I said I'd make a fool of myself
Not at all. One of the best ways of learning things is to have people on PPRuNe correct your mis-understandings - I've learnt loads by posting on here and having other people put me right!
Presumeably if you apply for a special callsgn it must be globally unique?
Yes. In fact, it can't even sound rougly like any other existing call-sign. And it has to be pronouncable to our international fellow aviators. And probably lots of other stuff too!
FFF
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