Class Charlie Airspace and the Two Little Words - Your Callsign - That Actually Clear You In
In Class Charlie airspace, you're cleared to enter the moment the controller says your callsign back - not when you hear the word 'cleared.'
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Ninety-One One Thirty, Class Charlie Airspace, and Why Hearing Your Own Callsign Is the Only Thing That Clears You In
To enter Class Charlie airspace you only need two-way radio communication established, which happens the moment ATC says your call sign.
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