Wheels up

The point in a journey where you have officially left your starting point and begun traveling to your destination. Your bags are loaded, your kids are strapped in, your fully gassed up, food is packed, and you can officially announce your ETA. For people who run late all the time, this communicates that you have completed procrastinating and are done going back inside to grab “one more thing”. It comes from aviation jargon where your wheels leave the runway and you can fold up the landing gear.

In order to arrive at the park by noon, we need to be wheels up by 11:30!
OK, homie, I am finally wheels up, be there in 10 minutes.