Water landings
A couple of years ago a guy offered to show me how he waterskiied with no skis, just bare feet. There's a secret, it turns out.
One has to get up to 45 MPH when it's calm, and the water turns "hard". Below 42 MPH it's too "soft". As the boat passed 45 MPH he stood right up and skiied as well as one would please, sort of. Not the maneuverability wone would want, but certainly doing fine.
I imagine an airplane hitting water at over 45 MPH is going to experience one helluva jolt.
Arf