Thanks for the cleaner link, dig, but the side photos are nowhere near as interesting.
I think that helo is being flown off, the pilot is trying to get some translational lift to get airborne. The plowing is his attempt at some increased water speed, where he needs extra lift because of the water his aircraft has taken on and the OEI condition. The final plop is a lift-tow where he lets the nose go too far down and he loses control, just like a dynamic rollover - dynamic flip-over?