Reply #21: Actually, it is not sexist at all.

[av8rdave]

In the older days of aviation, where the throttle quadrant consisted of throttle, mixture and prop levers, the tops of the levers were given different shapes for simplicity. "Balls to the wall" referred to moving the ball topped levers all the way forward, towards the firewall. (In fact, "firewall" is also a term for full throttle).

Nothing more, nothing less.

The term is no more sexist than is "cockpit." (Which also has no sex - related origins).

Edited for crappy grammar.