For crossword puzzles and other word games, it is sometimes useful to have a table of the NATO alphabet.
The Atlanta airport has five concourses, A through E, and the underground train that connects them uses the Nato alphabet to make the names of the concourses clear. Thus, it announces that it has arrived at "Concourse A, as in Alpha". However, there has been one alteration, for it also announces that it has arrived at "Concourse D, as in David". The reason, of course, is that Delta Airlines uses Atlanta as a hub, and the hapless hurried traveler might otherwise hop off at D concourse thinking he had arrived at the "Delta Concourse".
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