Accident Overview
A propeller blade failed and separated while the aircraft was turning to begin a swath run at approximately 200 feet above ground level. The engine subsequently began severe vibration and also separated from the aircraft. Oil covered the windshield, preventing forward visibility.
The pilot reported being too busy trying to extinguish a fire to dump the load. During the forced landing, the aircraft collided with trees and then impacted the ground.
Propeller Examination
Metallurgical examination of the McCauley model P2A36098-8/S90AT-4 propeller, part number 122A34098-4, revealed that the failure was caused by fatigue. The propeller had accumulated about 411 hours of total flight time since new.