Friday, November 23, 2007

For the Red Hot Chilli Peppers song see Aeroplane (song).
A fixed-wing aircraft is a heavier-than-air craft where movement of the wings in relation to the aircraft is not used to generate lift. The term is used to distinguish from rotary-wing aircraft, or ornithopters, where the movement of the wing surfaces relative to the aircraft generates lift. Fixed-wing aircraft are called airplanes in North America (the U.S. and Canada), and aeroplanes in Commonwealth countries (other than Canada) and Ireland. These terms are derived from Greek αέρας (aéras-) ("air") and -plane. Both terms are often shortened to just planes.

A typical fixed-wing aircraft can be divided into the following major parts:

A long narrow often cylindrical form, called a fuselage, usually with tapered or rounded ends to make its shape aerodynamically smooth. The fuselage carries the human flight crew if the aircraft is piloted, the passengers if the aircraft is a passenger aircraft, other cargo or payload, and engines and/or fuel if the aircraft is so equipped. The pilots, who are members of the flight crew, operate the aircraft from a cockpit located at the front or top of the fuselage and equipped with windows, controls, and instruments. Passengers and cargo occupy the remaining available space in the fuselage. Some aircraft may have two fuselages, or additional pods or booms.
A wing (or wings in a multiplane) with an airfoil cross-section shape, used to generate aerodynamic lifting force to support the aircraft in flight by deflecting air downward as the aircraft moves forward. The wing halves are typically symmetrical about the plane of symmetry (for symmetrical aircraft), and are attached to the fuselage in different configurations depending on the aircraft design. The wing also stabilize the aircraft about its roll axis and the ailerons control rotation about that axis.
At least one control surface (or surfaces) mounted vertically usually above the rear of the fuselage, called a vertical stabilizer. The vertical stabilizer is used to stabilize the aircraft about its yaw axis (the axis in which the aircraft turns from side to side) and to control its rotation along that axis. Some aircraft have multiple vertical stabilizers, which can also be located on the wing in a highly swept wing configuration.
At least one horizontal surface at the front or back of the fuselage used to stabilize the aircraft about its pitch axis (the axis around which the aircraft tilts upward or downward). The horizontal stabilizer is usually mounted near the rear of the fuselage, or at the top of the vertical stabilizer, or sometimes a canard is mounted near the front of the fuselage for the same purpose.
On powered aircraft, one or more aircraft engines, are propulsion units that provide thrust to push the aircraft forward through the air. The engine is optional in the case of gliders that are not motor gliders. The most common propulsion units are propellers, powered by reciprocating or turbine engines, and jet engines, which provide thrust directly from the engine and usually also from a large fan mounted within the engine. When the number of engines is even, they are distributed symmetrically about the roll axis of the aircraft, which lies along the plane of symmetry (for symmetrical aircraft); when the number is odd, the odd engine is usually mounted along the centerline of the fuselage.
Landing gear, a set of wheels, skids, or floats (depending on the intended landing surface for the aircraft) that support the aircraft while it is on the surface. Aircraft parts
A number of fairly standardized controls allow pilots to direct aircraft in the air. The controls found in a typical fixed-wing aircraft are as follows:
Controls that are used in many aircraft, but are not as universal as the above, include:
Many aircraft also include controls that allow full or partial automation of flight, such as an autopilot, a wing leveler, or a flight management system. Pilots adjust these controls to select a specific attitude or mode of flight, and then the associated automation maintains that attitude or mode until the pilot disables the automation or changes the settings. In general, the larger and/or more complex the aircraft, the greater the amount of automation available to pilots.
Control duplication
More often than not, aircraft are designed so that either of two people (a pilot and copilot, for example) can fly the aircraft without changing seats. The most common arrangement is two complete sets of controls, one for each of two pilots sitting side by side, but in some aircraft (military fighter aircraft, some taildraggers and aerobatic aircraft) the dual sets of controls are arranged one in front of the other. A few of the less important controls may not be present in both positions, and one position is usually intended for the pilot in command (e.g., the left "captain's seat" in jet airliners). Some small aircraft use controls that can be moved from one position to another, such as a single yoke that can be swung into position in front of either the left-seat pilot or the right-seat pilot.
Aircraft that require more than one pilot usually have controls intended to suit each pilot position, but still with sufficient duplication so that all pilots can fly the aircraft alone in an emergency. For example, in jet airliners, the controls on the left (captain's) side include both the basic controls and those normally manipulated by the pilot in command, such as the tiller, whereas those of the right (first officer's) side include the basic controls again and those normally manipulated by the copilot, such as flap levers. The unduplicated controls that are required for flight are positioned so that they can be reached by either pilot, but they are often designed to be more convenient to the pilot who manipulates them under normal condition.

A yoke or joystick, which controls rotation of the aircraft about the pitch and roll axes. A yoke resembles a kind of steering wheel, and a control stick is just a simple rod with a handgrip. The pilot can pitch the aircraft downward by pushing on the yoke or stick, and pitch the aircraft upward by pulling on it. Rolling the aircraft is accomplished by turning the yoke in the direction of the desired roll, or by tilting the control stick in that direction. Pitch changes are used to adjust the altitude and speed of the aircraft; roll changes are used to make the aircraft turn. Control sticks and yokes are usually positioned between the pilot's legs; however, a sidestick is a type of control stick that is positioned on either side of the pilot (usually the left side for the pilot in the left seat, and vice versa, if there are two pilot seats).
Rudder pedals, which control rotation of the aircraft about the yaw axis. There are two pedals that pivot in such a way that pressing one forward moves the other backward, and vice versa. The pilot presses on the right rudder pedal to make the aircraft yaw to the right, and on the left pedal to make it yaw to the left. The rudder is used mainly to balance the aircraft in turns, or to compensate for winds or other effects that tend to turn the aircraft about the yaw axis.
A throttle, which adjusts the thrust produced by the aircraft's engines. The pilot uses the throttle to increase or decrease the speed of the aircraft, and to adjust the aircraft's altitude (higher speeds cause the aircraft to climb, lower speeds cause it to descend). In some aircraft the throttle is literally a single lever that controls thrust; in others, adjusting the throttle effectively means adjusting a number of different engine controls simultaneously in a coordinated way. Aircraft with multiple engines usually have individual throttle controls for each engine.
Brakes, used to slow and stop the aircraft on the ground, and sometimes for turns on the ground as well. In most aircraft the brakes are controlled by movable portions of the rudder pedals.
Flap levers, which are used to control the position of flaps on the wings.
Spoiler levers, which are used to control the position of spoilers on the wings, and to arm their automatic deployment in aircraft designed to deploy them upon landing.
Trim controls, which usually take the form of knobs or wheels and are used to adjust pitch, roll, or yaw trim.
A tiller, a small wheel or lever used to steer the aircraft on the ground (in conjunction with or instead of the rudder pedals).
A parking brake, used to prevent the aircraft from rolling when it is parked on the ground. Aircraft controls
Most aircraft have a large number of instruments that provide important information to the pilot. When these instruments are electronic, they are often called avionics. An aircraft that uses electronic displays almost exclusively is said to have a glass cockpit; mechanical instruments are sometimes referred to as steam gauges in comparison, even though they don't actually run on steam.
Basic instruments that are present in almost all aircraft include:
Most aircraft have many other instruments as well, including (but not limited to):

An airspeed indicator, which indicates the speed at which the aircraft is moving through the surrounding air.
An altimeter, which indicates the altitude of the aircraft above the ground or above mean sea level (MSL).
An attitude indicator, sometimes called an artificial horizon, which indicates the exact orientation of the aircraft about its pitch and roll axes.
A Turn coordinator, which helps the pilot maintain the aircraft in a coordinated attitude while turning.
A rate-of-climb indicator, which shows the rate at which the aircraft is climbing or descending
A horizontal situation indicator, existing in many different forms, all of which show the position and movement of the aircraft as seen from above with respect to the ground, including course/heading and other information.
Various instruments showing the status of each engine in the aircraft (operating speed, thrust, temperature, and other variables).
Combined display systems such as primary flight displays or navigation displays.
Information displays such as on-board weather radar displays. Aircraft instruments

Types of fixed-wing aircraft

Main article: Glider Gliders
Smaller and older propeller aircraft make use of reciprocating internal combustion engines that turns a propeller to create thrust. They are quieter than jet aircraft, but they fly at lower speeds, and have lower load capacity compared to similar sized jet powered aircraft. However, they are significantly cheaper and much more economical than jets, and are generally the best option for people who need to transport a few passengers and/or small amounts of cargo. They are also the aircraft of choice for pilots who wish to own an aircraft.
Turboprop aircraft are a halfway point between propeller and jet: they use a turbine engine similar to a jet to turn propellers. These aircraft are popular with commuter and regional airlines, as they tend to be more economical on shorter journeys.

Airplane Propeller aircraft

Main article: Jet aircraft Jet aircraft

Main article: Rocket-powered aircraft Rocket-powered aircraft
Ramjet aircraft are mostly in the experimental stage. The D-21 Tagboard was an unmanned Mach 3+ reconnaissance drone that was put into production in 1969 for spying, but due to the development of better spy satellites, it was cancelled in 1971. The SR-71's Pratt & Whitney J58 engines ran 80% as ramjets at high-speeds (Mach 3.2). The SR-71 was dropped in the early 70's and then brought back during the cold war. They were used also in the Gulf War. The last SR-71 flight was in October 2001.

Ramjet aircraft
Scramjet aircraft are in the experimental stage. The Boeing X-43 is an experimental scramjet with a world speed record for a jet-powered aircraft - Mach 9.6, nearly 12,000 km/h (≈ 7,000 mph) at an altitude of about 36,000 meters (≈ 110,000 ft). The X-43A set the flight speed record on 16 November 2004.

Scramjet aircraft

Main articles: Aviation history and First flying machine Designing and constructing an aircraft
There are few companies that produce aircraft on a large scale. However, the production of an aircraft for one company is a process that actually involves dozens, or even hundreds, of other companies and plants, that produce the parts that go into the aircraft. For example, one company can be responsible for the production of the landing gear, while another one is responsible for the radar. The production of such parts is not limited to the same city or country; in the case of large aircraft manufacturing companies, such parts can come from all over of the world.
The parts are sent to the main plant of the aircraft company, where the production line is located. In the case of large aircraft, production lines dedicated to the assembly of certain parts of the aircraft can exist, especially the wings and the fuselage.
When complete, an aircraft goes through a set of rigorous inspection, to search for imperfections and defects, and after being approved by the inspectors, the aircraft is tested by a pilot, in a flight test, in order to assure that the controls of the aircraft are working properly. With this final test, the aircraft is ready to receive the "final touchups" (internal configuration, painting, etc), and is then ready for the customer.

Industrialized production

Main article: Air safety Safety

Main article: Aviation and climate change See also

Blatner, David. The Flying Book : Everything You've Ever Wondered About Flying On Airplanes. ISBN 0-8027-7691-4

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