<blockquote><font class="small">In reply to:</font><hr /><p>> The X-33 propellant tnk had been built but failed during testing. More at: <p><hr /></p></p></blockquote><br /><br />Yes, and the usual retort is "But, but, VentureStar was going to use metal tanks!" Even that doesn't hold water, so to speak. LockMart's plans never produced a mass-fraction that would allow VentureStar to work as SSTO or Stage-and-a-Half. By the end of their viewgraph parade, VS had a "carrier" on it's back for a second stage and payload. The X-33 wasn't underbudgetted, IMHO, it was improperly managed. Lockmart had 50x the funding that Scaled Composites had for SS1, and never flew anything for X-33. I only bring up the comparison as they were both supersonic, suborbital craft, and the Burt Rutan is a G0D.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>> But missions to mars would probably not happen for the purpose of exploration under private industry. They will go for exploitation if that yeilds a profit. <p><hr /></p></p></blockquote><br /><br />I think you might confuse private industry and private enterprise? There are plenty of private (and very wealthy) citizens ponying up money to make spaceflight happen, not all are looking directly for profits. People will go places for the adventure and other reasons (solitude, no beginnings, etc) To claim that the profit-motive is the only thing driving the new Space Age is to only see a small part of the movement. <br /><br />Is there money to be made/around Mars? Someday.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>> I have seen a tendency here from folks here at SDC to criticize NASA as overbloated, wanting only to develop new tech yet untested companies are going to do this or that when they say they will. The fact is, we won't know for certain how much of the human spaceflight work private enterprise will be willing to take over. If they see profit potential in going to the asteroids or the martian moons then it wil</p></blockquote> <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>