XPost: rec.arts.sf.misc   
   From: chakatfirepaw@gmail.com   
      
   On Sun, 02 Aug 2015 08:30:16 -0400, J. Clarke wrote:   
      
   > In article , chakatfirepaw@gmail.com says...   
   >>   
   >> On Sat, 01 Aug 2015 18:07:57 -0400, J. Clarke wrote:   
   >>   
   >> > In article , chakatfirepaw@gmail.com   
   >> > says...   
      
   >> >> Note that I was specifically referring to the power efficiency,   
   >> >> (an ideal photon drive requires 300MW/N, the claimed figure for the   
   >> >> EM Drive is about 1GW/N).   
   >> >   
   >> > And how much does kerosene require per newton?   
   >>   
   >> On the order of 3kW/N.   
   >   
   > So what's wrong with this picture?   
      
   Nothing, power efficiency is a comparison between the power required to   
   actually get a certain thrust and an ideal drive with the same specific   
   impulse.  Ideal chemical drives top out at about 5kW/N, but that's   
   because their specific impulse sucks, (500s at best).   
      
   Meanwhile, photon drives have a specific impulse of 30,559,884s.   
      
   --   
   Chakat Firepaw - Inventor and Scientist (mad)   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)