How aircraft fly

The word “aircraft” means any kind of aircraft or vehicle which air can support. Airplanes, helicopters and gliders are heavier–than-air craft. They are supported by the dynamic action of the air upon their aerodynamic surfaces. Free and captive balloons and airship are supported by their own buoyancy*. They are called lighter–than–air craft. Rockets do not need air for support. They use the power of their reaction engine to propel them through space, and are called “spacecraft”.

All heavier-than-air craft use aerodynamic surfaces or airfoils to develop the necessary supporting force. These airfoils* are usually in the form of fixed or rotary wings. In order to develop the required lift, the airfoils must move through the air with sufficiently high speed. This speed is imparted to the aircraft by the thrust of its powerplant. The thrust may be developed by rotating the pulling or pushing propellers, or by throwing back masses of air by means of gas turbine engines.

To change the attitude and direction of flight aircraft use control surfaces or controls. These comprise the rudder, the elevator, and ailerons. The rudder is used to deflect the movement of the aircraft to the left or to the right. The elevator makes the aircraft climb or dive. The ailerons produce rolling movement.

The aircraft must also be able to see and hear. Aircraft sensors are those devices, such as radars, direction finders and position plotters*, communication equipment, attitude gyros, air speed indicators and others, which enable the crew to know position, orientation and speed of aircraft.

* buoyancy – аэростатическая подъемная сила

* airfoil – аэродинамическая поверхность

* position plotter – прокладчик пути

Дата добавления: 2015-07-11