Cooling Drag. The part of the drag of an aeroplane which is caused by the cooling system of the engine. For a liquid-cooled engine this is the drag of the radiator.
An important exception involves the air that has to flow through the engine compartment to cool the engine. A lot of air has to flow through narrow channels. The resulting friction drag — called cooling drag — ...
The other drag contributions are airfoil shape, wind induced drag, tail drag, fuselage and landing gear drag, interference drag, cooling drag and a few more.
See also: Flaps, Drag, Pitch, Thrust, Airplane