Brazil

The following factors were identified:
- Airport infrastructure – a contributor.
It was found that the irrigation pivot, at the point where the collision took place, was impairing the gauge of the approach surface as described in Ordinance 957/GC3, of 09JUL2015, which provided for restrictions on objects projected into the airspace that could adversely affect the safety or regularity of air operations.
- Piloting judgment – a contributor.
The final approach was carried out below the ideal approach ramp, allowing the collision against the pivot, located in the alignment of the runway.
- Perception – undetermined.
It is possible that the PIC, when approaching for the landing, did not notice the irrigation pivot and, therefore, collided with the obstacle.
- Flight planning – a contributor.
There was no prior coordination with the farm employees, in a timely manner so that the irrigation pivot could be repositioned to a safe location in relation to the flight trajectory on the final landing approach.

The following findings were identified:
- The approach was considered stabilized;
- The required landing distance of 6,431t (1,960m) was compatible for the operation, since the LDA of runway 32 at SBFI was 7,201ft (2,195m);
- There was no evidence of malfunction of the aircraft brake system that could have caused the runway excursion;
- At the time of landing, the runway was wet with a significant amount of water on the pavement;
- The estimated deceleration corresponded to what would be expected on a very wet runway (> 3mm of water) with hydroplaning of the tires at higher speeds;
- The friction and macrotexture measurements had normal parameters and did not contribute to the aircraft's poor deceleration;
- The characteristics of the precipitation over threshold 14 associated with the large variations in wind direction and intensity were consistent with the windshear phenomenon, resulting from a microburst;
- The PR-TLZ sensors did not detect the occurrence of windshear during the landing approach;
- A sudden increase in the calibrated speed that peaked at 32kt altered the aircraft's lift and, consequently, reduced the tires' grip on the ground, resulting in poor braking in the parts where the ground speed was lower;
- The speedbrakes were not extended during the run after landing, contrary to what was prevised in the AFM;
- The aircraft ran the full length of the runway, overpassed its limits and crashed into a ravine;
- There was a windshear alert issued about 30 seconds after the landing of the PRTLZ by an aircraft that was at the threshold 32;
- The aircraft had substantial damage; and
- The crewmembers and the passenger left unharmed.
Contributing factors:
- Control skills – undetermined
Despite the low contribution of the speedbrakes to the reduction of the landing distance, this device represents a deceleration resource through aerodynamic drag that should not be neglected, especially during landing on wet runways, and could have contributed to avoiding runway excursion.
- Adverse meteorological conditions – a contributor
The large variation in wind intensity peaked at 32 kt. This variation lasted 13 seconds and raised the indicated speed from 76 kt to 108 kt. Considering that the speed of 108 kt was very close to the VREF (111 KCAS), it can be stated that this phenomenon altered the aircraft's lift and, consequently, reduced the tires' grip on the ground, leading to poor braking.

Controlled flight into terrain.
Contributing factors.
- Attitude - contributed
The fact that the pilot continued the descent visually, not performing the instrument approach according to the IFR flight plan, denoted disregard of the real risks of this action. Thus, his attitude contributed to the inappropriate approach that culminated in the collision with the ground.
- Adverse weather conditions - contributed
Despite the aerodrome presenting ceiling and visibility conditions favorable for visual flight at the time of the accident, it was verified that there was dense fog covering the entire region near the impact site and, therefore, the IFR rules, which determined a minimum altitude of 5,000 ft, should have been observed.
- Emotional state - undetermined
Some events in the pilot's personal life were negatively affecting his emotional state. In addition, the pilot appeared to be more introspective in the period leading up to the accident.
Thus, it is possible that his performance was impaired due to his emotional state.
- External influences - undetermined
The pilot was possibly experiencing difficult events in his personal life. These events could have negatively affected his emotional state.
Thus, the pilot's way of thinking, reacting and performance at work may have been impacted by factors external to work.
- Motivation - undetermined
The pilot intended to return home because he would be celebrating his birthday and that of his stepdaughter.
The audio recording of the pilot's telephony with the GND-FL, shows that he insisted to accelerate his take-off, denoting a possible high motivation focused on fulfilling his eagerness to accomplish the flight. This condition may have influenced the flight performance.
- Decision making process - contributed
The choice to continue the descent without considering the IFR rules, based on an inadequate judgment of the meteorological conditions, revealed the pilot's difficulties to perceive, analyze, choose alternatives and act adequately in that situation.

The pilot intentionally changed his routing for Itapaci where the landing zone was not approved for flight operations. During the landing, the plane struck the ground before the planned zone and crashed. The pilot violated the rules established by the authority.

The pilot descended too low on approach to an umprepared terrain.
Contributing Factors:
- Attitude,
- Command application,
- Pilot judgment,
- Decision making process,
- Lack of adherence to regulations established by the authority of Brazilian civil aviation.

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.