Today we consider streamlining to be practically synonymous with aeronautical design, but it was only around 1930 that airplane designers began to take it seriously. Streamlining means reducing form drag. It takes two forms. One is the selection of an airplane’s basic shape, including the placement and shaping of windshields, nacelles, wings, empennage components and intersections, and the distribution of the cross-sectional area from front to rear, all intended to provide air with as smooth and direct a path as possible from nose to tail. The other is detail design — the fairing of fixed landing gears, inlets and outlets for engine- and cabin-cooling air, and lots of small items, such as antennas, door handles, flap hinges, tank drains and so on, to minimize the downstream disturbances they produce.