May 25, 2018

IT ALWAYS SEEMED TOO GOOD TO BE TRUE: ‘Impossible’ EM drive may actually be impossible after all.

The idea, championed by inventor Roger Shawyer, uses trapped microwaves in a conical cavity. Previous tests by NASA showed that the microwaves bouncing off the walls of the cavity appeared to produce enough force to push the cavity in one direction. However, a group from TU Dresden in Germany has been unable to replicate these results, or at least they have, but not for the reasons NASA originally thought.

The German team copied the NASA experiment exactly, piping microwaves into the cavity, using lasers to monitor movement and a spring to measure thrust. The setup did indeed produce thrust, as indicated by the spring. But when the researchers positioned the microwaves so they definitely could ­not produce thrust in the direction of the spring, the drive pushed just as hard. Furthermore, the same degree of thrust remained even after power was cut in half. So clearly, there are other factors at play.

The team suggests that the thrust may actually be produced by an interaction between the cables that power the microwave amplifier and Earth’s magnetic field. If this is the case, it won’t work in space

Oh, well.

UPDATE (FROM GLENN): You know how to find out it it’ll work in space? Test it in space.

InstaPundit is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.