Dr. Lecter
Contributor
Man has no one ever gone whitewater rafting. Yes you need to know the technique for getting out of a hydraulic but the basic idea is correct ball up inflate if the fall pushes you down when you bounce off the bottom you should be pushed out too. I got a great video of a guy going over Pillow Rock in West Virginia and popping up 50 yards down stream.
In addition to having gone on whitewater rafting trips (even guided a couple summers when I was younger), I've done the New and Gauley rivers in a whitewater canoe, including a dam release day on the upper Gauley. Pillow rock is fun, I've done it; but turning yourself into floaty agitator ball in a real hydraulic is a terrible idea.
If you get stuck in a hydraulic current, you want to get negative, be as close to the bottom as possible and swim/hand over hand downstream to get out of it. If you head up, you're just going to get pulled back, smashed into whatever's causing the circular backflow in the first place, and then pulled back under. Eventually, yeah, you'll get spit out.