FAA database freshness & the unavailable warning

Rather than risk showing an out-of-date facility elevation — which would make every adjusted height wrong — the tool withholds results when its FAA data has expired and can't be refreshed.

If a lookup needs the FAA database but the stored copy has expired and a fresh copy cannot be downloaded at that moment, the tool will not display results for that facility. Instead it shows a warning with the valid time period of the stored database and asks you to try again shortly. This is deliberate: rather than risk presenting an out-of-date facility elevation (which would make every adjusted height wrong), the tool withholds the data until a current database is available.

Because the database is refreshed right at the end of its cycle, a brief window can occur where the old file has expired and the FAA has not yet finished publishing the new one. If you see the unavailable warning, waiting a few minutes and retrying will usually resolve it. Lookups that don't depend on the FAA database are never affected.

See Data sources for how facility identity and elevation are resolved in the first place.