Single blade vs Two blades. Current and thrust measurements
1,232 views · Published 27 December 2014 · 1:35 · Indexed 29 October 2026
Channel: RCmags · 2014 · Entertainment
This video shows a comparison between two small, nearly identical rotors. One rotor has two blades and the other one blade. The objective of this test was to see if a single blade rotor is more efficient at producing thrust than a two blade system. I wasn't able to measure the voltage during each test, so I just assumed it was 3.7v, the nominal value of a single cell lipo. With this assumption, the single blade rotor was able to produce approximately 20% more thrust for the same amount of power, when compared to two blades: Single blade, gram force per watt: 8.51 g/w Two blade, gram force per watt: 7.12 g/w Relative increase from two blades to one blade: 8.51/7.12 ~ 1.2 120% = 100% + 20% This increase should be taken as grain of salt. The motor was not spinning at the same rpm during each test hence operating at a different mechanical efficiencies. Likewise, the voltage for each test may have been different. This comparison only serves to indicate whether a single blade can provide worthwhile reductions in power vs two blades.
