COMPARISON OF TEN SAIL BOAT PROPELLERS

This study investigated the performance characteristics of ten different commercially available propellers typically seen on auxiliary sailboats. Included in the testing were two feathering propellers, three folding propellers, one self-pitching propeller, and four fixed-bladed propellers. All propellers were of the same pitch and diameter. Testing at the MIT Marine Hydrodynamics Laboratory consisted of three common boating situations: forward boatspeed, forward rotation (normal forward operation); forward boatspeed, reverse rotation (backing down); and forward boatspeed, no rotation (drag under sail). It was found that all ten propellers performed generally well in forward operation, but that large differences in performance existed in reverse and in drag. The text of this report is written with the lay audience in mind.