What happened
During the third tour flight of the day, the pilot was operating a float-equipped aircraft through weather that had been progressively worsening, characterized by light rain, fog on mountain ridges, and lowering ceilings. As the aircraft approached a mountain pass, the pilot attempted to initiate a climb by deploying a small amount of flaps while maintaining the existing cruise power setting.
At an airspeed of 80 knots, the aircraft maintained a climb rate of 200 feet per minute. Due to the nose-high attitude required for the climb, the pilot experienced limited visibility over the engine cowling. Upon suddenly spotting trees in the flight path, the pilot attempted an immediate left turn. This maneuver resulted in an aerodynamic stall, causing the aircraft to lose altitude and strike the tree-covered, mountainous terrain.
A passenger on board reported that while visibility was good and the aircraft did not enter low clouds, the aircraft performed a left turn and then a sharp left turn just prior to the impact. The passenger noted that the engine speed appeared to increase significantly immediately before the crash, though no unusual mechanical sounds were heard.
Findings
Post-accident inspections of the engine and airframe showed no evidence of mechanical failures or malfunctions that would have prevented the aircraft from operating normally. The pilot also reported no pre-accident mechanical anomalies. The primary factor in the accident was the failure to increase engine power during a climb configuration change.