Fran Scott

THE MOST distinguishing feature of any aircraft is its shape. The world of aircraft is a realm of shapes. Each airplane is contoured so as to achieve certain desired flying qualities. In this, however, compromises must be made, for unfortunately, a form giving good high-speed characteristics will usually be a poor performer at low speeds, and fine slow flying airplanes just won't go fast at all. Slots, flaps, and various leading edge devices are commonly used to alleviate the problem, but the most spectacular solution to the dilemma of optimum aerodynamic form is to actually change the airplane's shape while in flight. To pivot the wings on a hinge really achieves dramatic results. For example: extending the wings of a variable geometry airplane enables it to take off and land on short runways, to fly slowly, and to remain airborne for great distances.