4 ms·

"I believe they found that for the EmDrive, the thrust was being generated by interaction of the electricity through the cables with Earth's magnetic field." is

• ben_w 8y ago
  I think what you’re missing is that the entire Earth is the reaction mass. I’ve had a bit of fun doing the maths on space launch systems that function like this — if I remember right, you might even be able to do it… if you can make a monocrystalline superconductor, of whatever the best critical current density was about five years ago, about ten times the combined mass of your payload and cooling equipment. Unfortunately there are limits on which direction this force can act in that make it even less useful than I’ve just made it seem.
• thekingofh 8y ago
  You are correct in that this does not use propellant, however the Earth would need to be nearby for this to be viable for any sort of space travel. Perhaps maybe keeping a satellite in orbit or doing orbital maneuvers, but even then the amount of thrust is so small that it would likely not be usable. So unless the review team comes back and says they've eliminated magnetic interference then we're probably back to square one.