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by andlier 1908 days ago
This reminded me of the extended range with reversed ski box for tesla. https://electrek.co/2020/03/24/tesla-model-3-roof-rack-box-r...
1 comments

Ironically, this serves as an excellent refutation of the above analogy’s goal (to scoff at EMDrive experiments):

* Imagine telling a mechanic that mounting a ski box on your car with the fat/blunt end pointed forward seems to improve fuel economy vs being mounted the other way.

* The mechanic believes it’s absurd to claim you can improve fuel economy from a change that increases wind drag, so therefore your experiment is wrong since it seems to contradict established theory — case closed.

* Imagine that you more carefully measure, and find that it still seems to work surprisingly well (though also mysteriously reducing braking and cornering performance)!

* The mechanic still denies the result (which is unfair), and questions your test methodology and demands replications of the experiment (which is fair).

* Imagine someone else tries to replicate the experiment with a differently shaped ski box (i.e. not an airfoil, or with the airfoil shape vertically inverted), and fails to reproduce your results.

* The mechanic community concludes that the original result was obviously just experimental error, since the latter failure to replicate aligns with current theoretical consensus of what should happen.

In a similar way, early pioneers experimenting with winged aircraft design were laughed/scoffed at endlessly by established scientists/engineers of the era, ridiculed and crackpots wasting valuable time and resources.

The aerodynamics of the airfoil (which also explains the above ski box phenomenon) is an extremely non-obvious emergent effect, and even to this day is not as fully understood as most people probably assume.

It was an aerodynamics engineer who suggested flipping the box around.