Squawk code WITH mode s?
Dear guys,
this may be a stupid question, but I didn't find a good answer on google.
So I am speaking especially about commercial airliners: So I know that each airplane has a unique mode S Hex code which basically never changes. If you are beginning a flight, you will enter your flight number (or atc call sign) in your FMS. So with your hex code and your FMS callsign, the tower should get all he wants, right? Why will he give you a 4 letter squawk code? Does this have any benefit?
I am curious about the answers =).