Most of us spend little time thinking about the impact that the helicopter has on our lives - except perhaps when we are listening to the traffic report on our local radio station as we are rushing to class or to work. But helicopters have revolutionized a number of areas of modern life from the way in which we drive to the way in which we treat heart-attack victims to the way in which we fight wars. There are a wide range of helicopters from diminutive two-seaters to massive military carriers. Both size and shape are in large measure determined by the mechanics of being rotary-wing aircraft (as opposed to the "fixed wings" of airplanes). All helicopters operate by producing thrust through the blades of a main rotor that spin above the body (or fuselage) of the helicopter. As the main set of paired blades rotate, they create an airflow above them. This in turn creates lift, which raises the helicopter off the ground. The same rotor blades that provide the lift can be controlled by the pilot to determine the direction that the helicopter moves - forward, backward, sideways. Although helicopters fly much less quickly than the faster fixed-wing aircraft, the fastest helicopters can achieve speeds of over 200 mph (Crawford 14).
Helicopters serve important functions in both civilian and military arenas. Although the ways in which they are put to use in these two different arenas of American life are substantially different from each other at least on a superficial level, the way
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