A radio-controlled (model) aircraft (often called RC aircraft or RC plane) is a small flying machine that is controlled remotely by an operator on the ground using a hand-held radio transmitter.
The transmitter communicates with a receiver within the craft that sends signals to servomechanisms (servos) which move the control surfaces based on the position of joysticks on the transmitter.
The control surfaces, in turn, affect the orientation of the plane.
Flying RC aircraft as a hobby has been growing worldwide with the advent of more efficient motors (both electric and miniature internal combustion or jet engines), lighter and more powerful batteries and less expensive radio systems.
A wide variety of models and styles is available.
Scientific, government and military organizations are also utilizing RC aircraft for experiments, gathering weather readings, aerodynamic modeling and testing, and even using them as drones or spy planes.
There are many types of radio-controlled aircraft.
For beginning hobbyists, there are park flyers and trainers.
For more experienced pilots there are glow plug engine, electric powered and sailplane aircraft.
Some models are made to look and operate like a bird instead. Replicating historic and little known types and makes of full-size aircraft as "flying scale" models, which are also possible with control line and free flight types of model aircraft, actually reach their maximum realism and behavior when built for radio control flying.
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