South America

Contributing factors.
- Control skills - undetermined
Inadequate use of aircraft controls, particularly as regards the mode of operation of the Autothrottle in use and the non-reduction of the IDLE power levers at touch down, may have led to a conflict between pilots when performing the landing and the automation logic active during approach. In addition, the use of only one reverse (on the right engine) and placing the left throttle lever at maximum takeoff power resulted in an asymmetric thrust that contributed to the loss of control on the ground.
- Attitude - undetermined
The adoption of practices different from the aircraft manual denoted an attitude of noncompliance with the procedures provided, which contributed to put the equipment in an unexpected condition: non-automatic opening of ground spoilers and asymmetric thrust of the engines. These factors required additional pilot intervention (hand control), which may have made it difficult to manage the circumstances that followed the touch and led to the runway excursion.
- Crew Resource Management - a contributor
The involvement of the PM in commanding the aircraft during the events leading up to the runway excursion to the detriment of its primary responsibility, which would be to monitor systems and assist the PF in conducting the flight, characterized an inefficiency in harnessing the human resources available for the airplane operation. Thus, the improper management of the tasks assigned to each crewmember and the non-observance of the CRM principles delayed the identification of the root cause of the aircraft abnormal behavior.
- Organizational culture - a contributor
The reliance on the crew's technical capacity, based on their previous aviation experience, has fostered an informal organizational environment. This informality contributed to the adoption of practices that differed from the anticipated procedures regarding the management and operation of the aircraft. This not compliance with the procedures highlights a lack of safety culture, as lessons learnt from previous similar accidents (such as those in Irkutsk and Congonhas involving landing using only one reverse and pushing the thrust levers forward), have apparently not been taken into account at the airline level.
- Piloting judgment - undetermined
The habit of not reducing the throttle lever to the IDLE position when passing at 20ft diverged from the procedures contained in the aircraft-operating manual and prevented the automatic opening of ground spoilers. It is possible that the consequences of this adaptation of the procedure related to the operation of the airplane were not adequately evaluated, which made it difficult to understand and manage the condition experienced.
- Perception - a contributor
Failure to perceive the position of the left lever denoted a lowering of the crew's situational awareness, as it apparently only realized the real cause of the aircraft yaw when the runway excursion was already underway.
- Decision-making process - a contributor
An inaccurate assessment of the causes that would justify the behavior of the aircraft during the landing resulted in a delay in the application of the necessary power reduction procedure, that is, repositioning the left engine power lever.

The accident was the consequence of a loss of situational awareness of the pilots, by not making a continuous surveillance during the VFR flight in good weather conditions, not determining timely the corrections of direction or altitude, which finally led them to fail to fly over the ground of the new route adopted in flight, generating a probable aerodynamic loss at the limit of the performance of the aircraft, occurring a CFIT accident.
Contributing factors:
- Limited or poor use of the available GPS Terrain Proximity Warning system.
- Poor or erroneous appreciation of the weather conditions at the beginning of the flight, which led them to vary the route to fly over terrain with higher elevation.
- Limited appreciation of terrain height on the new route in relation to the selected cruising altitude.

The following findings were identified:
- Execution of a take-off with a weight approximately 17% higher than the maximum gross operating weight (MTOW) established for the C208B aircraft.
- Limited climb rate with signs of lift loss due to the low performance given by the overweight during the initial climb phase.
- Forced landing in mountainous terrain due to loss of lift caused by overweight during the initial climb.
- Absence in the identification of the risks associated to an overweight operation of the aircraft.
- Lack of supervision by the Aircraft Operator in relation to the dispatch of aircraft operating from the outside at the main base of operation.

Contributing factors.
- Communication – undetermined
It is possible that difficulties for the dialogue between pilots on matters related to the operation of the aircraft have favored a prejudicial scenario to the expression of assertiveness in the communication in the cabin, interfering in the effective management of the presented abnormal condition.
- Team dynamics – undetermined
It is possible that a more passive posture of the copilot combined with the commander's decisions and actions from the presentation of the abnormal condition in flight interfered with the quality of the team's integration and in the efficiency of the cabin dynamics during the occurrence, bringing losses to the emergency management presented.
- Emotional state – undetermined
It is not possible to discard the hypothesis that a more anxious emotional state of the pilots contributed to an inaccurate evaluation of the operational context experienced, favoring ineffective judgments, decisions and actions to manage the abnormal condition presented.
- Aircraft maintenance – a contributor
On the right engine, it was found that the fuel tube fixing nut that left the distributor for No. 3 cylinder was loose, favoring the fuel leakage, as well as the bypass valve clamp of the turbocharger that was bad adjusted, providing leakage of gases from the exhaust that would be directed to the compressor and, later to the engine, to equalize its power. On the left engine, impurity composed of an agglomerate of soil and fuel were found on the side of the nozzles n° 2, 4 and 6, which migrated to the inside of these nozzles, causing them to become clogged. It was not possible to determine the origin of this material, but there is a possibility that it may have been deposited during the long period the aircraft spent in the maintenance shop, undergoing general overhaul and the revitalization of its interior (13DEC2012 until 29APR2016).
- Insufficient pilot’s experience – undetermined
The pilots had little experience with the GARMIN GTN 650 navigation system. The lack of familiarity with this equipment may have favored the misidentification of the approach fixes for Londrina. This way, it is possible that they have calculated their descent to the final approach fix (waypoint LO013), believing that it was the position relative to threshold 13 (waypoint RWY13).
- Decision-making process – undetermined
The decision to take off from Cuiabá to Londrina without the identification of the reason for the warning light to be ON in the alarm panel and the possible late declaration of the emergency condition showed little adequate decisions that may have increased the level of criticality of the occurrence.
- Support systems – undetermined
The similarity of the waypoints names in the RNAV procedure, associated with the lack of familiarity of the pilots with the new navigation system installed in the aircraft, may have confused the pilots as to their real position in relation to the runway.

The following findings were identified:
- The condition of the runway at Cuenca airport, which at the time of the plane's landing was contaminated with water and slippery.
- The landing was made after a non-stabilized approach with a tailwind.
- During seven seconds, the crew continued the approach with an excessive rate of descent of 1,186 feet, 186 feet above the limit of 1,000 feet.
- The non-application of the Maximum Performance Landing procedure recommended by the aircraft manufacturer for landing on contaminated runways.
- The dispatch of the flight with 1,500 kg of fuel more than the amount of fuel usually used for this flight.
- Omission of the runway length calculation necessary to perform the landing using the braking efficiency information.
- The crew's decision to make the final approach with three red and one white lights, using the PAPI system, induced by the information in the Terminal Information document issued by the company, which authorized this procedure.
- The use of confusing terminology in the Terminal Information document, which used terms applicable to the Airbus fleet, instead of Embraer's.
- The crew's decision not to perform the thwarted approach maneuver after the maximum allowable vertical speed was exceeded and visibility was apparently limited after the minima were exceeded.
- Incorrect use of aircraft braking aids, in this case reverse braking aids
- The application of the emergency brake that inhibits the antiskid system.
- Lack of implementation of adequate management of crew resources, particularly within the cockpit.
- Lack of training in the use of tables for track distance calculation.
- In reference to landing conditions, the aircraft needed a runway length of 2,122 metres while the available distance was 1,900 metres.