The Cessna 172 Skyhawk is the most produced aircraft in history. An aircraft is a machine that is able to fly by gaining support from the air. The aircraft brake system pdf activity that surrounds aircraft is called aviation.
Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Each of the two World Wars led to great technical advances. Pioneers of flight, from the earliest experiments to 1914. First World War, 1914 to 1918.
Aviation between the World Wars, 1918 to 1939. Second World War, 1939 to 1945. Postwar era, also called the jet age, 1945 to the present day. Aerostats use buoyancy to float in the air in much the same way that ships float on the water. A powered, steerable aerostat is called a dirigible.
Non-rigid dirigibles are characterized by a moderately aerodynamic gasbag with stabilizing fins at the back. This dynamic movement through the air is the origin of the term aerodyne. Aerodynamic lift involving wings is the most common, with fixed-wing aircraft being kept in the air by the forward movement of wings, and rotorcraft by spinning wing-shaped rotors sometimes called rotary wings. A wing is a flat, horizontal surface, usually shaped in cross-section as an aerofoil.
With powered lift, the aircraft directs its engine thrust vertically downward. Rocket-powered missiles that obtain aerodynamic lift at very high speed due to airflow over their bodies are a marginal case. The forerunner of the fixed-wing aircraft is the kite. Whereas a fixed-wing aircraft relies on its forward speed to create airflow over the wings, a kite is tethered to the ground and relies on the wind blowing over its wings to provide lift. The first heavier-than-air craft capable of controlled free-flight were gliders. A glider designed by George Cayley carried out the first true manned, controlled flight in 1853. Besides the method of propulsion, fixed-wing aircraft are in general characterized by their wing configuration.
Braced or cantilever, rigid, or flexible. Location of the horizontal stabilizer, if any. A variable geometry aircraft can change its wing configuration during flight. A flying wing has no fuselage, though it may have small blisters or pods. The opposite of this is a lifting body, which has no wings, though it may have small stabilizing and control surfaces. Wing-in-ground-effect vehicles are not considered aircraft.