Airplane

An airplane is an aircraft designed to fly through the atmosphere using wings to generate lift and one or more engines to provide thrust. Most modern airplanes are heavier than air and remain airborne because their wings create an upward aerodynamic force as air flows around them. The fuselage contains the cockpit, passengers or cargo, while the wings usually contain fuel tanks and support the main lifting surfaces. At the rear, the horizontal and vertical tail surfaces help control the aircraft's pitch and direction.

Flight controls such as ailerons, elevators and the rudder allow the pilot or flight-control system to change the airplane's attitude and path. Airplanes can have different configurations and propulsion systems. Passenger aircraft commonly use turbofan engines, while smaller aircraft may use piston engines or turboprops. The shape of the wings and body is carefully designed to reduce drag and improve efficiency. During a typical flight, the airplane first accelerates along a runway until the wings generate enough lift for takeoff.

Once airborne, the engines provide thrust to overcome aerodynamic drag, while the wings produce the lift needed to maintain altitude. Pilots and onboard systems constantly monitor speed, altitude, direction and engine performance. Modern airliners use sophisticated computers and navigation equipment, but pilots remain responsible for controlling the aircraft and making operational decisions. When approaching an airport, the airplane descends and reduces speed before landing on a runway.

Brakes, spoilers and sometimes reverse thrust help slow it after touchdown. Air travel makes it possible to cross very large distances in relatively little time and is used for passenger transport, freight, emergency services, research and many other purposes. Although airplanes operate at high speeds and altitudes, their design, maintenance and operation are governed by strict safety standards.