Parasite Power

Parasite power is the power required to overcome the drag of the body. Engineers view this as `parasitic' in an airframe because the passengers, cargo and pilots are not directly contributing to powered flight. The power required to overcome the body's drag is the force required to push the air in front of the body ( $$C_{Db} \rho v^2 A_b /2$$) times the velocity ($v$) that force is applied at, or

$$P_{par} = \frac12 \rho \ v^3 C_{Db} A_b.$$