Accident Summary
A pilot was conducting aerial application operations with sulfur when an explosion occurred, blowing the lid off the hopper. The explosion was immediately followed by an in-flight fire. While the pilot maneuvered for an emergency landing, the airplane collided with trees. The aircraft came to rest inverted, and a post-crash fire ensued, resulting in substantial damage.
Aircraft Records Examination
Examination of the airplane's maintenance records revealed no entry indicating compliance with Airworthiness Directive (AD) 48-34-02. This directive mandates five fire prevention measures: proper location of the engine exhaust, bonding of the fuselage, agitator bearing design and maintenance, hopper gate construction and materials, and incorporation of fire-resistant material in the lower fuselage.
The absence of a compliance entry suggests that the required fire prevention modifications may not have been implemented on the accident aircraft.