With the dramatic increase in hobbyist-created airports, we are getting conflicts in airport IDs. We are currently limited to 5 ascii characters as an ID. Expanding this limitation to 16 characters would allow many more IDs without conflict.
There is also a limitation of about 9000 meters for an apron (for example) to be shown in the sim based on the airports location. You can set the airport radius to 10000 or more, but it will not aid the display of the apron. (Aprons being essential to cover anomalies in the Bing aerial imagery). By expanding the airport IDs, we could create a 'fake' airport area, and add aprons in areas in which there are no actual airports.
If this were increased to 16 characters, we'd have an almost unlimited ability to add heliports, water ports, ultralight ports, glider ports, military ports, and of course fictional ports. We could prefix them, for example, as AP, HE, WA, UL, GL, MI, and FI, and still have 14 characters to ID the "airport" (AP being an accepted real-world ID). It would solve a lot of problems like this.
Also, some real-world examples of airport IDs are greater than 5 characters:
|RU-2510||Greem Bell Air Base||Khatanga||81.15||64.33||30|
|BR-0238||Valença do Piauí Airport||Valença do Piauí||-6.388103||-41.763983|
There are dozens of actual examples that now require abbreviated or even fictional IDs to be used in the sim.