Aircraft




Aeroplanes


Military jets
A military jet fighter is designed for high speed and manoeuvrability in the air. It may be used to combat other jet fighters or to intercept enemy bombers and attack them with guns or missiles. It can also be used to attack targets on the ground. It can fly at supersonic speeds: faster than the speed of sound. On some jet fighters the angle of their wings can be altered (“swept back”) in mid-flight so the plane can go even faster.

Inside a jet fighterThe fighter’s nose contains both the cockpit, where the pilot or pilots sit, and the plane’s electronics. These include radar, used to detect enemy targets, as well as devices designed to shield the plane from enemy radar.


Light aircraft
A light aircraft is often used for recreation or for teaching pilots to fly. Together with fuel and passengers, the Cessna Skyhawk weighs around 1150 kilograms (2535 lb). It cruises at around 230 km/h (140 mph). The small piston engine drives a propeller. The pilot steers the plane using a control column and rudder pedals, which are connected to the plane’s control surfaces.
Very light jets
Not all jets are huge airliners or military aircraft. The very light jet is designed for use as an air taxi service, normally making journeys of up to 800 kilometres (500 miles). It measures around 10 metres (33 feet) in length, with a wingspan of 11 metres (36 feet). It stands just 3.4 metres (11 feet) high off the runway. Powered by two small jet engines, it is a six-seater that can be flown by a single pilot. The plane is equipped with the latest technology.
Fuel is contained in the wings of the plane. The hollow interior of each wing serves as the fuel tank. This is called a “wet wing” fuel tank. Refuelling ports are in each wingtip. Electric pumps control the flow of fuel to each engine. Inside, the pilot uses the side stick and rudder pedals to steer. These are linked to a computer, which sends electronic signals to electric motors, called actuators. The actuators move the control surfaces: the elevators on the tailplane, the ailerons on the wings and the rudder on the tailfin.
A Magellan Eclipse 500 in cutaway


The plane is fitted with powerful computers, making up what is called a Total Aircraft Integration System, or fly-by-wire. It acts almost like a co-pilot, a “brain” that runs every system—including navigation, steering and air conditioning—in the plane automatically.
Microlights
Very small, low-speed, powered aeroplanes are called microlights, or ultralight aircraft. With a maximum take-off weight—in Europe—of 450 kilograms (990 lb), they have fixed wings. They are steered like standard aeroplanes, by pitching, yawing or rolling.
Helicopters
Helicopters can fly backwards or sideways as well as forwards, hover in mid-air and take off or land vertically. They do not need the runway that aeroplanes must have for take-off or landing. Because of this, helicopters are very useful for rescuing people in mountains or out at sea. They can also transport people to and from oil rigs or the tops of skyscrapers in cities.
All helicopters have rotor blades shaped like long, thin wings. They rotate very quickly. The main rotor provides lift and propels the aircraft through the air. The tail rotor stops the helicopter’s fuselage from spinning in the opposite direction to the main rotor.
All helicopters have rotor blades shaped like long, thin wings. They rotate very quickly. The main rotor provides lift and propels the aircraft through the air. The tail rotor stops the helicopter’s fuselage from spinning in the opposite direction to the main rotor.
Gliders are aeroplanes that fly without the use of engines. They climb by using rising air currents. They have rigid wings and an undercarriage. Some have engines fitted which can be used for take-off and making a flight last longer. Gliders are designed to minimize drag and so have very long, thin wings and a narrow cockpit. They are able to glide for long distances at high speed with a minimum loss of height.
Hang gliders
Hang gliders are small gliders, launched by foot from high ground or towed into the air. They have a flexible, fabric wing fixed to a light aluminium alloy frame. The pilot is attached to a harness suspended from the frame. He or she controls the aircraft by shifting their body weight.
Hot-air balloon


Dirigibles and airships
A powered, steerable balloon is called a dirigible. It is filled with lighter-than-air gas. A dirigible with a flexible envelope is known as a blimp. An airship is a large dirigible with a rigid outer framework. Its long, streamlined hull is filled with lighter-than-air gases such as helium. It is powered by engines and steered by a rudder. Airships were used for passenger flights until the 1940s.
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