What happened
On April 11, 2019, at approximately 20:30 UTC, an Air Tractor AT-402A, registration PR-OFR, was performing agricultural spraying operations over a soybean plantation near Riachão das Neves, Bahia. The aircraft departed from a private agricultural landing strip located at Fazenda Savana to apply pesticides.
Upon completing the application, the pilot attempted to land on runway 27. At the time, wind conditions favored runway 09, meaning the approach to runway 27 involved a tailwind component. The pilot executed a maneuver similar to a "balloon" (a high-angle-of-attack turn used in agricultural flying) to intercept the runway at a 45-degree angle. During this approach, the aircraft was flying at an altitude between 300 and 500 feet with the flaps retracted.
The pilot reported a sudden sink rate just before touchdown. The aircraft made an unaligned contact with the runway, leading to a loss of directional control. The aircraft veered off the right side of the runway, resulting in the propeller tips striking the ground. The aircraft came to a stop near a rainwater drainage system, sustaining substantial damage to the engine, propeller, right wing, right flap, and right elevator. The pilot was uninjured.
The investigation
CENIPA's investigation confirmed that the pilot was properly licensed, qualified, and medically certified for the operation. The aircraft was also found to be airworthy, with all maintenance logs up to date and operating within weight and balance limits. Meteorological conditions were deemed favorable for flight.
The investigation focused on the pilot's approach technique and aircraft configuration. Investigators noted that the pilot did not follow a standard traffic pattern, opting instead for a direct intercept of the runway. Furthermore, the decision to land with flaps retracted and into a tailwind component was identified as critical to the sequence of events. The investigation also examined the physical environment, noting that the aircraft stopped near drainage sumps located at the edge of the runway.
Findings
- The pilot's decision to land with flaps retracted reduced the available lift during the approach.
- The approach was conducted with a tailwind component, increasing the difficulty of the landing.
- The pilot did not execute a standard traffic pattern, which limited the opportunity to stabilize the aircraft configuration.
- Inadequate use of flight controls contributed to the sudden sink rate and subsequent unaligned touchdown.
- Errors in pilot judgment and flight planning regarding wind and configuration were contributing factors.