In testimony before a Senate oversight committee today, former FEMA headman Michael Brown blamed the Department of Homeland Security for the government’s slow response to Hurricane Katrina. “I told the staff … that I expected them to cut every piece of red tape, do everything they could, that it was balls to the wall,” Brown testified. A skeptical Sen. Norm Coleman responded: “Can you show me … your very clear directives to go, quote, ‘balls to the walls,’ to clear up this situation, to fix it?” Where does the expression “balls to the wall” come from?

Somewhat disappointingly, it has nothing to do with hammers, nails, and a particularly gruesome way of treating an enemy. The expression comes from the world of military aviation. In many planes, control sticks are topped with a ball-shaped grip. One such control is the throttle—to get maximum power you push it all the way forward, to the front of the cockpit, or firewall (so-called because it prevents an engine fire from reaching the rest of the plane). Another control is the joystick—pushing it forward sends a plane into a dive. So, literally pushing the balls to the (fire)wall would put a plane into a maximum-speed dive, and figuratively going balls to the wall is doing something all-out, with maximum effort. The phrase is essentially the aeronautical equivalent of the automotive “pedal to the metal.”

The expression is first found in military-aviation sources that date from the Vietnam War, and it was recorded in the slang of U.S. Air Force Academy cadets in 1969. Although no evidence from the period has come to light, Korean War veterans have also reliably claimed to have used the expression in the 1950s. An earlier parallel is balls-out, in the same sense, which is found in military-aviation sources that date from World War II. (The phrase was also painted on the nose of at least one fighter plane.) In both cases it’s likely that the possibility of an anatomical interpretation has helped the expressions gain wider use.

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The Explainer thanks Dr. Jeff Underwood and Doug Lantry of the National Museum of the U.S. Air Force.