Paragraph on “How have jet aircraft made the world seem smaller?” complete paragraph for Class 9, Class 10, Class 11 and Class 12
How have jet aircraft made the world seem smaller?
The first jet planes were military ones. In 1952, however, the first passenger jet airliner entered service. This was the De Havilland ‘Comet’, built in Britain. Nowadays there are huge ‘jumbo’ jet airliners, like the Boeing 747, each carrying several hundred passengers. These travel at around 800 km (500 miles) per hour. Recently supersonic or faster-than-sound passenger jets have been developed. The first one to fly was the Russian Tupolev 144 in 1968. The first one to enter passenger service was the Anglo-French ‘Concorde’ in 1976. Concorde can go from London to New York in just under four hours. Jet airliners have made travel around the world so much quicker that in a way they really have made it seem smaller!
There are now thousands of airliners. Cities have huge airports where they can land. Because the aircraft are so noisy it is very unpleasant to live by an airport ! Air-traffic controllers at the airport use radar and radio to watch the hundreds of aircraft approaching and leaving. They must plan and direct the planes carefully to avoid collisions. The air–craft themselves arc now very complicated. They have instruments to tell the pilot about the plane and its engines. The altimeter gives the height off the ground ; the air-speed indicator says how fast the plane k going ; the compass gives the direction in which it is pointing. Most airliners have an ‘autopilot’ which automatically keeps the plane on a course, height and speed set by the pilot. Some even have automatic landing systems the plane can land itself!
Can aircraft fly backwards: Helicopters are not like ordinary aeroplanes. They do not get their lift from fixed wings moving forward through the air. Instead they have thin revolving wings called rotors. The motor drives the rotors round and round above the helicopter to provide lift. This means it can go forwards or backwards, up or down, or hover, as the pilot chooses. Five hundred years ago Leonardo da Vinci de-signed a helicopter. However, it was not until this century that one was built.
Modern V/STOL — Vertical and Short Take Off and Landing — aircraft can also hover and fly backwards. An example is the British Hawker Siddeley ‘Harrier’ tighter. This has a jet engine with movable exhaust nozzles, which can direct the jet exhaust downwards to provide lift when the aircraft hovers.