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.

At a press conference this month, Dr Chen Yue, the head of the communication satellite division at the China Academy of Space Technology, said his country has been studying EM Drives since 2008. In repeated tests, the thrust output has been shown to be real, he claimed.

“National research institutions in recent years have carried out on the EM engine of a series of long-term, repeated tests, the NASA published test results can be said to re-confirm the technology,” Dr Chen said, according to Science and Technology Daily.

The EM Drive, proposed in 2000 by British inventor Roger Shawyer, is powered by electricity and doesn’t need a propellant to move. It also appears to break Newton’s third law of motion because it generates thrust – albeit in tiny, tiny amounts – without a reaction in the opposite direction. Shawyer’s theory was laughed off by scientists as impossible, although a growing number of boffins are now working on such drives and they appear to have had some positive results.

Having such a drive would open up new possibilities in space travel since it allows thrust to be generated using electrical power alone. With no heavy propellant needed, and just the Sun’s rays on solar cells, satellites could maneuver without having to worry about running out of fuel, Solar System probes would have extended ranges, and the engines, used in concert, may even power human exploration.

While such drives produce only a tiny fraction of the raw power produced by chemical rockets, or the more modest output of ion drives, the ability to operate without fuel makes the possibilities very exciting. Don’t forget, in the vast obsidian vacuum that is space, you don’t need a lot of thrust to move. Today’s EM Drives can produce a few millinewtons of thrust, according to tests, although a decent-sized satellite needs a little more than that to get going, so more work is needed. Scientists also need to figure out how it actually functions.

NASA has tentative plans to take an EM Drive out for a spin in Earth’s orbit by 2018. Dr Chen said China has already done so. He didn’t give more details but it seems likely the Middle Kingdom version of the EM Drive is being tested on the country’s Tiangong-2 space lab.

China is trying out different shapes for the reaction chamber of the drive to see which generates the most thrust. It’s clear that the country is taking the EM Drive seriously and wants to get one operational as soon as possible.

“This technology is currently in the latter stages of the proof-of-principle phase, with the goal of making the technology available in satellite engineering as quickly as possible,” said Li Feng, chief architect of the China National Space Technology Institute’s communications satellite division, at the press conference.