What happened
The flight began with the pilot flying a float plane from one lake to another, where a passenger was picked up. During the second takeoff attempt, the pilot encountered pitch problems while climbing, noting that the nose of the aircraft consistently tended to pitch upward.
At an altitude of approximately 50 to 100 feet, the aircraft began a left turn and the nose pitched down, resulting in a crash into the lake. The pilot was not injured.
The investigation
The investigation revealed that the pilot had not performed a weight and balance or a performance calculation prior to the takeoff. A review of the aircraft's weight and balance records from May 12, 1973, indicated a maximum gross weight of 1,294 pounds. However, the approximate weight of the aircraft during the accident flight was determined to be 1,420 pounds.
Upon inspection of the wreckage, the elevator trim was found in the full nose-down position.