While I was on vacation there were some ripples in twitter-land about NASA announcing a rocket propulsion system that didn’t need fuel. Here’s a representative sample: ‘Impossible’ Space Engine May Actually Work, NASA Test Suggests

Sadly, no. And I say sadly not because of disappointment that gizmos that can’t possibly work don’t end up working, it’s that NASA was involved and gave this two thumbs up. They need to be better than this.

This being the internet, rebuttals to the NASA report already exist. The one from John Baez is pretty good

The tl;dr version. Lots more detail in the link.

1. They tested a device that was designed to work and one that was designed not to work. They both worked.

2. They tested the devices in a “vacuum chamber”, but they didn’t take the air out.

3. They didn’t carefully study all possible causes of experimental error… like their devices heating the air.

That first one is mind-boggling. It’s as if you weighed something at two pounds, and when the scale was empty, it read two pounds, so you conclude the test object weighs two pounds. (Insert joke about not having to be a rocket scientist to understand calibration runs. But … apparently it helps to not be a rocket scientist, in this case) That’s some sloppy science.

So, no. You can’t get from

Thrust was observed on both test articles, even though one of the test articles was designed with the expectation that it would not produce thrust.

to

Test results indicate that the RF resonant cavity thruster design, which is unique as an electric propulsion device, is producing a force that is not attributable to any classical electromagnetic phenomenon and therefore is potentially demonstrating an interaction with the quantum vacuum virtual plasma.