A fixed-wing aircraft is an aircraft that achieves flight by using wings to produce lift. They are called “fixed-wing” because their wings are stationary, as opposed to rotary-wing aircraft, which generate lift by rapidly spinning rotors or blades. To work properly, the wings of an aircraft have to attach to a structure. In the case of fixed-wing aircraft, the aircraft wings are attached to the body of the aircraft, known as the fuselage. There are three types of fixed-wing aircraft fuselage structures: Truss, Monocoque, and Semimonocoque.