See R. Allen, Major Airports of the World (1979), R. Horonjeff, Planning and Design of Airports (1983), and A. T. Wells, Airport Planning and Management (1986).
An airport is a location where aircraft such as airplanes, helicopters, and blimps take off and land. Aircraft may also be stored or maintained at an airport. An airport consists of at least one surface such as a runway, a helipad, or water for takeoffs and landings, and often includes buildings such as hangars and terminal buildings.
Larger airports may have fixed base operator services, seaplane docks and ramps, air traffic control, passenger facilities such as restaurants and lounges, and emergency services. A military airport is known as an airbase or air station. The terms airfield, airstrip, and aerodrome may also be used to refer to airports, and the terms heliport, seaplane base, and STOLport refer to airports dedicated exclusively to helicopters, seaplanes, or short takeoff and landing aircraft. In some jurisdictions, the term airport is used where the facility is licensed as such by the relevant government organization (e.g. Federal Aviation Administration (FAA), Transport Canada). Elsewhere the distinction is merely one of general appearance. Yet other areas define an airport by its having the necessary customs offices etc expected of a port, though the more general term is airport of entry.
Smaller or less-developed airports — which represent the vast majority — often have a single runway shorter than 1,000 m (3,300 ft). Larger airports for airline flights generally have paved runways 2,000 m (6,600 ft) or longer. Many small airports have dirt, grass, or gravel runways, rather than asphalt or concrete.
In the United States, the minimum dimensions for dry, hard landing fields are defined by the FAR Landing And Takeoff Field Lengths. These include considerations for safety margins during landing and takeoff. Heavier aircraft require longer runways.
The longest public-use runway in the world is at Qamdo Bangda Airport in China. It has a length of 5,500 m (18,045 ft). The world's widest paved runway is at Ulyanovsk Vostochny Airport in Russia and is 105 m (344 ft) wide.
As of 2006, there were approximately 49,000 airports around the world, including 14,858 in the US., the U.S. having the most in the world
Most of the world's airports are owned by local, regional, or national government bodies who then lease the airport to private corporations who oversee the airport's operation. For example, BAA Limited (BAA) operates seven of the commercial airports in the United Kingdom, as well as several other airports outside of the UK. Germany's Frankfurt Airport is managed by the quasi-private firm Fraport.
In the US and Canada, commercial airports are generally operated directly by government entities or government-created airport authorities (also known as port authorities).
Many US airports still lease part or all of their facilities to outside firms, who operate functions such as retail management and parking. In the US, all commercial airport runways are certified by the FAA, but maintained by the local airport under the regulatory authority of the FAA.
Despite the reluctance to privatize airports in the US (despite the FAA sponsoring a privatization program since 1996), the government-owned, contractor-operated (GOCO) arrangement is the standard for the operation of commercial airports in the rest of the world.
In New Zealand, Auckland International Airport, the nation's main international airport, is fully privatised. Ownership and operation of the 1,497 hectare complex is vested entirely with Auckland International Airport Limited, a public company, with the only governmental involvement being Airways Corporation of New Zealand's operation of air traffic control systems. Similar arrangements pertain to Wellington and Christchurch airports, and most other main airports are operated by private companies.
In Argentina, 32 airports including the main airport Ministro Pistarini International Airport are operated by Aeropuertos Argentina 2000, a private company. On the other hand, 3 airports are operated by another company named London Supply.
Airports are divided into landside and airside areas. Landside areas include parking lots, public transportation train stations, tank farms and access roads. Airside areas include all areas accessible to aircraft, including runways, taxiways, ramps and tank farms. Access from landside areas to airside areas is tightly controlled at most airports. Passengers on commercial flights access airside areas through terminals, where they can purchase tickets, clear security, check or claim luggage and board aircraft through gates. The waiting areas which provide passenger access to aircraft are typically called concourses, although this term is often used interchangeably with terminal.
The area where aircraft park next to a terminal to load passengers and baggage is known as a ramp (or "the tarmac"). Parking areas for aircraft away from terminals are called aprons.
Airports can be towered or non-towered, depending on air traffic density and available funds. Due to their high capacity and busy airspace, many international airports have air traffic control located on site.
Airports with international flights have customs and immigration facilities. However, as some countries have agreements that allow travel between them without customs and immigrations, such facilities are not a definitive need for an international airport. International flights often require a higher level of physical security, although in recent years, many countries have adopted the same level of security for international and domestic travel.
The prices charged for food are generally higher than are available elsewhere in the region. However, some airports, such as John F. Kennedy International Airport's Terminal 8, have no restaurants at all. Airport fees are fees paid for use of services of airports, such as in the Subic Bay International Airport. However, some airports now regulate food costs to keep them comparable to "street prices". This term is misleading as prices often match the manufacturer's suggested retail price (MSRP) but are almost never discounted.
Some airport restaurants offer regional cuisine specialties for those in transit so that they may sample local culture in some small way without leaving the airport.
These services are usually reserved for First and Business class passengers, premium frequent flyers, and members of the airlines clubs, however each airline has its own set of rules as to what constitutes a premium passenger and what additional services and benefits are offered.
Premium services may sometimes be open to passengers who are members of a different airlines frequent flyer program. This can sometimes be part of a reciprocal deal, usually due to both airlines been part of the same alliance, or as a ploy to attract premium customers away from rival airlines.
Sometimes these premium services will be offered to a non premium passenger if the airline has made a mistake in handling of the passenger, for instance the passenger is unduly delay, or has their baggage mishandled. However this is up to the discretion of the operating airline.
Airline lounges may include free or reduced rate food, both non alcoholic drinks and alcoholic drinks. Lounges themselves typically have better seating, showers, quite areas, TV’s, computer and internet access, as well as power points which passengers are permitted to use to power laptops or other electronic devices. They will also sometimes employ barista’s, bar persons and high quality chefs.
A certain lounges may restrict the services it provides depending on the time of day, for example they may not serve alcoholic drinks before a certain time of day. They may also only serve certain foods such as breakfast cereals only at certain times of the day.
Airlines sometimes operate multiple lounges within the one airport terminal allowing ultra premium customers, such as first class customers, additional services, which are not available to other premium customers.
Some airports, typically military airbases, have long runways used as emergency landing sites. Many airbases have arresting equipment for fast aircraft, known as arresting gear – a strong cable suspended just above the runway and attached to a hydraulic reduction gear mechanism. Together with the landing aircraft's arresting hook, it is used in situations where the brakes would have little or no effect.
The earliest airplane takeoff and landing sites were grassy fields. The plane could approach at any angle that provided a favorable wind direction. A slight improvement was the dirt-only field, which eliminated the drag from grass. However, these only functioned well in dry conditions. They would eventually be replaced by concrete surfaces that allowed all-weather landings in daylight and at night.
The title of "world's oldest airport" is disputed, but College Park Airport in Maryland, US, established in 1909 by Wilbur Wright, is generally agreed to be the world's oldest continually operating airfield, although it serves only general aviation traffic.
Bremen Airport opened in 1913 and remains in use, although it served as an American military field between 1945 and 1949. Amsterdam Schiphol Airport opened on September 16, 1916 as a military airfield, but only accepted civil aircraft from December 17, 1920, allowing Sydney Airport in Sydney, Australia—which started operations in January 1920—to claim to be one of the world's oldest continually operating commercial airport..
Increased aircraft traffic during World War I led to the construction of landing fields. Airplanes had to approach these from certain directions and this led to the development of aids for directing the approach and landing slope.
Following the war, some of these military airfields added commercial facilities for handling passenger traffic. One of the earliest such fields was Paris - Le Bourget Airport at Le Bourget, near Paris. The first international airport to open was the Croydon Airport, in South London, although an airport at Hounslow had been temporarily operating as such for nine months. In 1922, the first permanent airport and commercial terminal solely for commercial aviation was built at Königsberg, Germany. The airports of this era used a paved "apron", which permitted night flying as well as landing heavier airplanes. The first lighting used on an airport was during the later part of the 1920s; in the 1930s approach lighting came into use. These indicated the proper direction and angle of descent. The colors and flash intervals of these lights became standardized under the International Civil Aviation Organization (ICAO). In the 1940s, the slope-line approach system was introduced. This consisted of two rows of lights that formed a funnel indicating an aircraft's position on the glideslope. Additional lights indicated incorrect altitude and direction.
Following World War II, airport design became more sophisticated. Passenger buildings were being grouped together in an island, with runways arranged in groups about the terminal. This arrangement permitted expansion of the facilities. But it also meant that passengers had to travel further to reach their plane.
An improvement in the landing field was the introduction of grooves in the concrete surface. These ran perpendicular to the direction of the landing aircraft and served to draw off excess water in rainy conditions that could build up in front of the plane's wheels.
Airport construction boomed during the 1960s with the increase in jet aircraft traffic. Runways were extended out to 3 km (9,800 ft). The fields were constructed out of reinforced concrete using a slip-form machine that produces a continual slab with no disruptions along the length.
Modern runways are thickest in the area where airplanes move slowly and are expected to have maximum load, i.e. runway ends. A common myth is that airplanes produce their greatest load during landing due to the "impact" of landing. This is untrue as much of the aircraft weight remains on the wings due to lift. Runways are constructed as smooth and level as possible.
The name of the airport itself can be its location, such as Hong Kong International Airport. It can be the name of a celebrity, commonly a politician, e.g. Ninoy Aquino International Airport, Indira Gandhi International Airport, Atatürk International Airport, Toronto Pearson International Airport, Montréal-Pierre Elliott Trudeau International Airport or Charles de Gaulle International Airport. Airports may also be named after a person associated with the region it serves or prominent figures in aviation history, such as Will Rogers World Airport, Liverpool John Lennon Airport, Imam Khomeini International Airport, or more recently Belfast City Airport was renamed George Best Belfast City Airport in memory of the football star who was born in Northern Ireland.
Airport names may include the word "International" reflecting their ability to handle international aviation traffic, although the airport may not actually operate any such flights, such as Texel International Airport. Some airports with international immigration facilities may also choose to drop the word from their airport names (eg. Perth Airport, Singapore Changi Airport).
Airport security normally requires baggage checks, metal screenings of individual persons, and rules against any object that could be used as a weapon. Since the September 11, 2001 attacks, airport security has been dramatically increased.
The majority of the world's airports are non-towered, with no air traffic control presence. However, at particularly busy airports, or airports with other special requirements, there is an air traffic control (ATC) system whereby controllers (usually ground-based) direct aircraft movements via radio or other communications links. This coordinated oversight facilitates safety and speed in complex operations where traffic moves in all three dimensions. Air traffic control responsibilities at airports are usually divided into at least two main areas: ground and tower, though a single controller may work both stations. The busiest airports also have clearance delivery, apron control, and other specialized ATC stations.
Ground Control is responsible for directing all ground traffic in designated "movement areas", except the traffic on runways. This includes planes, baggage trains, snowplows, grass cutters, fuel trucks, and a wide array of other vehicles. Ground Control will instruct these vehicles on which taxiways to use, which runway they will use (in the case of planes), where they will park, and when it is safe to cross runways. When a plane is ready to take off it will stop short of the runway, at which point it will be turned over to Tower Control. After a plane has landed, it will depart the runway and be returned to Ground Control.
Tower Control controls aircraft on the runway and in the controlled airspace immediately surrounding the airport. Tower controllers may use radar to locate an aircraft's position in three-dimensional space, or they may rely on pilot position reports and visual observation. They coordinate the sequencing of aircraft in the traffic pattern and direct aircraft on how to safely join and leave the circuit. Aircraft which are only passing through the airspace must also contact Tower Control in order to be sure that they remain clear of other traffic.
At extremely large airports, a circuit is in place but not usually used. Rather, aircraft (usually only commercial with long routes) request approach clearance while they are still hours away from the airport, often before they even take off from their departure point. Large airports have a frequency called Clearance Delivery which is used by departing aircraft specifically for this purpose. This then allows airplanes to take the most direct approach path to the runway and land without worrying about interference from other aircraft. While this system keeps the airspace free and is simpler for pilots, it requires detailed knowledge of how aircraft are planning to use the airport ahead of time and is therefore only possible with large commercial airliners on pre-scheduled flights. The system has recently become so advanced that controllers can predict whether an aircraft will be delayed on landing before it even takes off; that aircraft can then be delayed on the ground, rather than wasting expensive fuel waiting in the air.
There are a number of aids available to pilots, though not all airports are equipped with them. A Visual Approach Slope Indicator (VASI) helps pilots fly the approach for landing. Some airports are equipped with a VHF omnidirectional range (VOR) to help pilots find the direction to the airport. VORs are often accompanied by a distance measuring equipment (DME) to determine the distance to the VOR. VORs are also located off airports, where they serve to provide airways for aircraft to navigate upon. In poor weather, pilots will use an instrument landing system (ILS) to find the runway and fly the correct approach, even if they cannot see the ground. The number of instrument approaches based on the use of the Global Positioning System (GPS) is rapidly increasing and may eventually be the primary means for instrument landings.
Larger airports sometimes offer precision approach radar (PAR), but these systems are more common at military air bases than civilian airports. The aircraft's horizontal and vertical movement is tracked via radar, and the controller tells the pilot his position relative to the approach slope. Once the pilots can see the runway lights, they may continue with a visual landing.
There are two classes of signage at airports, with several types of each:
On runways, green lights indicate the beginning of the runway for landing, while red lights indicate the end of the runway. Runway edge lighting consists of white lights spaced out on both sides of the runway, indicating the edge. Some airports have more complicated lighting on the runways including lights that run down the centerline of the runway and lights that help indicate the approach (an Approach Lighting System, or ALS). Low-traffic airports may use Pilot Controlled Lighting to save electricity and staffing costs.
Along taxiways, blue lights indicate the taxiway's edge, and some airports have embedded green lights that indicate the centerline.
Planes take-off and land into the wind in order to achieve maximum performance. Because pilots need instantaneous information during landing, a windsock is also kept in view of the runway.
Hazards to aircraft include debris, nesting birds, and reduced friction levels due to environmental conditions such as ice, snow, or rain. Part of runway maintenance is airfield rubber removal which helps maintain friction levels. The fields must be kept clear of debris using cleaning equipment so that loose material does not become a projectile and enter an engine duct (see foreign object damage). In adverse weather conditions, ice and snow clearing equipment can be used to improve traction on the landing strip. For waiting aircraft, equipment is used to spray special deicing fluids on the wings.
Many airports are built near open fields or wetlands. These tend to attract bird populations, which can pose a hazard to aircraft in the form of bird strikes. Airport crews often need to discourage birds from taking up residence.
Some airports are located next to parks, golf courses, or other low-density uses of land. Other airports are located near densely-populated urban or suburban areas. In the 1980s, a conflict arose in San Jose, California, when a plane attempting to land at Reid-Hillview Airport (built in the 1930s) collided with a Macy's department store at the Eastridge Center. Many local residents tried to get the airport shut down, even though it had been there for fifty years: their neighborhoods (and the mall) were about a decade old.
An airport can have areas where collisions between airplanes on the ground tend to occur. Records are kept of any incursions where airplanes or vehicles are in an inappropriate location, allowing these "hot spots" to be identified. These locations then undergo special attention by transportation authorities (such as the FAA in the US) and airport administrators.
During the 1980s, a phenomenon known as microburst became a growing concern due to accidents caused by microburst wind shear. (For example, see Delta Air Lines Flight 191.) Microburst radar was developed as an aid to safety during landing, giving two to five minutes warning to aircraft in the vicinity of the field of a microburst event.
Some airfields now have a special surface known as soft concrete at the end of the runway that behaves somewhat like styrofoam, bringing the plane to a relatively rapid halt as the material disintegrates. These surfaces are useful when the runway is located next to a body of water or other hazard, and prevent the planes from overrunning the end of the field.
Most airports have ground crew handling the loading and unloading of passengers, crew, baggage and other services. Some ground crew are linked to specific airlines operating at the airport.
The construction of new airports, or addition of runways to existing airports, is often resisted by local residents because of the effect on the countryside, historical sites, local flora and fauna. Due to the risk of collision between birds and airplanes, large airports undertake population control programs where they frighten or shoot birds.
The construction of airports has been known to change local weather patterns. For example, because they often flatten out large areas, they can be susceptible to fog in areas where fog rarely forms. In addition, because they generally replace trees and grass with pavement, they often change drainage patterns in agricultural areas, leading to more flooding, run-off and erosion in the surrounding land.
Some of the airport administrations prepare and publish annual environmental reports in order to show how they consider these environmental concerns in airport management issues and how they protect environment from airport operations. These reports contains all environmental protection measures performed by airport administration in terms of water, air, soil and noise pollution, resource conservation and protection of natural life around the airport.
An airbase, sometimes referred to as a military airport or airfield, provides basing and support of military aircraft. Some airbases provide facilities similar to their civilian counterparts. For example, RAF Brize Norton in Oxfordshire, England has a terminal which caters to passengers for the Royal Air Force's scheduled Tristar flights to the Falkland Islands. Military airbases may also be co-located with civilian airports, sharing the same tower/air traffic control facilities, runways, taxiways and emergency services, but with separate terminals, parking areas, hangars and shelter areas. Examples of this are Bardufoss Airport/Bardufoss Air Station and Gardermoen Airport/Gardermoen Air Station, both in Norway. A special variant of a military airfield is the aircraft carrier.
An aircraft carrier is a warship that functions as a floating airport for military aircraft. Aircraft carriers allow a naval force to project air power great distances without having to depend on local bases for land-based aircraft. After their development in World War I, aircraft carriers replaced the battleship as the centrepiece of a modern fleet during World War II. Unescorted carriers are considered vulnerable to missile or submarine attacks and therefore travel as part of a carrier battle group that includes a wide array of other ships with specific functions.
Several computer simulation games put the player in charge of an airport. These include Airport Tycoon and the sequels; Airport Tycoon 2 and Airport Tycoon 3. There is also a Japanese series of games called Air Traffic Controller.