Primary finding
Probable cause
The pilot’s loss of airplane control after an encounter with windshear during takeoff which, resulted in a hard water landing.
Investigator assessment
Analysis narrative
The pilot of the amphibious airplane reported that, during the tailwind departure from the mountain lake, the airplane was about 40 ft above water level, at an airspeed of 57 miles per hour (mph), when the airplane encountered windshear. The airspeed decreased suddenly by 10-15 mph and the airplane entered a 600 foot per minute descent rate that the airplane was unable to out climb with takeoff power. The airplane subsequently collided hard with the water and bounced before coming to rest. The wings and fuselage were substantially damaged. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.