"BALLS TO THE WALL" is a term that pilots use that has owes it’s origins to the early days of flight when the Throttle, Prop control, and mixture had knobs that made it easier for pilots to grip … Full forward to the instrument panel …
St Louis Approach control …
St. Louis Approach to United: "United 123 best forward speed to the outer marker, you’re number one."
United 123 (male voice): "Roger, balls to the wall."
St. Louis Approach to American: "American 4321, you’re number two behind a United 737, follow him, cleared visual, best forward speed."
American 4321 (female voice): "Well I can’t do balls to the wall, but I can do wide open."
Unidentified Pilot (male voice): "Is American hiring ??"