Campo de Marte AFB (São Paulo)

The accident was the consequence of the combination of the following factors:
- Attention – undetermined.
It is likely that the pilot has experienced a lowering of his attention in relation to the available information and the stimuli of that operational context in face of the adverse conditions faced.
- Attitude – a contributor.
It was concluded that there was no reaction to the warnings of proximity to the ground (Caution Terrain) and evasive action to avoid collision (Pull Up), a fact that revealed difficulties in thinking and acting in the face of an imminent collision condition, in which the aircraft was found.
- Adverse meteorological conditions – a contributor.
The clouds height and visibility conditions did not allow the flight to be conducted, up to SBMT, under VFR rules.
- Piloting judgment – a contributor.
The attempt to continue with the visual flight, without the minimum conditions for such, revealed an inadequate assessment, by the pilot, of parameters related to the operation of the aircraft, even though he was qualified to operate it.
- Perception – a contributor
The ability to recognize and project hazards related to continuing flight under visual rules, in marginal ceiling conditions and forward visibility, was impaired, resulting in reduced pilot situational awareness, probable geographic disorientation, and the phenomenon known as " tunnel vision''.
- Decision-making process – a contributor.
The impairment of the pilot's perception in relation to the risks related to the continuation of the flight in marginal safety conditions negatively affected his ability to perceive, analyze, choose alternatives and act appropriately due to inadequate judgments and the apparent fixation on keeping the flight under visual rules, which also contributed to this occurrence.

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:
- 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
- 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:
- Attention - undetermined
Moments before the accident, another aircraft successfully completed the landing at the Paraty aerodrome. It is possible that the pilot's attention was focused on this information, which indicated the possibility of landing, despite the critical conditions faced, leading him to take high risks to make the landing in critical conditions.
Also, the presence of a copilot not qualified to operate the aircraft may have influenced the pilot's cognitive processes, causing deconcentration or deviation of attention from the pilot.
- Attitude - contributed
Recurring attempts to make the landing indicated an excess of self-confidence on the part of the pilot, leading him to continue the flight to the Paraty aerodrome, even in adverse weather conditions.
The bold operational profile of the pilot, his past experience and the rules and values ​​adopted informally in the group of pilots are possible factors that influenced the development of this attitude of excessive self-confidence.
- Adverse weather conditions - contributed
On the day of the accident, the weather conditions were not favorable for visual flight at the Paraty aerodrome.
- Culture of the working group - contributed
Among the pilots who operated in the Paraty region, competitive behavior had been installed, valued by the social recognition attributed to those who managed to operate in critical conditions. Above all, landing under conditions adverse weather conditions in the region was considered a manifestation of proficiency and professional competence. The values ​​shared by that group of pilots favored the weakening of the collective perception about the present operational risks. The presence of other pilots who were also trying to land in the region on the day of the occurrence, as well as the landing made by one of these aircraft, moments before the accident, and also the accomplishment of two failed attempts of the PP-LMM aircraft, translates clear evidence of that behavior.
- Pilot forgetfulness - undetermined
The fact that the landing gear was not retracted during the second launch in the air indicated a failure, fueled by the possible forgetfulness of the crew, to perform the planned procedure. Maintaining the landing gear in the lowered position affected the aircraft's performance during the ascent, which may have contributed to the aircraft not reaching the height required to clear obstacles.
- Pilotage Judgment - undetermined
The possible decision not to retract the landing gear during the launch affected the aircraft's performance during the climb, which may have contributed to the aircraft not reaching the height necessary to clear the obstacles.
- Motivation - undetermined
The successful landing by the pilot of another aircraft, even under unfavorable conditions, may have increased the motivation of the pilot of the PP-LMM aircraft to complete the landing, in order to demonstrate his proficiency and professional competence.
- Perception - contributed
The occurrence of a collision with the ground, in controlled flight, indicated that the crew had a low level of situational awareness at the time of the occurrence. This inaccurate perception of the circumstances of the flight made it impossible to adopt the possible measures that could prevent the collision.
- Decision making process - contributed
The pilot chose to make two landing attempts at the Paraty aerodrome, despite adverse weather conditions, indicating an inaccurate assessment of the risks involved in the operation. This evaluation process may have been adversely affected by the competition behavior installed among the pilots. In this context, it is possible that the pilot based his decision only on the successful landing of another aircraft, a fact that limited his scope of evaluation.
- Organizational processes - undetermined
The PP-LMM aircraft was operated by a group of pilots, mostly composed of freelance professionals, who were informally managed by a hired pilot. Therefore, there was no formal system used by the operator to recruit, select, monitor and evaluate the performance of professionals. The failures related to the management of this process, possibly, caused inadequacies in the selection of pilots, in the crew scale, in untimely activations and, as in the case in question, in the choice of crew member not qualified to exercise function on board.

The following findings were identified:
- The crew considered the operation at Angra dos Reis Airport as unsafe, but operated the aircraft at that airport several times due to pressures from the aircraft's owner,
- The landing was completed with a tailwind component and a high aircraft weight, without considering the possibility to use runway 28, which demonstrated a poor assessment of the existing landing conditions,
- The relative short landing distance available, less than one km,
- The possible pressure exerted by the owner to carry out the flights, as well as the need to maintain the job or the professional image, may have contributed to the complacency behavior of the crew on the issues that lead to the operation of aircraft under conditions below acceptable safety standards,
- Poor flight planning,
- The relative low experience of the crew on this type of aircraft.

A possible loss of control during initial climb consecutive to a fuel imbalance. The following contributing factors were identified:
- Crew fatigue,
- Non-compliance with published procedures,
- Poor distribution of tasks prior to the flight and during the initial climb,
- Overconfidence on part of the crew,
- Poor flight preparation,
- Loss of situational awareness,
- Incorrect application of controls,
- The crew failed to follow the pre-takeoff checklist.

Double engine failure caused by a fuel exhaustion. It was determined that the crew did not prepare the flight according to procedures and took off with an insufficient fuel quantity on board.