Now a days almost every city has an airport. In the case of some big cities there may be even two. Like a railway station an airport is a very busy place. At almost any hour of the day or night it throngs with people: either waiting for a flight out or who have just landed. Today, a great number of people travel from one country to another by planes. They travel just as routinely as other people move from one town to another within the same country by trains or buses.
The big building in which passengers wait for their plane is called the terminal. When a passenger arrives at the terminal, he goes to the counter of the airline which as arranged his trip. There he shows his ticket as proof that he has a seat in the plane. He also gives up his heavy luggage to be tagged and sent to the hold of the aircraft. The passenger is allowed to carry only light articles with him. If his ticket is in order, and his luggage is not overweight, he is given a card called a boarding pass. This allows him admission into the plane.
However, he cannot proceed to the aircraft until he hears an announcement that his place is about to take off.
When the announcement is made, the departing passengers go through special gates. These gates control the entrance and exit of people. At these gates, they have to show their passports to the officers in charge. They are also checked to see that they are not carrying any firearms or other dangerous weapons. Then they are allowed to go to the waiting aircraft.
Aircraft land and take off on a runway made of concrete. The runway of a modern airport is about three kilometers in length. Large jet planes take this distance to get airborne, or to come to a standstill after landing. Only one plane can land on or take off from a runway at a time. The landing and take-off of aircraft are strictly controlled by specially trained officers. These officers sit in the control tower of the airport. These air-traffic controllers, as they are called, communicate with the pilots of planes by radio. A mistake made by a controller in the tower may lead to a serious accident in which a large number of people may be injured or killed.
At night, the runway is lit hundreds of lights so that the pilot of an aircraft can see it clearly. Most modern planes are fitted with radar devices. These enable them to land even in bad weather when the runway cannot be seen clearly.
