Primary finding
Probable cause
The airplane’s exceedance of the critical angle of attack, resulting in an aerodynamic stall and impact with terrain.
Investigator assessment
Analysis narrative
The pilot reported that the airplane’s hopper had been loaded with 300 gallons of water. During the takeoff roll, the airplane did not accelerate as expected so he initiated the emergency dump procedure to jettison the water. The airplane became airborne and the pilot maintained a high angle of attack to climb over trees near the end of the runway. The airplane subsequently experienced an aerodynamic stall, descended into an adjacent field, and impacted terrain. The left wing, right aileron, and elevator sustained substantial damage. The pilot said he suspected the airplane performance was affected by density altitude and he reported that there were no preaccident mechanical malfunctions or failures that would have precluded normal operation.