about this earlier today, and he mentioned that the white tiles used for the shuttle's upper body would make great housing material except for the cost: excellent insulators, totally fire and termite proof, strength to weight ratios far more than adequate for a typical house, et cetera and so forth. The only problem would be cost - which, of course, is often a killer for this kind of thing. But he was wondering if, perhaps, getting some contractors hooked on using these for housing materials would drive the point down, such that making them for the occasional spaceship would be a cheap custom job rather than the elaborate undertaking it presently seems to be. (Then again, that might not be inherent to the material, just to its current main user.) _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
