21.   One work is made from airplane wings.

22.   Say, for instance, an engineer in Atlanta is designing a new airplane wing, but the fuselage is being designed by a colleague in Seattle.

23.   Some of the more intriguing applications now in the lab include an airplane wing that can maneuver without the aid of either ailerons or rudders.

24.   Such programs examine successive generations of solutions to problems and choose the best ones, whether the problem is scheduling workers in a factory or building an airplane wing.

25.   The Brainy Bunch gets ambitious and builds a full-sized glider using old airplane wings.

26.   The design, whose vanes have a cross-section like an airplane wing, was efficient but unstable, tending to break easily because of extreme vibrations.

27.   The silver iodide can be released from ground-based generators or from flares attached to airplane wings.

28.   The world is awash in space-age materials, from the graphite panels of an airplane wing to the honeycomb sandwich of a skateboard.

29.   The travel agency and ticket counter boasts a full-size replica of an airplane wing and a giant life preserver jutting from a wall.

30.   These vortices provide lift to the falling sheets, much the way air passing over an airplane wing creates lift.