From: gcowan@eagle.ca   
      
   Allen Meece included:   
   >   
   > < not necessarily pressure fed - that flies straight up, releases the   
   > second stage, and flies straight down to land at the launch site.>>   
   >   Something like >80% of the system's total fuel is spent to obtain the   
   > horizontal component of orbital flight.   
   >    Thus, the booster would get a few hundred miles down-range ...   
      
   In other words, the OP did not understand his question.   
      
   I also think straight up and straight down,   
   for a first stage with a throttleable motor,   
   are interesting. That is to say,   
   the booster is controlled to stay at or very near *zero*   
   miles downrange throughout its flight.   
      
   All it does is put the upper stages up where the air is,   
   in expansion-nozzle terms, close enough to gone.   
   They do all the horizontal component.   
      
      
   --- Graham Cowan   
   http://www.eagle.ca/~gcowan/Paper_for_11th_CHC.doc --   
   "Boron: A Better Energy Carrier than Hydrogen?"   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)