Chinese em drive test
December 22, 2016

China claims success with new ‘reactionless engine’ EmDrive

In what appears to be the latest breakthrough in space travel technology, China claims it has made a great leap forward with its ‘reactionless’ Electromagnetic Drive, or simply, EmDrive – an engine that uses only the power of electromagnetic radiation contained within a microwave cavity.

The EmDrive flies in the face of physics – going against the law of conservation of movement; producing mechanical movement but without an exchange of matter.

Originally thought up by Roger Shawyer, the EmDrive is designed to have a microwave cavity which is asymmetrical, like a truncated cone shape. The narrower end of the cone should house an electromagnetic power source; namely a magnetron which would then expel microwaves, hitting the inside of the cavity. As these waves are contained, they bounce off the walls of the cavity and in doing so creating electromagnetic resonance.

By doing so, the EmDrive’s electromagnetic field creates a force that ‘pushes’ away from the larger end of the cone, creating thrust. This opposes the idea of the conventional engine which ejects mass from within to create thrust.

Ideal for space exploration?

The China Academy of Space Technology (CAST) gave a press release on December 10 stating that the technology had been tested in their laboratories and was currently undergoing zero gravity testing in its Tiangong 2 space station.

The EmDrive creates a very small amount of thrust that's of no use on Earth-- but the vacuum of space would allow a spacecraft to reach incredibly high speeds if given enough time. In order to ensure the EMDrive’s engine performs optimally, it is critical that the cavity’s material be made to minimize electromagnetic loss through absorption into its wall. Therefore it is likely that EmDrives in the future will be made from superconducting materials to get more out of the engine.

Due to the need for refueling being eliminated, not to mention the lack of need for fuel storage, the EmDrive seems to be ideally suited for space exploration.

It should theoretically only need a power source such as a reactor or solar energy. CAST have suggested it could be used for probes sent beyond our solar system or even for manned missions to Mars. It could also conceivably pave the way for much smaller satellites, as there would no longer be the need for their manoeuvring to require chemical thrusters. The military implications are also notable, with surveillance satellites potentially lasting a great deal longer.


Image credit: Ray Shawyer