F.A. ? Can't remember the detail now, so doubtless will be corrected. Aircraft talking to a USA controller somewhere ? in the US used an offensive word, I 'think' the F word, and was immediately chastised by the controller, which resulted in many aircraft also on the freq. to deliberately repeat it e.g. " I didn't say F" and "Did you say F?" " I just heard someone say F " " Who said F ? " " Did I hear F ? " All without any identifying call signs. 0
Such fun.