I think orientation does matter, and that a water entry might be more survivable with a vertical entry. Think about diving from a high-dive versus a belly flop.

I think orientation does matter, and that a water entry might be more survivable with a vertical entry. Think about diving from a high-dive versus a belly flop. At terminal, you’re still likely to break legs or die from entry in a vertical position, but the surface area hitting the water is a lot less if you’re feet first, plus you’d have shoes on, etc. Check out the world record cliff jump https://www.dailymotion.com/video/x32e3od https://www.dailymotion.com/video/x32e3od Terminal in stand-up is indeed much higher than terminal in the flat position. A perfect stand-up / head-down is around 180mph typically, while flat is around 120mph, give or take depending on body shape & density. But it takes time to accelerate, long enough that I think if you stood up quickly you’d still be around the flat-position velocity. The maximum you can theoretically accelerate is about 22 mph/s, but you’re starting from terminal with tons of drag, so I think it would take 5-10 seconds to reach 180mph, and you can go from flat to stand-up in 1-2 seconds.