In major international tests, the physics-defying EmDrive has failed to produce the amount of thrust proponents were expecting. In fact, in one test at GermanyĆ¢(TM)s Dresden University, it didn’t produce any thrust at all. Is this the end of the line for EmDrive? Popular Mechanics: The crux of the EmDrive is if you bounce microwaves around inside the tube, they exert more force in one direction than the other, creating a net thrust without the need for any propellant. And when NASA and a team at Xi’an in China tried this, they actually got a small-but-distinct net force. Now, however, physicists at the Dresden University of Technology (TU Dresden) are saying those promising results showing thrust were all false positives that are explained by outside forces. The scientists recently presented their findings in three papers at Space Propulsion Conference 2020 +1, with titles like “High-Accuracy Thrust Measurements of the EmDrive and Elimination of False-Positive Effects.” (Other two studies here and here)

Using a new measuring scale and different suspension points of the same engine, the TU Dresden scientists “were able to reproduce apparent thrust forces similar to those measured by the NASA team, but also to make them disappear by means of a point suspension,” researcher Martin Tajmar told the German site GreWi. The verdict: “When power flows into the EmDrive, the engine warms up. This also causes the fastening elements on the scale to warp, causing the scale to move to a new zero point. We were able to prevent that in an improved structure. Our measurements refute all EmDrive claims by at least 3 orders of magnitude.”

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Source:: Slashdot