Sometimes it's helpful to re-imagine a scenario, least we become fixated. Since there were no adverse conditions, much of our conjecture has focused on the plane and wondering why it would spontaneously break up.
So far we have conflicting statements of eye witnesses, but we may assume the mechanic is correct in his evaluation of the planes condition, and eye witnesses are correct in reports of unusual maneuvering. I have seen no reports of the weight of the two men, or the amount of fuel. That there was no fire was probably due to the seams of the tanks opening in the air and released the gas in a hurry. After meditating on the eye witness accounts, I can visualize the pilot losing consciousness or passing away, slumping forward and falling hard against the yoke. The passenger (who may never have touched aircraft controls before) reacts in an instant by pulling back, perhaps very hard. It would all take less than a second, and at this point, the aircraft has been fatally damaged. The results are tragic and incredibly sad, but the aircraft is blameless. This seems more likely than the plane just breaking apart. The only other thing I could imagine would be a bolt falling out of the mixer or one of the short push rods, leaving the aileron free to flutter. Wish we knew what the shiny thing was they saw. All just conjecture. Art N2666H PS I'd just buy another plane before replacing the center section - I don't think it's cost effective, and you can sometimes part an airplane out for more than you can often sell one.
