Pilots and air traffic controllers saying "tree," "fife," and "niner" instead of three, five, and nine. What is that about?

Does the alphabet matter in broadcasting any more ... rather than their full (and more local-sounding) call letters. Because radio call letters fired up more than 100 years ago, some of them ...

We use letters selected from a standard phonetic ... I memorized the NATO alphabet for use in ham radio. But there are times, like spelling my name for someone on the phone, where it’s come ...