At 1115 Eastern time, the airplane experienced a loss of control during an approach for landing. Visual conditions prevailed. The private pilot was killed. A witness observed the accident seaplane on a slow climbout with a high angle of attack. It appeared to the witness as if the pilot was hanging the aircraft on the prop. The seaplane barely cleared the trees at the edge of the lake and made a left climbing turn as if the pilot was trying to gain altitude. The seaplane appeared to turn onto a base leg for landing, then made a steep left turn and entered a left spin. The seaplane rotated about one complete turn before it impacted the lake in a nose-down attitude.
