Heavily loaded passenger jets need long runways to gather enough speed to leave the ground. Runways at some large airports are longer than 3 000m.
At night, bright lights line the runways so that pilots can find them without trouble. A system of flashing guide lights is set up beyond the runway to help pilots land safely.
Control Towers
People who work in control towers are called air traffic controllers. They direct the movements of all planes on the ground and in the air by keeping track of them on large radar screens. Air traffic controllers tell a pilot, by radio, when and where to taxi or pilot the plane down the runway.
Electronic equipment is used to guide airplanes. Long range radar is used to keep track of planes far away from the airport. This radar is called Ground Control Approach .When the airplane gets within a few miles of the runway, the air traffic controller begins to use Precision Approach Radar .This allows the controller to guide the airplane to within 0.4kmof the runway. At that point, the pilot completes the landing. Another electronic aid used in bad weather is the Instrument Landing System .In this system, radio transmitters located near the runway send guidance signals to the airplane. These signals tell the pilot how to steer the plane for the final approach to the runways. Today, there are also electronic microwave landing systems that can land the plane fully automatically.
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