thumb|Europeisk lufttrafik 1924

'''Flygplats''' kallas plats där flygplan startar och landar. Benämningen flygplats används oftare inom civil luftfart än inom militär dito. Inom det senare används istället det specifika ordet ''flygbas'' eller det mer allmängiltiga ordet ''flygfält''. Jämför även flygflottilj. När en flygflottilj delar flygfält med en civil flygplats preciseras ibland den civila delen som '''flygstation'''. Idag finns detta bara på två flygplatser i Sverige, Ronneby och Luleå. Totalt finns ca 200 flygplatser i Sverige. Dessutom finns många privata landningsplatser som inte är officiellt tillkännagivna.

thumb|[[Incheon, en flygplats i Sydkorea.]]

==En flygplats utrustning==
Varje flygplats har minst en embarkeringsbrygga'', även kallad ''finger'', som dockar med flygplanet. Plattan förbinds med rullbanorna via taxibanor. De största flygplatserna har flera terminaler som har varsin uppsättning av incheckningsområde, utgångar, butiker, säkerhetskontroll med mera, medan mindre flygplatser endast har en terminal. Flygplatser (flygfält) utan passagerartrafik har ofta endast hangarer och till exempel flygklubbslokaler eller kan helt och hållet sakna byggnader.

Flygplatser indelas i instrumentflygplatser och icke-instrumentflygplatser. För att flygplanen som trafikerar instrumentflygplatser ska kunna landa i dåligt väder krävs att där finns instrumentinflygningshjälpmedel. Det vanligaste systemet idag är ILS (Instrument Landing System). ILS:en består i huvudsak utav tre olika delar. Först har vi lokalisatorn (Localizer) som är en antenn som sänder ut radiovågor i banans riktning för att på så vis ge flygplanen en indikation på hur de ligger till i sidled i förhållande till banan. Vidare har vi en så kallad glidbana (Glideslope) som är en antenn placerad intill flygplanens landningspunkt på banan. Denna sänder ut en radiostråle som skall ge flygplanen information om hur de ligger till i höjdled i förhållande till en bestämd glidbana (normalt cirka 3 grader). Sista delen av ILS-systemet är så kallade fyrar (Markers) som sitter längs bestämda avstånd från banan och sänder ut ljudsignaler i flygplanet, och ger information om hur långt ut från banan flygplanet befinner sig. Fyrarna kan dock ersättas med en DME (Distance Measuring Equipment), som är en sorts radiofyr som kontinuerligt sänder ut flygplanets avstånd från antennen. Inflygningen genomförs till en viss höjd och om piloterna då inte ser banan måste de avbryta landningen och stiga upp igen. På icke-instrumentflygplatser landar man alltid i "bra" väder men man kan genomföra starter i ned till 600 meters sikt.   

Internationella flygplatser är av säkerhetsskäl och bekvämlighetsskäl inbyggda, d.v.s. att de flesta passagerare går inomhus från att de anländer till flygplatsen tills de sitter på flygplanet (undantaget då planen inte kopplas till en brygga utan stannar på plattan, man har dock koll på passagerarna ändå). Internationella flygplatser måste hålla kontroll över passagerarströmmar med hjälp av rörelsefrihetsbegränsande anordningar (väggar, vändkors m.m.). De personer som passerat boardingkontrollen får till exempel inte gå bakåt i systemet och inte heller sammanblandas med andra passagerare, för att ingen ska kunna skicka en väska utan att åka själv. Dessutom måste utrikes anländande hållas separerade tills de passerat passkontrollen.

En av anledningarna till utbyggnaden av pir F på Schengenområden från resande från/till platser utanför Schengenområdet, så att endast de sistnämnda passerar passkontrollen.

De allra största flygplatserna har ofta mycket goda kommunikationer med omvärlden. Till dessa brukar någon motorväg ansluta direkt till flygplatsen och många av dessa har även en järnvägsstation. Exempel på flygplatser med detta är Arlanda och Kastrup.

Mindre flygplatser drivs ofta i kommunal eller privat regi. På de flesta av dessa finns en flygklubb som genomför flygutbildning och vars medlemmar delar på flygplansägandet.

==Flygplatskoder==
Större flygplatser betecknas med en trebokstavig flygplatskod som utfärdats av internationella lufttransportsförbundet (IATA). Bokstäverna i koden väljs så de anknyter till flygplatsens namn, men brist på lediga beteckningar resulterar ibland i konstiga beteckningar som MXX för Mora flygplats. Dessa koder används mest för biljetter och bagage. 

Det finns även fyrabokstavskoder för flygplatser som utfärdas av internationella civilluftfartsorganisationen (ICAO). Dessa har en logisk geografisk uppbyggnad där till exempel alla flygplatser i Nordeuropa börjar med bokstaven E och alla svenska med bokstäverna ES. Tyvärr är de inte mer lättbegripliga för den oinvigde, till exempel ESMQ för Kalmar flygplats. De används av piloter och flygledare mm.

==Ett urval av flygplatser i Sverige== 
*Stockholm-Arlanda flygplats
*Stockholm-Bromma flygplats
*Stockholm-Västerås flygplats
*Dala Airport Borlänge
*Göteborg City Airport f.d. Säve 
*Göteborg-Landvetter flygplats 
*Åre Östersund Airport
*Halmstad flygplats
*Jönköping flygplats
*Kalmar Airport
*Kiruna flygplats
*Kristianstad Airport 
*Luleå Airport - Kallax 
*Norrköping flygplats 
*Malmö-Sturup flygplats
*Umeå flygplats
*Örebro flygplats
*Midlanda
*Ängelholm-Helsingborgs flygplats

thumb|right|The passenger terminal buildings at [[Incheon International Airport, Incheon, South Korea, considered a large airport.]]
thumb|[[Barra Airport (Scotland)|Barra Airport, Outer Hebrides, Scotland, the world's only airport using a beach runway for scheduled services.]]
thumb|right|[[Paraparaumu Airport, a small-sized airfield/airport]]
thumb|right|[[JetBlue Airways at Santiago, DR.]]

An '''airport''' is a facility where airplanes, 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 terminal buildings.

Larger airports may have a variety of facilities and infrastructure, including fixed base operator services, 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 air''port'' by its having the necessary customs offices etc expected of a port, though the more general term is airport of entry.

==Attributes==
thumb|The international [[public domain symbol for air transportation, created by AIGA.]]

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 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<ref>[https://www.cia.gov/library/publications/the-world-factbook/fields/2053.html CIA World Factbook]</ref>

===Airport ownership and operation===
thumbnail|right|[[Rio de Janeiro-Galeão International Airport.]]
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).

thumb|[[Frankfurt Airport is managed by Fraport]]

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 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.

===Airport structures===
thumb|A terminal at Hyderabad International Airport
thumb|A terminal at Chhatrapati Shivaji International Airport

Airports are divided into ''landside'' and ''airside'' areas. Landside areas include tank farms and access 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, to the media and uninitiated, "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.

Modern engineers and architects are developing "floating airports" which could be located several miles at sea and which would use designs such as pneumatic stabilized platform technology.

=== Shops and food services ===
thumb|right|Duty free shopping area at [[Ben Gurion International Airport in Tel Aviv, Israel]]
thumb|right|Food court and shops, [[Halifax International Airport]]

Airports have a captive audience, and consequently 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 so-called "street prices".  This term is misleading as prices often match the manufacturer's suggested retail price (MSRP) but are almost never discounted.

=== Premium and VIP services ===
Several mid-large size airports also have facilities for premium passengers. In the US, these lounges are typically for international or long-haul first and frequent fliers on long haul flights (regardless of what class they are in). In the rest of the world, the lounges are not open to purchase, but can be used by all premium passengers and most elite frequent fliers. Some lounges are comparatively spartan and only offer a quiet place to sit and work; other lounges include meals and massage services.

===Cargo and freight services===
In addition to people, airports are responsible for moving large volumes of cargo around the clock. Cargo airlines often have their own on-site and adjacent infrastructure to rapidly transfer parcels between ground and air modes of transportation.

===Support services===
Aircraft maintenance, pilot services, aircraft rental, and hangar rental are most often performed by a fixed base operator (FBO). At major airports, particularly those used as hubs, airlines may operate their own support facilities.
thumb|International [[Airport terminal|terminal, Hall 1 and Hall 1, at Houari Boumedienne Airport, Algiers, Algeria]]
Some airports, typically military airbases, have long runways used as emergency landing sites. Many airbases have arresting equipment for fast aircraft, known as 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.

=== Airport access ===
Many large airports in the world are located next to or even above railway trunk routes, for instance Frankfurt Airport, New York and the Silver Line T at Boston's Logan International Airport by the Massachusetts Bay Transportation Authority (MBTA). These systems are usually directly connected to the main terminals. Large airports usually have access also through freeways from which cars fed into two access roads, designed as loops, one sitting on top of the other. One level is for departing passengers and the other is for arrivals. This road concept was pioneered at Los Angeles International Airport.  

=== Internal transport ===
The distances passengers need to move within a large airport can be substantial.  It is common for airports to provide moving walkways and buses.  The Hartsfield-Jackson Atlanta International Airport has a tram that takes people through the Concourses and Baggage Claim.

==History and development==
thumbnail|Qantas [[Avro 504|AVRO 504K replica, first plane flown by Qantas, Sydney Airport]]
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 Wilbur Wright, is generally agreed to be the world's oldest continually operating airfield<ref>[http://www.pgparks.com/places/historic/cpairport.html College Park Airport]</ref>, although it serves only general aviation traffic.

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.<ref>[http://www.sydneyairport.com.au/NR/rdonlyres/353DC91E-A259-449B-8B68-C8E88CB58691/0/FactSheetHistory1.pdf Airport history]</ref>.

The first known usage of the term "airport" appeared in a newspaper article in 1919, in reference to Bader Field in Atlantic City, New Jersey.<ref>[http://www.pressofatlanticcity.com/news/newjersey/story/6787513p-6655816c.html Atlantic City airport, where 'air-port' coined, closing]</ref>

Increased aircraft traffic during World War I led to the construction of regular landing fields. Airplanes had to approach these from certain directions. 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 Königsberg, Germany. The airports of this era used a paved "apron", which permitted night flying as well as landing heavier airplanes.
thumb|left|Airports in 2006 
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 glideslope. Additional lights indicated incorrect altitude and direction.

Following World War II, airport design began to become 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.

==Airport designation and naming==
<!-- This list doesn't need additional examples, Airport is an article not a list add airports to the List of airports page -->
Airports are uniquely represented by their ICAO airport code. International Air Transport Association (IATA) airport codes are often abbreviated forms of the common name of the airport, such as PHL for Philadelphia International Airport. Airports sometimes retain their previous IATA code when an airport's name is changed. O'Hare International Airport in Chicago retains the IATA code ORD, from its former name of Orchard Field.

The name of the airport itself can be its location, such as 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 ==

thumb|right|Baggage is scanned using [[X-ray machines, passengers walk through metal detectors]]

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.

== Airport operations ==
Away from the terminal, there is a large team of people who work to ensure aircraft can land, take off, and move around quickly and safely. 

===Air traffic control===

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.

thumb|View of the apron from the top floor observation room, [[Halifax International Airport]]

'''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.

===Traffic pattern===
All airports use a traffic pattern (often called a ''traffic circuit'' outside the U.S.) to assure smooth traffic flow between departing and arriving aircraft. Generally, this pattern is a circuit consisting of five "legs" that form a rectangle (two legs and the runway form one side, with the remaining legs forming three more sides). Each leg is named (see diagram), and ATC directs pilots on how to join and leave the circuit. Traffic patterns are flown at one specific altitude, usually 800 or 1,000 ft (244 m or 305 m) above ground level (AGL). Standard traffic patterns are ''left-handed'', meaning all turns are made to the left. Right-handed patterns do exist, usually because of obstacles such as a mountain, or to reduce noise for local residents. The predetermined circuit helps traffic flow smoothly because all pilots know what to expect, and helps reduce the chance of a mid-air collision.

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.

===Navigational aids===
thumb|right|Standard Visual Approach Slope Indicator
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 approach slope. Once the pilots can see the runway lights, they may continue with a visual landing.