Propeller (aeronautics)

In aeronautics, an aircraft propeller, also called an airscrew, converts rotary motion from an engine or other power source into a swirling slipstream which pushes the propeller forwards or backwards. It comprises a rotating power-driven hub, to which are attached several radial airfoil-section blades such that the whole assembly rotates about a longitudinal axis. The blade pitch may be fixed, manually variable to a few set positions, or of the automatically variable "constant-speed" type.

The propeller attaches to the power source's driveshaft either directly or through reduction gearing. Propellers can be made from wood, metal or composite materials.

Propellers are only useful at subsonic airspeeds generally below about 480 mph (770 km/h), although a speed of Mach 1.01 in a dive was achieved, with a propeller efficiency of 78%, by the McDonnell XF-88B experimental propeller-equipped aircraft.

This article is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.