This series of videos from Rcestflight is some nice testing of different RC boat propeller designs. It was a competition with a prize and people could send thei

This series of videos from Rcestflight is some nice testing of different RC boat propeller designs. It was a competition with a prize and people could send their designs to be 3d printed. There was at least one toroidal design as well. They could show this stuff at schools... https://www.youtube.com/watch?v=KeTh-TIhL9M https://www.youtube.com/watch?v=KeTh-TIhL9M