Spinner (aeronautics)

A spinner is an aircraft component, a streamlined fairing fitted over a propeller hub or at the centre of a turbofan engine.

Spinners both make the aircraft overall more streamlined, thereby reducing aerodynamic drag, and also smooth the airflow so that it enters the air intakes more efficiently.

Small plates are usually fitted behind the propeller to fill in the spinner dome cutouts and are secured to the backplate again with screws.

[2] The first spinners were fitted to aircraft in the early 1910s, originally to reduce drag caused by the large-diameter rotary engines of that era, and also were prominent on World War I-era aircraft, like the Morane-Saulnier N French monoplane fighter, and for the Central Powers, Robert Thelen's Albatros D.I through D.V series of fighter designs.

In some cases spinners were found to block airflow to the engine, causing overheating,[4] a problem later solved by careful aerodynamic design.