Helicopter, or rotary-wing, flight is distinctly different from traditional air, or fixed-wing, flight. An airplane by its design wants to fly, and if it does not experience any unusual interference, it will fly. A helicopter, by nature, does not want to fly. It stays in the air through a variety of forces and controls that all work in opposition to one another. If this balance of forces, which is quite delicate, is interrupted, a helicopter will stop flying immediately with disastrous results. Unlike a plane, a helicopter never glides. The main distinction between helicopter and airplane flight comes from the aerodynamics of rotary wing flight, i.e., the rotor systems. The rotary wing is rotated on a helicopter in order to achieve lift. Any aircraft that utilizes a rotary wing is known as a rotorcraft. There are three types of rotorcraft: the autogyro; the gyroplane; the helicopter. Helicopters offer advantages over traditional aircraft. For example, they are able to fly at low speeds and can hover. They also have the advantage of being able to take off or land in restricted areas traditional aircraft cannot. While the rotary wing makes the helicopter fly differently than a traditional aircraft, a helicopter still operates on principles similar to traditional air flight. In the most basic of terms, “the helicopter flies by replacing the fixed wings of the ‘normal’ airplane with a set of rotating wings – the rotor blades. When moving through the air the rotors generate lift. The lift generated can be controlled and manipulated by the pilot in order to provide motion in almost any direction.”
While helicopters are relatively modern phenomena, the principles upon which they work and a design for them have existed since ancient times. For example, the Chinese were the first to record the idea of rotary-wing flight as early as the fourth Century AD. While the Chinese only laid out the design for a toy, the ...