I just learned a few months ago that no US airport code is allowed to start with K, N, or W because those first initials are reserved for radio stations in the USA!
So now these make some sense halfway:
nEWaRk NJ
nEW berN NC
wILMington NC
wILminGton DE
MCI for Kansas City instead of KCI: Must be embarrassing for all the Sprint Telephone employees with their competitor's name on their bag tags

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