Brazil

Contributing factors:
- Flight indiscipline – a contributor
The pilot failed to comply with the minimum fuel requirements laid down in the regulations, providing conditions for both engines to stop operating in flight, due to lack of fuel.
- Piloting judgment – a contributor
It was found in this flight an inadequate evaluation for certain parameters related to aircraft operation, particularly with regard to the influence of the chosen flight level on fuel consumption. This misjudgment led to the decision to proceed with the flight to the Aerodrome where it was intended to land, to the detriment of the more conservative option of finding a suitable place for an intermediate landing and a refueling, which led to the depletion of usable fuel in flight.
- Flight planning – a contributor
Inadequate flight preparation work, especially with regard to fuel calculation and cruise level selection, has degraded the safety level and also contributed to the actual accident.
- Decision-making process – undetermined
Difficulties in perceiving, analyzing, choosing alternatives, and acting appropriately due to inadequate judgment, may have resulted in poor assessment of flight parameters (available fuel, distance to destination, verified consumption, etc.), which may have favored the occurrence of lack of fuel failure.

Contributing factors:
- Adverse meteorological conditions - a contributor
At the moment of the impact of the aircraft, there was rain with rainfall potential of 25mm/h, covering the Paraty Bay region, and the horizontal visibility was 1,500m. Such horizontal visibility was below the minimum required for VFR landing and take-off operations. Since the SDTK aerodrome allowed only operations under VFR flight rules, the weather conditions proved to be impeding the operation within the required minimum safety limits.
- Decision-making process - a contributor
The weather conditions present in SDTK resulted in visibility restrictions that were impeding flight under VFR rules. In this context, the accomplishment of two attempts to approach and land procedures denoted an inadequate evaluation of the minimum conditions required for the operation at the Aerodrome.
- Disorientation - undetermined
The conditions of low visibility, of low height curve on the water, added to the pilot stress and also to the conditions of the wreckage, which did not show any fault that could have compromised the performance and/or controllability of the aircraft, indicate that the pilot most likely had a spatial disorientation that caused the loss of control of the aircraft.
- Emotional state - undetermined
Through the analysis of voice, speech and language parameters, variations in the emotional state of the pilot were identified that showed evidence of stress in the final moments of the flight. The pilot's high level of anxiety may have influenced his decision to make another attempt of landing even under adverse weather conditions and may have contributed to his disorientation.
- Tasks characteristics - undetermined
The operations in Paraty, RJ, demanded that pilots adapt to the routine of the operators, which was characteristic of the executive aviation. In addition, among operators, possibly because of the lack of minimum operational requirements in SDTK, the pilots who landed even in adverse weather conditions were recognized and valued by the others. Although there were no indications of external pressure on the part of the operator, these characteristics present in the operation in Paraty, RJ, may have favored the pilot's self-imposed pressure, leading him to operate with reduced safety margins.
- Visual illusions - undetermined
The flight conditions faced by the pilot favored the occurrence of the vestibular illusion due to the excess of "G" and the visual illusion of homogeneous terrain. Such illusions probably had, consequently, the pilot's sense that the bank angle was decreasing and that he was at a height above the real. These sensations may have led the pilot to erroneously correct the conditions he was experiencing. Thus, the great bank angle and the downward movement, observed at the moment of the impact of the aircraft, are probably a consequence of the phenomena of illusions.
- Work-group culture - a contributor
Among the members of the pilot group that performed routine flights to the region of Paraty, RJ, there was a culture of recognition and appreciation of those operating under adverse conditions, to the detriment of the requirements established for the VFR operation. These shared values promoted the adherence to informal practices and interfered in the perception and the adequate analysis of the risks present in the operation in SDTK.

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.

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 factors were identified:
- Application of the commands - contributed
There was no effective action on the aircraft controls during the final approach to avoid a brutal impact with the ground prior to the runway threshold.
- Adverse weather conditions - undetermined
It is possible that the aircraft was under the effect of the phenomenon known as windshear, which affected the approach profil and the subsequent impact with the ground short of runway.
- Pilot judgement - contributed
The risks of a possible windshear during the final approach were not adequately considered by the pilot. The decision to proceed for the landing, to the detriment of the alternative recommended by experts to perform a missed approach, proved decisive for the development of the accident.

Contributing factors
- Pilot judgment - undetermined
The absence of manuals and performance charts to guide the operation and actions based only on empirical knowledge about the aircraft may have taken to an inadequate evaluation of certain parameters related to its operation. In this case, the performance of the aircraft under conditions of weight, altitude and high temperatures may have provided its conduction with reduced margins of safety during takeoff that resulted in the on-screen accident.
- Flight planning - undetermined
The informality present in the field of experimental aviation, associated with the absence of support systems, may have resulted in an inadequacy in the work of flight preparation, particularly with regard to performance degradation in the face of adverse conditions (high weight, altitude and temperature), compromising the quality of the planning carried out, thus contributing to it being carried out a takeoff under marginal conditions.
- Project - undetermined
During the PR-ZRA assembly process, changes were incorporated into the Kit's original design that directly affected the airplane's take-off performance. Since the submission of documentation related to in-flight testing or performance graphics was not required by applicable law, it is possible that the experimental nature of the project has enabled the operation of the aircraft based on
empirical parameters and inadequate to their real capabilities.
- Support systems - undetermined
The absence of a support system, in the form of publications that allowed obtaining equipment performance data in order to carry out proper planning, added risk to operations and may have led to an attempt to take off under unsafe conditions.

Contributing factors:
- Application of commands - undetermined
It is possible that the pilot has not acted properly in the controls after touchdown to avoid a runway excursion.
- Flight indiscipline - contributed
Having landed on a non-approved runway, without justifiable reason, the crew member did not comply with the provisions of civil aviation regulations.
- Influence of the environment - undetermined
The wet and puddled runway may have affected directional control and aircraft braking performances during the landing roll.
- Pilot judgment - contributed
The crew member had not correctly assessed the risks involved in the operation in an unapproved runway, without justifiable reason. In addition, the pilot had no considering that the wet and puddle conditions of the runway could affect the directional control and braking performances of the aircraft.
- Decision-making process - contributed
The decision to land at an unapproved aerodrome, as well as having used a wet runway and the presence of puddles denoted an inadequate assessment of the risks present in the context. Failures related to decisions assumed by the pilot contributed to the occurrence insofar as they resulted in the entry of the aircraft into a critical condition, affecting its control.

Contributing factors:
- Application of commands – undetermined
Considering the hypothesis of spatial disorientation, of the disabling type, it is possible that the pilot has reached a situation of complete inability to operate correctly controls the aircraft in order to regain control of the flight.
- Attitude – undetermined
It is possible that the high subordination of the pilot to the requests of his boss has made it difficult for you to position yourself in relation to your limitation in flying at night and in instrument flight meteorological conditions.
- Disorientation – undetermined
Conditions favorable to disorientation, that is, the night flight over the sea, within clouds and manual operation, as well as the dynamics of the aircraft trajectory recorded by the radar, among other factors, make spatial disorientation the main hypothesis for the accident.
- Visual illusions – undetermined
It is also possible that the pilot suffered visual illusions when flying over the sea in night time. When not seeing the lighting on land, and being at night dark, with cloudiness, the pilot may have confused spatial references.
- Instruction – undetermined
It is possible that the lack of familiarity with the English language has made it difficult, in to some degree, knowledge of the resources, equipment and systems present in the aircraft, as well as in the instruction received in a flight simulator.