The pilot stated to the NTSB that he was trying to takeoff and when he was about 1/4 of the distance from the end of the runway he attempted to pull back on the control yoke and lift off, but nothing happened. He said that at the time he noticed that the airspeed was about 60 knots, but yet he could not raise the nose of the airplane, so he applied the brakes in an attempt to stop, and the airplane departed off the end of the runway. He stated, he did not remove the control lock prior to flight, and added that prior to the accident there were no mechanical failures or malfunctions of the airplane or any of its systems.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot's improper preflight planning/preparation which resulted in the airplane's gust lock being left installed, which resulted in the airplane not being able lift off during the takeoff roll, and damage to the airplane when it overran the runway and crashed into the water at the end of the runway.