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Off the Ground: How do We Find Where We are Going?

Scientists who are concerned with such a problem generally agree that birds have some kind of so-called «second sense» that al­lows them to fly over land and water without getting lost. Indeed, birds are always able to find their destinations and make a return fly without any trouble at all.

But people need help in finding their destination when piloting their own airplanes. This, of course, is called navigation.

Navigation is the art of finding your way from where you start to your destination. Whether used by the seamen, explorer or the pilot, navigation falls into three basic categories: dead reckoning (счисление пути) which is the basis for all navigation, celestial navigation which is flying by the aid of the sun and other stars, and radio and radar navigation.

Several different kinds of aeronautical maps provide all the de­tails which might be needed by the pilot. And hundreds of radio navigation stations are located at different places around the world to help guide the pilot. All the pilot needs to do is to tune to these radio transmitters and he will get the directional signals he needs. Distance measuring equipment now used in many airplanes tells the pilot exactly how far he is from a radio station and at what speed he is travelling over the ground.

When certain types of weather prevent the pilot from seeing the ground, additional radio transmitters let him make his approach to an airport by simply watching his flight instruments and his radio receiver indicators. These receivers help the pilot descend on the runway, thus landing at an airport even though he cannot see the ground.

At the world's larger air terminals airplanes are provided with radar guidance as another means of guiding the pilot to the destina­tion. With the help of an electronic transponder (ретранслятор) in each airplane which shows it on the radar screen, radar controllers guide hundreds of airplanes to landing.

Because of the great improvement in electronic and radio navi­gation equipment, flying to where you are going is done as effi­ciently as the birds do it and much more scientifically.

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