What happened
On April 17, 2018, a Cessna 206F, registration PT-KON, was conducting a cargo flight from Boa Vista, RR, to Maturacá, AM, on behalf of a humanitarian organization. During the flight, the pilot encountered deteriorating weather conditions, including heavy cloud cover and precipitation, which prompted a precautionary landing at an unregistered landing site in the Novo Demini indigenous community.
After landing, heavy rainfall left the grass surface saturated and created puddles due to poor drainage in the area. Approximately 30 minutes after the rain ceased, the pilot attempted to depart from the site. During the takeoff roll, the aircraft experienced performance difficulties on the wet, uneven grass. The pilot attempted to abort the takeoff, but the aircraft could not be stopped within the available area, eventually exiting the strip and entering the surrounding vegetation. The aircraft sustained substantial damage, though the pilot remained uninjured.
The investigation
CENIPA's investigation examined the operational environment, maintenance records, and the pilot's decision-making process. Investigators found that the aircraft's airworthiness certificate was valid and the aircraft was within weight and balance limits. However, maintenance logs for the airframe, engine, and propeller were not up to date, which was noted as a regulatory violation.
The investigation also scrutinized the use of the landing site. The area in Novo Demini was not a registered or homologated aerodrome, which violates Brazilian aeronautical regulations. Furthermore, the investigation revealed that the operator's internal flight manual contained procedures for VFR flight above cloud layers that contradicted national standards, potentially encouraging pilots to operate in marginal meteorological conditions.
Findings
- The pilot's inadequate flight planning and failure to account for adverse weather conditions contributed to the need for a precautionary landing.
- An incorrect assessment of the takeoff area's condition, specifically the impact of wet grass and poor drainage on aircraft performance, led to the inability to stop the aircraft.
- The pilot's decision-making was influenced by an organizational culture that prioritized mission completion, which may have encouraged operating in marginal safety conditions.
- The use of an unregistered and uncertified landing strip increased the operational risks.
- Maintenance documentation for the engine, propeller, and airframe was not properly updated.