The aeroway= key is used to hold all the main details for an aerodrome. Preferably this is the airport's ARP, if documented (for smaller terrains, it usually isn't), but it can also be associated with the area around the perimeter of the aerodrome.
For (very) small facilities, perhaps consisting of no more than an airstrip, aeroway=airstrip can alternatively be used, and is preferred in certain countries.
For aviation terrains used only by helicopters, use aeroway=heliport instead.
Either create an area (aka "a closed way") – or a multipolygon relation for some complex shapes – around the extent of the airport land (often co-incident with a barrier of some kind).
Or draw a node in the centre of the aerodrome and tag with at least aeroway=.
Elevation. Possibly at arbitrary position, tower, runway centre point, etc. See individual elevations on runways and their endpoints for more specificity.
3-character code issued by the IATA and commonly known and used to identify airports for commercial air transport. Only rarely present for smaller/private aerodromes. Can be checked at https://www.iata.org/en/publications/directories/code-search/ Note: since 2021 or so, IATA have been cleaning the list, unassigning many codes that were unused anyway.
4-letter code issued by the ICAO, or the national Civil Aviation Authority. w:Location identifier#ICAO location indicator Mandatory in some (smaller) countries, often unassigned in larger countries.
Name by which the aerodrome is commonly known. Best taken from an official source, such as the AIP, or other authoritative listing, or from the aerodrome operator's website.
Source(s) of information present in tags, semi-colon-delimited if necessary.
variation=*
dd[.d] [E|W] [yyyy[-mm[-dd]]] [d.d E|W]. Indicates the magnetic variation (Magnetic variation declination) of the magnetic north pole relative to the geographic north pole, the date of measurement, and possibly the rate of change. Example: "12.8 E 2011-11-17 0.1 W" means that a compass will read north 12.8 degrees east (clockwise) of geographic north on 2011-11-17, and that variation currently changes at a rate of 0.1 degree west per year.
Type of aerodrome (international, regional, etc.) This classification has never been clearly delimited. One useage is quite consistent, though, at least in Europe and probably beyond: aerodrome:type=seaplane.
3- or 4-character code issued by the FAA. Usually the same as the IATA code, but not always [1]. Present for smaller/private airports when iata tag may not be.
FAA:LFSN=*
The FAA's Landing Facility Site Number - a unique identifier for airports in the US. There is generally no reason to edit this value - it is used to refer back to the FAA database for synchronization of imports. Example: "01818.*A" is the LFSN for LAX.
Key to source documents. Example: when source=FAA, you may see source_ref=nnnnnAD, which indicates the document number of the FAA Airport Diagram, which are at http://aeronav.faa.gov/d-tpp/vvvv/nnnnnAD.PDF where vvvv is the version number (incremented every 56 days).
aeroway =
