NTSB Factual Report

On May 12, 2002, approximately 1400 Pacific daylight time, a Cook Coot A experimental-category amateur-built amphibian airplane, N12QQ, registered to and being flown by the pilot, was substantially damaged in a water landing on Lake Coeur d'Alene near Harrison, Idaho. The airline transport pilot, who was the sole occupant, received minor injuries in the accident. The flight was being operated in visual meteorological conditions, and according to the pilot, the winds were calm at the time of the accident. No flight plan had been filed for the 14 CFR 91 personal flight.

According to the pilot, who had already done a number of touch-and-go water landings that afternoon, he thought he was landing in an area where the water was "quiet." But just after touchdown, the aircraft encountered a boat wake and "...it just started porpoising." The second time the aircraft contacted the water, it hit another wake and pitched into the air again. The third time the aircraft contacted the water, the right wingtip was "buried," and the airframe sustained substantial damage. According to the pilot, there was no evidence that there had been any malfunction of the flight controls or any other aircraft system.

NTSB Probable Cause

The pilot's failure to detect an unsafe boat wake during the landing process, and his inadvertent initiation of a porpoise after coming in contact with the boat wake just after touchdown on a body of water. Factors include a large wake wave/swell created by the movement of a boat in the area where the pilot chose to land.