There are approximately 14,400 private-use (closed to the public) and 5,000 public-use (open to the public) airports, heliports, and seaplane bases. Approximately 3,300 of these public-use facilities are included in the National Plan of Integrated Airport Systems (NPIAS). Airports or portions of airports, included in the NPIAS may be considered for AIP funding. An airport is defined in the law as any area of land or water used or intended for landing or takeoff of aircraft including appurtenant area used or intended for airport buildings, facilities, as well as rights of way together with the buildings and facilities. Special types of facilities such as seaplane bases and heliports are included in the airport categories listed below.
The law categorizes airports by type of activities, including commercial service, primary, cargo service, reliever, and general aviation airports, as shown below:
|Statutory Definition||Criteria||Also referred to as:|
|Commercial Service||Publicly owned airports with at least 2,500 annual enplanements and scheduled air carrier service (§47102(7)). Primary airports are a commercial service airport with more than 10,000 annual enplanements (§47102(16)).|
||Receives 1 percent or more of the annual U.S. commercial enplanements||Primary|
||Receives 0.25 to 1.0 percent of the annual U.S. commercial enplanements||Primary|
||Receives 0.05 to 0.25 percent of the annual U.S. commercial enplanements||Primary|
||Receives less than 0.05 percent but more than 10,000 of the annual U.S. commercial enplanements||Primary|
||Also referred to as nonhub nonprimary, these airports have scheduled passenger service and between 2,500 and 10,000 annual enplanements.||Nonprimary|
|Reliever||An airport designated by the Secretary of Transportation to relieve congestion at a commercial service airport and to provide more general aviation access to the overall community (§47102(23)).||Nonprimary|
|General Aviation||A public-use airport that does not have scheduled service or has scheduled service with less than 2,500 passenger boardings each year (§47102(8)).||Nonprimary|
- Commercial Service Airports are publicly owned airports that have at least 2,500 passenger boardings each calendar year and receive scheduled passenger service. Passenger boardings refer to revenue passenger boardings on an aircraft in service in air commerce whether or not in scheduled service. The definition also includes passengers who continue on an aircraft in international flight that stops at an airport in any of the 50 States for a non-traffic purpose, such as refueling or aircraft maintenance rather than passenger activity. Passenger boardings at airports that receive scheduled passenger service are also referred to as Enplanements.
- Nonprimary Commercial Service Airports are Commercial Service Airports that have at least 2,500 and no more than 10,000 passenger boardings each year.
- Primary Airports are Commercial Service Airports that have more than 10,000 passenger boardings each year. Hub categories for Primary Airports are defined as a percentage of total passenger boardings within the United States in the most current calendar year ending before the start of the current fiscal year. For example, calendar year 2014 data are used for fiscal year 2016 since the fiscal year began 9 months after the end of that calendar year. The table above depicts the formulae used for the definition of airport categories based on statutory provisions cited within the table, including Hub Type described in 49 USC 47102.
- Cargo Service Airports are airports that, in addition to any other air transportation services that may be available, are served by aircraft providing air transportation of only cargo with a total annual landed weight of more than 100 million pounds. "Landed weight" means the weight of aircraft transporting only cargo in intrastate, interstate, and foreign air transportation. An airport may be both a commercial service and a cargo service airport.
- Reliever Airports are airports designated by the FAA to relieve congestion at Commercial Service Airports and to provide improved general aviation access to the overall community. These may be publicly or privately-owned.
- General Aviation Airports are public-use airports that do not have scheduled service or have less than 2,500 annual passenger boardings (49 USC 47102(8)). Approximately 88 percent of airports included in the NPIAS are general aviation.
In cooperation with the aviation community, FAA completed two top down reviews of the existing network of general aviation facilities included in the NPIAS. The results of these efforts are contained in two reports (General Aviation Airports: A National Asset) and have been fully incorporated into the biennial NPIAS. The airport roles capture the diverse functions and economic contributions GA airports make to their communities and the Nation. Five categories for airports serving general aviation (includes nonprimary commercial service, relievers and general aviation) were developed based on existing activity levels. These roles are shown below. The criteria are contained in FAA Order 5090.5 and Appendix C of the Current Published NPIAS.
|If a nonprimary airport is classified as:||It fulfills this role in the system:|
|National||Support the national airport system by providing communities access to national and international markets in multiple States and throughout the United States. National airports have very high levels of aviation activity with many jets and multiengine propeller aircraft.|
|Regional||Support regional economies by connecting communities to regional and national markets. Generally located in metropolitan areas and serve relatively large populations. Regional airports have high levels of activity with some jets and multiengine propeller aircraft. The metropolitan areas in which regional airports are located can be Metropolitan Statistical Areas with an urban core population of at least 50,000 or Micropolitan Statistical Areas with a core urban population between 10,000 and 50,000.|
|Local||Supplement local communities by providing access to markets within a State or immediate region. Local airports are most often located near larger population centers, but not necessarily in metropolitan or micropolitan areas. Most of the flying at local airports is by piston aircraft in support of business and personal needs. These airports typically accommodate flight training, emergency services, and charter passenger service.|
|Basic||Links the community with the national airport system and supports general aviation activities, such as emergency response, air ambulance service, flight training, and personal flying. Most of the flying at basic airports is self-piloted for business and personal reasons using propeller-driven aircraft. They often fulfill their role with a single runway or helipad and minimal infrastructure.|
|Unclassified||Currently in the NPIAS but with limited activity.|