From: jimdavis2@earthlink.net   
      
   johnhare wrote:   
      
   > This suggests that there would be 550 lbs available to the   
   > 2,000 second air breather and   360 lbs available for the   
   > 1,000 second air breather. T/W ratios required would be 28 and   
   > 42 respectively for these systems to match pure rocket   
   > performance on a VTVL.   
      
   What kind of airbreathing engines do you have in mind here? If   
   turbomachinery based your Isps are too low and your T/Ws are too   
   high.   
      
   More importantly, I think if you want your airbreathers to do   
   double duty during ascent and recovery you're going to have to   
   address the issue of increased installation weight. An installation   
   optimized for deceleration/hover may not work well while   
   accelerating and vice versa.   
      
   Jim Davis   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)