[zeestephen]

One thing jumped out at me.

The recruits are calling Sergeant Jack Webb, “Sir.”

Is that a script error, or was the military protocol different in those days?

[oh8eleven]

The recruits are calling Sergeant Jack Webb, “Sir.” Is that a script error, or was the military protocol different in those days?
Marine boots call their DIs "sir" to teach them how to speak to officers.
Don't know when it started.