Predicting which propellers are best to use for your rc quad copter project can be difficult. Computer programs such as MotoCalc can work, but in many cases efficiency predictions can be off by a large amount. Propeller design is an extremely complicated problem, and the best approach is often to test a large set of propellers on a static thrust stand and measure their performance experimentally.

Finding a unified source for this data is also difficult. A group from the University of Illinois have done static testing on small propellers (less than 5 inches), suitable for building micro quad copters with. The paper is available for download, and the important results are on page 5. The have obtained what is called a “Figure of Merit” (FOM) for each propeller, which is the ratio of the ideal power required to hover to the experimental result. The better the propeller is, the closer this ratio is to one. Working from this, you can do some simple algebra to get the coefficients of thrust and power from their results. This data should help you make a good propeller choice for your RC quad copter project.

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