XPost: sci.space.shuttle, sci.space.history, rec.aviation.military   
   From: tomswift@cruzio.com   
      
   In article <344c$4404cc44$927a2cf9$14190@FUSE.NET>,   
    "H2-PV NOW"  wrote:   
      
   > > Wings are cheaper than fuel. Before last year's oil price gouging   
   > > carbon-fiber fabric was down to $0.94 square foot for 6kx6k 2,000,000   
   > > psi, wholesale in volume lots. The cost of 10,000 square feet of wings   
   > > in material costs was less than buying a Piper Cub used. Now Exxon got   
   > > their price raise and it costs a NEW Piper Cub.   
      
   Comparing an air breathing winged vehicle to a VTVL all rocket vehicle   
   the VTVL has the following advantages.  Low landing speed of about 3   
   mph, vs 220 mph for a winged lander.  The vehicle has about 10% less   
   hardware (no wings or wheels).  Because there are no wings or wheels   
   they can't fail (Shuttle). Hardware costs are in the neighborhood of   
   $1000 per kilogram, and propellents $0.50 per kilogram.  With these   
   numbers the break even point for cost is at 250 flights per year for a   
   vehicle designed for a ten year life, and it will be a long time before   
   we have shuttles running that schedule.  No specialized runways required   
   to land.  In an emergency it can land on any firm level ground (DC-X).   
   Wings are of use only for the first two minutes of a mission, and the   
   last one minute.  Wheels are used only the last 30 seconds of the   
   flight.   
   Many engineers and managers like wings and wheels because they are a   
   known quantity. They don't like the Buck Rogers stuff, at least until   
   someone else does it, then it will be all the rage.   
      
   --   
   Mike Swift   
      
   Two things only the people anxiously desire, bread and circuses.   
                                         Decimus Junius Juvenalls   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)