Rib (aeronautics)
In an aircraft, ribs are forming elements of the structure of a wing, especially in traditional construction. By analogy with the anatomical definition of "rib", the ribs attach to the main spar, and by being repeated at frequent intervals, form a skeletal shape for the wing. Usually ribs incorporate the airfoil shape of the wing, and the skin adopts this shape when stretched over the ribs. Type of ribs. There are several types of ribs. Form-ribs, plate-type ribs, truss ribs, closed-ribs, forged ribs and milled ribs, where form-ribs are used for light to medium  loading and milled ribs offer the greatest strength. Ribs are made out of wood, metal, plastic, composites, foam. The wings of kites, hang gliders, paragliders, powered kites, powered hang gliders, ultralights, windmills are aircraft that have versions that use ribs to form the wing shape. For full size and flying model aircraft wing structures that are usually made of wood, ribs can either be in one piece (forming the airfoil at that rib's "station" in the wing), or be in a three-piece format, with the "rib web" being the part that the one-piece rib consisted of, with  capstrips for the upper and lower edging of the rib, running from the leading edge to the trailing edge, being the other two component parts.