Primary finding
Probable cause
The pilot’s failure to maintain control during takeoff on choppy water conditions.
Investigator assessment
Analysis narrative
The pilot reported that, during takeoff from a lake, the airplane started to bounce from wave to wave, and it eventually porpoised. When the pilot reduced power to abort the takeoff, the left wingtip ski struck a wave, and the airplane yawed to the left. The right wing then struck the water, and the airplane abruptly stopped. The fuselage and wing spars were substantially damaged. The pilot reported that the wind on the lake at the time of the accident was about 18 knots and that the waves were about 12 to 15 inches high. The pilot reported that the highest waves he had previously encountered in this airplane were 10 to 12 inches high. The pilot reported no preimpact mechanical failures or malfunctions with the airplane that would have precluded normal operation.
Source record
Factual narrative
The pilot reported that during takeoff from a lake, the airplane started to bounce from wave to wave and eventually developed into a porpoise. As power was reduced to abort the takeoff, the left wing tip ski struck a wave and the airplane yawed to the left. The right wing then struck the water and the airplane came to an abrupt stop. The fuselage and wing spars were substantially damaged. The pilot reported that the wind on the lake at the time of the accident was about 18 knots and the waves were about 12-15 inches high. The pilot reported that prior to this; the largest waves the airplane has encountered were 10-12 inches high. The pilot reported no mechanical failures or malfunctions with the airplane that would have precluded normal operations.