Most of my friends, both on PF and in person, are accustomed to me using the phrase "balls-to-the-wall" to indicate a flat-out effort. It never occurred to me, until someone (in person) mentioned it earlier today, that it might be deemed offensive by some. I want to explain that there is no reference to genitalia implied. It's pilot terminology dating back to WWII. The throttle(s), mixture controls, and propellor pitch controls of almost all fighter and bomber aircraft resided on a pedestal. They were usually on a left-hand "quadrant" in a fighter or centrally in a bomber (so the co-pilot had equal access). The tops of the levers were spherical knobs referred to as "balls". The max setting for all of them was to the top of the slots, as close as possible to the firewall between the cockpit and the engine compartment. The throttle part should be self-explanatory, but I will explain for the benefit of ground-hogs that the mixture leans out or enriches the air:fuel ratio going through the carb. Flattening the pitch of the propellors is akin to downshifting a car to get that extra kick in the ***. So, basically, the term "balls-to-the-wall" translates as "firewall everything and hang onto your hat". If my usage of the phrase has offended anyone in the past, I offer my profound apologies. It just never occurred to me that it would be taken out of context, but on the other hand most readers of this are very young and/or non-pilots. I'll just have to get used to that fact and adjust my posts accordingly.