What's the "een" in Halloween?
airplane with two wings, one above the other. In the 1890s this configuration was adopted for some successful piloted gliders. The Wright brothers' biplanes (1903-09) opened the era of powered flight. Biplanes predominated in military and commercial aviation from World War I through the early 1930s, but the biplane's greater maneuverability could not offset the speed advantage of the lighter monoplane. After World War II, biplanes were used only for special purposes: crop dusting and sport (aerobatic) flying.