Technical Writing -- Helicopter Description

Technical Writing -- Helicopter Description

The CX2 model helicopter is a fully operational (i.e. air-worthy) miniature version of a modern helicopter. It is capable of fully controllable flight using the same general principals as full-size modern operational rotor craft. The unit consists primarily of a body housing a power unit, a microwave signal processor, and a rotational motor connected to aerodynamic propellers via a vertical cylindrical shaft. The propeller blades themselves are variable pitch in the same manner as full-size helicopter main rotor blades.

Detailed Description

The overall appearance of the CX2 helicopter is very similar to full-size helicopters with a few significant differences. First, virtually all full-size operational helicopters have tail rotors mounted to rotate in a vertical plane at right angles to the rotational plane of the main horizontal rotors. That is because without a centripetal force to counteract the torque generated by the main rotor, the rotating propeller would cause the main body of the helicopter to begin spinning in the opposite direction by virtue of Newton's Third Law of Motion: "For every action there is an equal and opposite reaction." The rear rotor spinning in the vertical plane stabilizes the body of the helicopter against those dynamic forces.

Instead of a vertical tail rotor, the CX2 uses an entirely different mechanical system for negating the effects of centripetal force and Newton's Third Law. Specifically, the CX2 uses a dual rotor system in which two main sets of rotors operate on the same shaft but rotate in opposite directions. The counter-rotating main propellers achieve the same function as the traditional tail rotor, with each propeller canceling out the torque generated by the other through centripetal force.

The individual propeller blades are aerodynamic in that their leading edges are teardrop-shaped from the horizontal plane in their direction of travel when the shaft is rotating. In effect, each propeller blade is a miniature air foil designed to maximize air pressure underneath the wing by creating a velocity differential between the air passing over and above the wing, respectively. In principle, the teardrop-shaped or laminar-flow wing is a technological application of Bernoulli's law of gaseous flow.

To permit the craft to be maneuverable, helicopters allow the pilot to vary the pitch of the individual rotors; this enable precision control over forward air speed and enables rotor craft to hover relatively motionless in three dimensional air space. The CX2 allows the operator to transmit system control inputs through microwave signals received by its control unit. There is a third rotor-like apparatus stabilizer option that can be installed above both main horizontal rotors. Unlike the two main rotors, the stabilizer "blade" is not aerodynamic; it consists of a very thin cylindrical shaft designed not to disrupt airflow substantially with two weighted tips at its ends.