Minas Gerais

The following factors were identified:
- Attention – undetermined.
It was found the possibility that the PT-ONJ aircraft crew had their attention (focused vision) on the runway at the expense of maintaining proper separation with the terrain on a visual approach.
- Piloting judgment – a contributor.
Regarding the approach to landing profile, there was an inadequate assessment of the aircraft's operating parameters, since the downwind leg was elongated by a significantly greater distance than that expected for a "Category B" aircraft in landing procedures under VFR.
- Memory – undetermined.
It is likely that, based on the experience of ten years of operation in a company governed by the RBAC 121, the PIC procedural memory has influenced the decisions made concerning the conduct of the aircraft. The habit of performing long final approaches in another type of operation may have activated his procedural memory, involving cognitive activities and motor skills, making the actions automated in relation to the profile performed in the accident.
- Flight planning – undetermined.
A possible non-use of the available aeronautical charts (CAP 9453 and WAC 3189), which were intended to meet the needs of visual flight, may have contributed to low situational awareness about the characteristics of the relief around the SNCT Aerodrome and the presence of the power grid that interfered with the aircraft's landing approach.

Following a wrong approach configuration on part of the crew, it was determined that the airplane landed about 600 metres from the runway end. In such conditions, the airplane could not be stopped within the remaining distance.
The following contributing factors were identified:
- Both pilots knew each other well and often flew together, thus it is possible that they over-relied on each other during the final phase of the flight,
- This over-confidence led the crew to neglect certain parameters related to the approach manoeuvre,
- Lack of crew coordination,
- Post-accident medical examinations revealed that the pilot-in-commands' (PF) lack of reaction to the pilot monitoring's (PM) warnings, and his impaired alertness, could indicate that he was suffering from the effects of alcohol and fatigue, reducing his performances,
- The pilots' decision to continue with the landing procedure despite an unstabilized approach characterized by inadequate situational awareness,
- Poor judgment on the part of the crew who failed to take the correct decision to initiate a go-around procedure.

Studies and research showed that the low deceleration of the aircraft and the limitation of the hydraulic pressure provided by the brake system were compatible with a slippery runway scenario. Thus, one inferred that the runway was contaminated, a condition that would reduce its coefficient of friction and impair the aircraft's braking performance, making it impossible to stop within the runway limits. On account of the mirroring condition of the runway in SSDK, it is possible that the crew had some difficulty perceiving, analyzing, choosing alternatives, and acting appropriately, given a possible inadequate judgment of the aircraft's landing performance on contaminated runways.

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.

Contributing factors:
- Control skills – undetermined
It is possible that, after inadvertent movement of the horizontal stabilizer, the crewmembers did not operate on the control switches of the secondary pitch trim system, since no other warning sound (Clacker) was recorded on the CVR recordings. The action prevised in the emergency procedures Pitch Trim Runaway or Failure, item 3, regarding trimming of the aircraft through the secondary system, possibly, was not performed. The performance of the crew may have been restricted only to the elevator control on the aircraft controls or to the control of the stabilizer associated with the primary trimming mode.
- Attitude – undetermined
The decision to make the flight without the proper functioning of the primary pitch trim and autopilot system may have been the result of the pilot's self-confidence because of the successful previous flight under similar operating conditions. Considering the hypothesis that the updated Shutdown Checklist, which should incorporate the Stabilizer Trim Backdrive Monitor - TEST, was not performed after the precrash flight, one could consider that there was a lack of adhesion to the aircraft operating procedures. Such an attitude could be associated with the pilot's self-confidence about the aircraft's operating routine, whose acquired experience could have given him the habit of ignoring some of the procedures deemed less important during the flight completion phase.
- Crew Resource Management – a contributor
Throughout the flight, there was an absence of verbalization and communication of the actions on the checklist. Similarly, in the face of the emergency situation of the horizontal stabilizer (Pitch Trim Runaway or Failure), no statements were identified regarding the actions required to manage this situation among the crew. These characteristics denote inefficiency in the use of human resources available for the aircraft operation.
- Training – undetermined
It is possible that the absence of a periodic training in simulator, especially the emergency Pitch Trim Runway or Failure, has affected the performance of the crew, as far as the CVR did not record statements related to the actions required by the abnormal condition experienced.
- Organizational culture – undetermined
The operator did not usually properly fill out the PT-WQH flight logbook. This condition evidenced the existence of informal rules regarding the monitoring of the operational conditions of the aircraft. In this context, it is possible that the history of failures related to the pitch trim system has not been registered.
- Piloting judgment – undetermined
Moments prior to takeoff, it was recorded in the CVR speeches related to the flight without the autopilot, possibly related to a failure or inoperativeness of the primary pitch trim system. The takeoff with a possible failure in the pitch trim system of the aircraft, showed an inadequate assessment of the risks involved in the operation under those conditions.
- Aircraft maintenance – undetermined
It was not possible to establish a link between the maintenance services performed on the aircraft in September 2015 and the events that resulted in the accident occurred on 10NOV2015. However, it was not ruled out that an incomplete crash survey was carried out in the pitch trim system of the aircraft, due to the lack of detail of the service orders.
- Decision-making process – a contributor
The sounds related to the test positions of the Rotary Test Switch have not been recorded in the CVR recording, so it is possible to conclude that the Warning Systems - Check item of the Cockpit Preparation Checklist has not been performed. The decision to perform the flight without the complete execution of all items of the Cockpit Preparation Checklist, prevented the correct verification of the primary longitudinal Trim system of the aircraft and reflected an inadequate judgment about the risks involved in that operation.
- Interpersonal relationship – undetermined
According to the CVR data, there was a possible rush of the crew to take-off, even though it was verified that the aircraft's pitch trim system did not work properly. It was not possible to determine if this rush was motivated by passengers’ pressure or self-imposed by the pilot.
- Support systems – undetermined
It is possible that the Pilots' Abbreviated Checklist - NORMAL PROCEDURES, aboard the aircraft, was outdated, without the incorporation of the Stabilizer Trim Backdrive Monitor - TEST procedure in the Shutdown Checklist. The possible completion of Shutdown Checklist with outdated procedures would have hampered the manufacturer's suggested verification for identification of abnormalities in the aircraft's pitch trim system.
- Managerial oversight – undetermined
The records and control of the operational check flights, both by the maintenance shop and by the operator, prevised in documentation issued by the manufacturer (SB650- 27-53 and ASL650-55-04) were not performed in an adequate manner, indicating possible weaknesses in the supervision of the maintenance activities.

It is believed that the accident was a consequence of a wrong takeoff configuration as the crew did not set the flaps properly.