Which type of drag is caused by the shape of the aircraft?

Form drag is indeed the type of drag that is primarily caused by the shape of the aircraft. This drag occurs due to the pressure difference created as air moves around the aircraft's surface. When an aircraft is in motion, its shape determines how efficiently air can flow around it. A more streamlined shape tends to reduce form drag, while a less aerodynamic shape increases it.

In the context of aviation, form drag plays a significant role because it directly affects the overall aerodynamic efficiency of the aircraft. For example, an aircraft with a smooth, contoured surface will experience less form drag compared to one with a boxy or irregular shape.

Parasite drag is a broader term that encompasses all types of drag not associated with lift, including form drag and skin friction drag. Skin friction drag specifically refers to the friction of air molecules against the surface of the aircraft, which is influenced by the texture of the surface rather than its shape. Induced drag, on the other hand, is related to the generation of lift and is a byproduct of vortex formation at the wing tips, thus making it distinct from drag caused by shape.