This guy died because he ran out of airspeed, due to trying to mishandle the aircraft out of a situation caused by his poor planning.
Nice Summary from The Wawa Zone.
Critical to the incident was that in the video, it appears that there were three seconds more or less when the pilot had warning of what was to come and did not recognise what was happening.
Everything being said about wind means little unfortunately as the aircraft stalled, incipient spin, then on entry to the water was in a fully developed spin.
While those ancient engines would have coughed up a furball or three with indignation at being pushed to full throttle, that would most likely have saved the day once the wings were levelled.
The point where the accident happened was the use of aileron to start a turn, the wing dropped and more aileron was used
in my opinion. Aileron drag then dug the hole and the aircraft and pilot fell in.
Safety Modeling
http://patientsafetyed.duhs.duke.edu...ss_cheese.html