The resistance of the air produced by any part of the airplane that does not produce lift. The parasitic drag is directly proportional to the size (
S), the square of the speed (
V2), the density (p) of the air, and the degree to which the body is streamlined. Parasite drag is further divided into skin friction, form drag, and interference drag. Parasite drag is directly proportional to the square of the speed. See also
skin friction, form drag, and
interference drag.