GeoNames Forum

Adding IATA codes for the cities showed message "IATA codes are for airports only" (something like that).
I'm sure it isn't true. According to the IATA website there is airport codes and city codes. Fir example, try to find "STN" (location code for London Stansted Airport). You can see there is "STN" - airport code, but "LON" - city code.
Now try to find "CHI" (city code for Chicago) and you will see many airports in Chicago.
So IATA assigns TLAs not only to airports.

you are right we have removed iata from the featurecode check. We will also change the Duplicatecheck to take the featureClass into account:
http://qa.geonames.org/qa/chkAirportCodesDuplicate.html

Marc