Naming of Servers

All of these are names of airports no longer in use:

Kaitak: As you mentioned, the former Hong Kong International airport

Croydon: Former airport in London

Devau: Probably after the Kaliningrad airport

Fornebu: Former airport for Oslo

Nicosia: Airport on Cyprus, still exists but not in operation due to its location and the ongoing troubles.

Idlewild: The name of the New York airport currently known as John F. Kennedy Airport

Tempelhof: Name of one of the Berlin airports, closed a few years ago.