What happened
On July 31, 2016, an EMB-820C Navajo, registration PT-EFQ, was performing a cargo and personnel transport flight from Cuiabá to Londrina, Brazil. During the approach to the Londrina Aerodrome (SBLO), the crew declared an emergency, reporting a loss of power in the left engine. While approximately 5 NM from the threshold of runway 13, the aircraft struck an electric power grid and subsequently collided with a transport company's shed. The impact destroyed the aircraft and caused a fire that ignited a truck parked at the site. All eight fatalities (two pilots and six passengers) occurred at the crash site.
The investigation
CENIPA's investigation focused on the mechanical state of the engines and the crew's management of the emergency. Investigators found that the aircraft's logbook records for the airframe, engines, and propellers were outdated. While the aircraft had undergone a major inspection earlier in 2016, the investigation identified significant mechanical discrepancies in both powerplants. Furthermore, the investigation examined the crew's performance, noting that the copilot had very limited experience with this specific aircraft model and the installed Garmin GTN 650 navigation system. The investigation also looked into the decision-making process regarding the flight's departure from Cuiabá, as a warning light had been active on the instrument panel prior to takeoff.
Findings
- Engine malfunction: The primary cause was a simultaneous failure of both engines. The right engine suffered from a fuel leak due to a loose nut on the distributor and a poorly adjusted turbocharger bypass valve. The left engine experienced clogged fuel nozzles caused by an accumulation of soil and fuel impurities.
- Maintenance issues: The aircraft's maintenance records were outdated, and the presence of contaminants in the fuel nozzles may have been linked to the aircraft's long period of inactivity during a previous overhaul.
- Crew performance: Factors such as reduced communication assertiveness between the pilots, potential anxiety, and a lack of familiarity with the RNAV navigation system may have hindered effective emergency management and led to a misidentification of the approach path.
- Operational decisions: The aircraft departed Cuiabá while a warning light was illuminated, and the aircraft was operating above its maximum weight limit during takeoff.