NACA cowling


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NACA cowling

A type of cowling most widely used on reciprocating radial engines. It is a drag-reducing annular cowling whose trailing edge fairs smoothly into the fuselage or the engine nacelle. The airfoil shape of a cowling produces a forward dynamic force that more than compensates for the cooling drag of the engine.
References in periodicals archive ?
An early success was the NACA cowling which significantly improved aerodynamic efficiency without degrading cooling.
This section of the exhibit includes rare handcrafted wooden models from the 1930s, such as that for a prototype Navy seaplane, the Stearman 85 or XOSS-1 of 1937, showing the streamlined NACA cowling surrounding its engine.