Like russellward said. And per Urban Dictionary:
a term used by pilots. when accelerating quickly, the throttle is pushed all the way to the panel and the throttle lever (ball) actually touches the panel (wall). Hence, balls to the wall.
"Balls out," as I know it refers to the old flyball speed governors found on steam turbines. As the turbine speed is raised the flyballs lift farther from center until at maximum speed they are "balls out."
Do I get a yellow card, Footski?
