Airport Airfield Coding

This is related to Real World and IF Aviation

Hello people!

I found many other posts with similar names to this but they do not really have the exact answer I am looking for.

Now for example: A big International Airport in the US called George International is called KGRG but the airfield nearby is called 7NK.

I am sorry if my example is not clear but my question is: Why are smaller airports/airfields don’t have the usual ICAO but instead a combination of letters and numbers like “6SJ” or “E3Y”. Is this because they are used to differentiate Airfields from Airports or did they “Run out” of ICAO codes?



I think the reason is that they don’t have ICAO or IATA codes so the identifier is used; using your example the FAA identifier is 7NK which is why it is used instead of an IATA or ICAO code in IF, and IRL afaik.

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I think it’s because it’s a private Own Airport that a farmer uses it for crop dusting a farm I see that a lot here I’m my town @Generic_Flyer

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The airports that have two letters and one number are usually public airports that do not meet the requirements to have an identifier with 3 letters. (a “K” is placed in front of the three letter identifier to get the ICAO code, which is where “K…” comes from) Airports get a three letter identification code when they have a tower, have a NAVAID, receive scheduled air carrier service, receive military airlift service, or are designated as a U.S. point of entry by U.S. Customs service.
Here’s the link to where I got all that information:
Pretty interesting, I didn’t know that stuff until now.


There are also some airports called things like CA36 and they don’t have IATA or ICAO codes, so I think the identifier is used in those cases as well