The very early model airplanes were all free-flying. That is, once they were launched, there was no way to control their flight. Free flight remains a very popular activity today. To many modelers there is nothing quite so beautiful as the sight of a model drifting freely on a gentle breeze. But it is not fun to lose a model if it flies too far. The wise free-light flier sets the rudder on the airplane to produce a gentle turn. This keeps the model flying in circles overhead. Free-flight models can be divided into three types: gliders, rubber-powered, and engine powered. Gliders are relatively simple. They are launched into the air either by being thrown or by being towed on a string (like a kite) and then released for free flight. The towline is attached to a hook on the bottom of the glider. When it reaches altitude, the line is slackened, allowing it to slide off the hook. The glider is then free to soar like a bird.
Rubber-powered models have propellers that are turned by wound-up rubber bands. When the rubber unwinds, it turns the propeller, which causes the airplane to move forward through the air. Some rubber-powered models are very small, with wingspans of no more than 30 centimeters (12 inches). Others have wingspans of close to 2 meters (6 feet). A very special type of rubber-powered model airplane is designed to be flown in large rooms indoors. These super-lightweight models can fly for almost an hour at a time.
Rubber-powered models have propellers that are turned by wound-up rubber bands. When the rubber unwinds, it turns the propeller, which causes the airplane to move forward through the air. Some rubber-powered models are very small, with wingspans of no more than 30 centimeters (12 inches). Others have wingspans of close to 2 meters (6 feet). A very special type of rubber-powered model airplane is designed to be flown in large rooms indoors. These super-lightweight models can fly for almost an hour at a time.
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