What happened
On February 12, 2018, an Air Tractor AT-402A, registration PR-TNO, was performing an agricultural spraying mission near Itapetininga, Brazil. The aircraft departed from a private landing strip used for agricultural purposes. Following the completion of the mission, the pilot landed on the strip, which had become wet due to recent isolated rain showers in the area.
Upon touchdown, the pilot was unable to maintain directional control. The aircraft veered to the left, and the left wingtip collided with an adjacent orange orchard. This impact caused the aircraft to undergo a 180-degree counter-clockwise rotation. The aircraft sustained substantial damage, though the pilot remained uninjured.
The investigation
CENIPA investigators examined the landing site and the operator's safety management protocols. The investigation revealed that while the landing area was suitable for the aircraft's performance, the strip lacked any formal markings or boundaries to delineate the operational space. Furthermore, a 40-centimeter depression was identified on the left side of the runway in the direction of the landing.
The investigation also reviewed the operator's Safety Management System (SMS). Although a risk assessment had been conducted for the landing site, the assessment failed to identify the lack of runway markings and the surface depression as specific hazards. Additionally, while the risk of a wet runway was noted, the only mitigation measure recorded was a general warning about obstacles, which proved insufficient. The investigation noted that the individual responsible for safety management also held the role of responsible manager, potentially leading to oversight due to workload or conflicting priorities.
Findings
- The pilot failed to maintain directional control on the wet surface.
- The aircraft's left main landing gear passed over a surface depression, which exacerbated the leftward veer.
- Inefficient risk management failed to identify the hazards posed by the lack of runway delimitation and the track depression.
- The operator's safety manual lacked specific procedures or prohibitions for operating on wet landing strips.
- The pilot's judgment regarding additional mitigation measures for the wet surface was a contributing factor.