What happened
The pilot was operating an agricultural aircraft on a wet and muddy runway when he encountered difficulties during the takeoff roll. Reports indicate that the previous takeoff attempt had required an excessive amount of runway distance. In response to this issue, the pilot instructed a helper to reduce the total load by 400 pounds before the next attempt.
Despite these adjustments, the aircraft continued to the end of the runway where it struck a berm. This impact caused the aircraft to become airborne in a nose-high attitude. However, the pilot was unable to maintain airspeed and altitude after leaving the ground. He closed the throttle and attempted to land in an adjacent cotton field. The aircraft could not be stopped before hitting a ditch.
The investigation
Post-accident examination of the hopper revealed it was nearly full. The owner stated that spray material, specifically sulfur, had remained in the hopper from previous flights. It was reported that the helper had not visually inspected the hopper before adding more sulfur for this flight. Additionally, the pilot admitted he did not visually check the quantity of the load before starting his takeoff.
Findings
Engine RPM and manifold pressure were reported as normal during the takeoff roll. The primary failure was attributed to the aircraft being overloaded due to residual material in the hopper that was not accounted for by either the helper or the pilot. This excess weight prevented the aircraft from achieving a safe climb gradient after becoming airborne at the end of the runway.
The aircraft was overloaded, leading to an inability to maintain altitude after takeoff. The pilot failed to verify the load, allowing residual sulfur to contribute to the excessive weight. The runway conditions were wet and muddy, further complicating the takeoff performance.
Safety message
Pilots must ensure accurate weight and balance calculations before every flight, especially when operating agricultural aircraft with hoppers that may retain residual material. Visual inspection of the load is critical to prevent unexpected overloading.