AF1 using 'empty callsign' on final approach Prestwick Scotland
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⠀⠀⠀⣖⠲⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⠉⡇⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠸⡆⠹⡀⣠⢤⡄⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡏⠀⡧⢤⡄⠀⠀⠀⠀⠀
⠀⠀⠀⠀⡧⢄⣹⣅⣜⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⠁⠀⢹⠚⠃⠀⠀⠀⠀⠀
⠀⣀⠴⢒⣉⡹⣶⣤⣀⡉⠉⠒⠒⠒⠤⠤⣀⣀⣀⠇⠀⠀⢸⠠⣄⠀⠀⠀⠀⠀
⠀⠈⠉⠁⠀⠀⠀⠉⠒⠯⣟⣲⠦⣤⣀⡀⠀⠀⠈⠉⠉⠉⠛⠒⠻⢥⣀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⠙⣲⡬⠭⠿⢷⣦⣤⢄⣀⠀⠀⠚⠛⠛⠓⢦⡀
⠀⠀⠀⠀⠀⠀⠀⢀⣀⠤⠴⠚⠉⠁⠀⠀⠀⠀⣀⣉⡽⣕⣯⡉⠉⠉⠑⢒⣒⡾
⠀⠀⣀⡠⠴⠒⠉⠉⠀⢀⣀⣀⠤⡤⢶⣶⣋⠉⠉⠀⠀⠀⠈⠉⠉⠉⠉⠉⠁⠀
⣖⣉⣁⣠⠤⠶⡶⡶⢍⡉⠀⠀⠀⠙⠒⠯⠜⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠁⠀⠀⠀⠀⠑⢦⣯⠇