Total drag is the sum of which two types of drag?

• A. Parasite drag only
• B. Induced drag only
• C. The sum of the parasite drag and induced drag
• D. Skin friction drag only

Answer: (C)

In flight, the total drag acting on an aircraft is made up of two primary components—parasite drag and induced drag. Parasite drag includes all drag not tied to lift generation, such as skin friction, form drag, and interference drag; it tends to rise with speed because those frictional and form effects increase with velocity. Induced drag arises from the generation of lift itself, caused by wingtip vortices and finite-wing effects, and it decreases as speed increases because the same amount of lift can be produced with less induced flow at higher speeds. Therefore, the total drag at a given airspeed is the sum of these two components: parasite drag plus induced drag. The other options describe only one component or a subset (skin friction is part of parasite drag, but not the whole), so they don’t account for the total drag.