Today’s Aircraft

Commercial aircraft are built for strength and safety rather than speed, although many can travel at just below the speed of sound. A modern airliner can fly nonstop from San Francisco to Sydney, Australia; from Washington, D. C., to Rome, Italy; or from New York

City to Tokyo, Japan. It can cruise high above the clouds at over 600 miles per hour (965 kilometers per hour).

Most airliners have turbofan engines, powerful enough to lift a payload of 400 tons (363 metric tons) or more. Each engine of a Boeing 747, for example, generates about 50,000 pounds (22,700 kilograms) of thrust-about the same as the two engines of an F-15 fighter. Four engines provide insurance against engine failure, but modern engines are so powerful and reliable that many modern airliners, such as the Boeing 777, make do with two.

Commercial airplanes with piston or turboprop engines are still used, too. Propeller planes, although slower than jet planes, are quieter and cheaper to run. They can also take off and land from small airports.

Private airplane owners fly light air­planes, carrying between two and ten people, for business and pleasure. U. S. manufacturers, such as Beech, Cessna, and Piper, have built many of the world’s most successful light aircraft. Modern business planes, with jet engines, carry five to ten passengers, and they cruise at much the same speeds as jet airliners.