Single-blade propeller

A single-blade propeller may be used on aircraft to generate thrust. Normally propellers are multiblades but the simplicity of a single-blade propeller fits well on motorized gliders, because it permits the design of a smaller aperture of the glider fuselage for retraction of the powerplant. The counterbalanced teetering mono-blade propeller generates fewer vibrations than conventional multiblade configurations. Often, single blade propeller configurations are touted as having a much greater efficiency than multiblade propellers, but this is a falsehood outside of the inertial losses in spinning a heavier propeller, and the minimal additional drag from added blades. Single bladed propellers are principally used to fulfill engineering requirements that fall outside of the scope of efficiency.

Samara (fruit) single blade-like seed which autorotates in Nature.

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