Brazil

Contributing factors:
- Control skills - undetermined
The damage observed in the hot engine section components indicated the occurrence of an extrapolation of the ITT limits, which may have caused the melt observed in the blades of the compressor turbine. Thus, in view of the expected reactions of the engine during the use of the EPL, it is possible that there has been an inappropriate use of this resource and, consequently, an extrapolation of the engine limits, especially in relation to the temperature.
- Training - undetermined
The investigation of this accident identified issues related to the operation of the aircraft that could be related to the quality and/or frequency of emergency training with engine failure.
- Piloting judgment - undetermined
It is possible that the loss of lift produced by the flap retraction resulted in a sinking that prevented the plane from reaching the SWFN runway with the residual power that the engine still provided. In this case, an inadequate assessment of the effects of such action on the aircraft performance under those conditions would be characterized.
- Memory - undetermined
It is possible that the decisions made were the result of the pilot's difficulty in properly recalling the correct procedures for those circumstances, since these were actions to be memorized (memory items).

Despite the fact that the aircraft sustained significant damage, CENIPA classified the event as an 'Incident' and on August 5, 2018, reported that closed the investigation with no final report being issued.

At the beginning of the descent to Campo de Marte Airport, a failure occurred in the aircraft's propeller pitch control system, which tended to feather the engine.
The following findings were identified:
a) the pilots held valid Aeronautical Medical Certificates (CMA);
b) the PIC held valid Single-Engine Land Airplane (MNTE) and Airplane IFR Flight (IFRA) ratings;
c) the SIC held valid Single-Engine Land-Airplane (MNTE) and Multi-Engine LandAirplane (MLTE) ratings;
d) the pilots had qualification and experience in the type of flight;
e) the aircraft had a valid Airworthiness Certificate (CA);
f) the aircraft was within the prescribed weight and balance limits;
g) the records of the airframe, engine, and propeller logbooks were up to date;
h) the meteorological conditions were compatible with the conduction of the flight;
i) on 02Oct2017, a modification was made in the approved type-aircraft project;
j) on 06Mar2018, the engine of the aircraft was replaced with a rental engine, on account of damage caused by FOD;
k) the aircraft returned to the maintenance organization responsible for the engine replacement, due to recurrent episodes of Engine NP Warning Light illumination;
l) the maintenance organization inspected the powerplant, washed the compressor, and performed a pre-flight, after which the aircraft returned to operation;
m) the aircraft took off from SDAG, bound for SBMT;
n) between engine start-up and takeoff from SDAG, there were two drops of the propeller rotation (NP) to values below 950 RPM;
o) after taking off from SDAG, the aircraft climbed to, and maintained, FL145;
p) moments after the aircraft started descent, and upon reduction of the PCL, the propeller rotation began to drop quickly and continuously;
q) the adoption of the procedures prescribed for the situation “ENGINE NP - In flight, If propeller is below 1640” had no effect;
r) the NP dropped to a minimum value of 266 RPM;
s) the crew decision was to land in SDUB;
t) after the touchdown, a maneuver was performed aiming at exchanging speed for altitude, and deviation of the aircraft to a swampy area located in the left-hand side of the overshoot area;
u) in the functional tests of the engine performed after the occurrence, one verified normal operating conditions and full response to control demands;
v) upon examination of the propeller, and measurement of the beta ring distance, one verified that the ring displacement was outside the limits specified by the manufacturer;
w) it was not possible to identify whether such discrepancy had resulted from a maintenance procedure or from the impact during the emergency landing;
x) analysis of the propeller-governor revealed that the internal components were in operating condition;
y) the aircraft sustained substantial damage, and
z) the PIC suffered serious injuries, the SIC and two of the passengers were slightly injured, while the other six passengers were not hurt.

Contributing factors:
- Training – undetermined.
Even though the PIC had undergone simulator training less than a year before the occurrence, his difficulty perceiving the characteristics of the emergency experienced in order to frame it in accordance with his simulated practice suggests deficiencies in the processes related to qualification and training. The SIC, in turn, was not required to undergo that type of training, since the occurrence airplane had a Class-aircraft classification bestowed by the regulatory agency. The training and qualification process available to him in face of the circumstances may have contributed
to his lack of ability to recognize and participate in the management of the failure with due proficiency, when one also considers the selection of procedures and his assisting role in relation to the speeds and configuration of the aircraft.

- Instruction – a contributor.
As for the SIC, considering the fact that the aircraft classification did not require simulator sessions or other types of specific training, it was possible to note that he was not sufficiently familiar with emergencies and abnormal situations, something that prevented him from giving a better contribution to the management of the situation.

- Piloting judgment – a contributor.
There was inadequate assessment of the flight parameters on the final approach, something that made the landing in SDUB unfeasible, when one considers the 940 meters of available runway.

- Aircraft maintenance – undetermined.
During the measurement of the distance of the beta ring performed in the analysis of the propeller components, one verified that the displacement of the ring was outside the limits specified by the manufacturer. It was not possible to identify whether such displacement was due to a maintenance action or the result of a ring-assembly event at the time of propeller replacement. However, such discrepancy may have resulted from the impact of the propeller blades during the emergency landing. Furthermore, the aircraft was subject to inspection of the failure related to the ENGINE
NP warning light illumination prior to the accident. Given the fact that such illumination was intermittent, and the investigation could not identify the reasons for the warning, the aircraft was released for return to flight without in-depth investigation as to the root cause and possible implications of a failure related to the inadvertent drop in RPM.

- Memory – undetermined.
Although the PIC had undergone training in a class D aircraft-simulator certified by the manufacturer, it was not possible to verify the necessary association between the trained procedures and his performance in joining the traffic pattern and landing with a powerless aircraft in emergency. Furthermore, since the PIC frequently landed in the location selected for the emergency landing attempt, it is likely that he sought to match such emergency approach with those normally performed, in which he could count both on the “aerodynamic brake” condition with the propeller at IDLE and on the use of the reverse.

- Perception – a contributor / undetermined.
There was not adequate recognition, organization and understanding of the stimuli related to the condition of propeller feathering, which led to a lowering of the crew’s situational awareness.
Such reduction of the situational awareness made it difficult to assess the conditions under which the emergency could be managed, as the crew settled on the idea of landing in SDUB, without observing the condition of the airfield, meteorology, distance necessary for landing without control the engine, best glide speed, approach, and aircraft configuration.

- Decision-making process – a contributor / undetermined.
Since the first decisions made for identification of the emergency condition, it was not possible to verify the existence of a well-structured decision-making process contemplating appropriate assessment of the scenario and available alternatives. Objective aspects related to the SDUB runway, such as runway length and obstacles, the actual condition of the aircraft at that time, or contingencies, were not considered.

- Support systems – a contributor.
The Aircraft Manual and the QRH did not clearly contemplate the possibility of propeller feathering in flight, making it difficult for the pilots to identify the abnormal condition, and making it impossible for them to adopt appropriate and sufficient procedures for the correct management of the emergency. Considering the possibility that the application of the “ENGINE NP - In Flight”
emergency procedure prescribed by the QRH would not achieve the desired effect, there were no further instructions as to the next actions to be taken, leaving to the crew a possible
interpretation and selection of another procedure of the same publication.

- Managerial oversight – undetermined.
As for the maintenance workshop responsible for the tasks of engine replacement, together with adjustment of the propeller and its components: in the inspection at the request of the pilots after an event of ENGINE NP warning light illumination, the maintenance staff released the aircraft for return to operation. The investigation committee raised the possibility that the supervision of the services performed, by allowing the release of the aircraft, was not sufficient to guarantee mitigation of the risks related to the aircraft operation with the possibility of an intermittent recurrence of the failure.

Contributing factors:
- Attitude – a contributor
The pilot's failure to monitor the fueling showed a complacent attitude regarding the verification of conditions that could affect flight safety. Therefore, the lack of knowledge about the real fuel levels implied the insertion of wrong data and an intermediate landing to check the situation, after its identification.
- Training – undetermined
It is possible that the pilot's little familiarization with the aircraft emergency procedures delayed the identification of the situation and limited his possibilities of action.
- Insufficient pilot’s experience – undetermined
The pilot's little experience on the aircraft may have slowed his ability to recognize the emergency and to perform the actions described in the checklist efficiently.

The aircraft landed on the water with the landing gear in the down position.
Contributing factors:
- Attitude – a contributor
Failure to comply with the checklist during the pre-flight inspection and the flight itself favored the landing with inadequate configuration. This attitude may have been triggered by the pilot's confidence in his operational capability, because of his long experience in aviation.
- Flight indiscipline – a contributor
Failure to comply with the checklist indicated, in addition to the low level of situational awareness, a low level of concern for the safe conduction of the flight by failing to follow basic procedures set forth in the manufacturer's manuals and current regulations.
- Piloting judgement – a contributor
The pilot's choice not to use the checklist during the flight phases revealed an inadequate evaluation of parameters related to the operation of the aircraft. Improper compliance with the items in the Pre-Flight Inspection Sheet prevented the AMPHIB PUMP 1 and 2 circuit breakers from being rearmed.
- Aircraft maintenance – a contributor
After performing the test of landing gear extension and retraction by the emergency system, the AMPHIB PUMP 1 and 2 circuit breakers were not rearmed, being the aircraft delivered to fly in this condition. The setting recorded on the AIRSPEED switch of the landing gear position warning system computer demonstrated that the scheduled speed of 74kt was not in accordance with the recommended in the 9600-1A installation manual of Wipaire Inc. in its revision G.
- Memory – undetermined
The AMPHIB PUMP 1 and 2 circuit breakers were found disarmed after the occurrence, indicating that, after the completion of the maintenance service, the executor of the tasks probably forgot to comply with the procedures for reconfiguring the aircraft. In addition, it is possible that the pilot's automatism in relation to his way of carrying out the air operations, without the use of the checklist, has prevented the correct perception of the circuit breakers condition and the erroneous positioning of the landing gear.
- Perception – a contributor
The accomplishment of the landing on the water with the aircraft in inadequate configuration for the situation denotes a decrease in the level of situational awareness of the pilot, considering that the necessary factors and conditions for the safety of the operation were not observed.

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.