Ahhh, APCO is the law enforcement kind. Always thought that one sounded dumb. I meant the old WW2 one that goes something like "Able, Baker, Charlie, Dog, Easy" etc. And yes, foreign pilots often have only the bare minimum English skill level. It's fine when everything is normal, but when STHF, it's a hot mess (Air China I'm looking at you). Those phonetic letters are the only thing that save the day unless your speak their native language.