From: henry@spsystems.net   
      
   In article ,   
   Charlie  wrote:   
   >...In addition to allowing airlaunched small (<100) ton   
   >rockets to deliver very substantial payloads, very high ISP's would   
   >also permit rocket engineers to consider the concept of killing most   
   >of your orbital velocity under power before beginning reentry.   
      
   Bear in mind that you have to be able to do a reentry without this, to   
   cover abort cases.  That considerably reduces the benefit.   
      
   Note also that we know how to build lightweight, reliable heatshields with   
   large safety margins, provided they don't have to be reusable.  And the   
   technology is *nearly* in hand to do the same for reusable systems...   
   provided you don't insist on them having wings.   
   --   
   "Think outside the box -- the box isn't our friend."    |   Henry Spencer   
                                   -- George Herbert       | henry@spsystems.net   
      
   --- SoupGate-Win32 v1.05   
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