What happened
During the takeoff phase of flight, the pilot was instructed by the tower to utilize runway 25. The pilot observed that the wind direction was variable between 120 and 150 degrees and noted that the windsock was positioned at a 90-degree angle to the runway. Seeking more favorable conditions, the pilot waited for the wind to shift to favor runway 25 before initiating the takeoff roll.
As the aircraft reached the point where the tail began to lift off the runway, it was struck by a very violent gust of wind. This sudden gust caused the wing to lift and resulted in the airplane nosed over on the runway.
The investigation
An examination of aviation surface weather observations indicated that winds at the time of the accident were from 180 degrees at 15 knots. A METAR recorded approximately one hour prior to the accident at 1556 reported winds from 180 degrees at 18 knots, with no wind direction variability recorded on the Department of Commerce Form MF1M-10C.
The local controller reported that at the time of takeoff clearance, he provided updated wind information consisting of 180 degrees at 12 knots.