The non-certificated pilot reported he was testing the amphibious Avid’s engine and cooling system while maneuvering the airplane on a lake near Waterville, Minn. He added that he had “no intent to fly.”

He completed a number of passes across the lake. Before the last pass, he input full flaps, which resulted in the airplane inadvertently becoming airborne and climbing to about 100 feet.

He attempted to steer away from trees, but he lost control of the airplane, which then hit terrain.

The NTSB determined the probable cause as the non-certificated pilot’s failure to maintain control after an inadvertent takeoff, which resulted in collision with terrain.

NTSB Identification: CEN14LA411

This August 2014 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.