Executive/Corporate/Business

The pilot's feathering of the incorrect propeller following a total loss of right engine power due to fuel starvation, which resulted from maintenance personnel's failure to reinstall the flapper valve in the right main fuel tank. Contributing to the accident was the pilot's impairment due to alcohol consumption.

Due to lack of evidences, the exact cause of the loss of control could not be determined.

The pilot's improper use of the trim, which created a cross-controlled situation and resulted in an aerodynamic stall during the attempted go-around.

The loss of right engine power on takeoff due to maintenance personnel's failure to properly tighten the crankcase through-studs during cylinder replacement, which resulted in crankshaft fracture. Also causal were the pilot's failure to feather the propeller on the right engine and his failure to maintain control of the twin-engine airplane while maneuvering to return to the airport.

The accident was the consequence of a black hole effect disorientation causing low-level manoeuvre into grass verge.
The following contributing factors were identified:
- Most of the runway 21 right edge lights were unserviceable at landing time.
- Inadequate Crew Resource Management during approach.

The failure of a spring inside the No. 2 brake's upper brake control valve and the fracture of the coupling subassembly of the No. 1 wheel speed sensor during landing, which resulted in the loss of braking action, and the pilot-in-command's (PIC) deactivation of the antiskid system even though there were no antiskid failure annunciations, which resulted in the rupture of the Nos. 1, 3, and 4 tires, further loss of braking action, and subsequent landing overrun. Contributing to accident were the PIC's improper landing flare, which resulted in landing several hundred feet beyond the aiming point marking, and his unsuccessful attempts to deploy the thrust reversers for reasons that could not be determined because postaccident operational testing did not reveal any anomalies that would have precluded normal operation. Contributing to the passenger's injury was his leaving his seat intentionally while the airplane was in motion.

A failure of the right engine magneto distributor drive gears, which resulted in a total loss of engine power during takeoff. Contributing to the accident was the operator's failure to inspect and maintain the magnetos in accordance with the engine manufacturer's specifications.

The following factors were identified:
- Considering the pronounced angle formed between the trajectory of the aircraft and the terrain, as well as the calculated speed (which by far exceeded the aircraft operating limit) moments before the impact, it is possible to infer that, from the moment the aircraft disappeared in the clouds, it could only have reached such speed and flown that trajectory if it had climbed considerably, to the point of being detected by the radar. Such condition presented by the aircraft may have been the result of an exaggerated application of controls.
- The making of an approach with a profile different from the one prescribed shows lack of adherence to procedures, which, in this case, may have been influenced by the self-confidence of the pilot on his piloting ability, given his prior experiences.
- Despite the lack of pressure on the part of the passengers to force compliance with the agenda, it is a known fact that this type of routine creates in the crew a self-pressure, most of the time unconscious, for accomplishing the flight schedule on account of the commitments undertaken by the candidate in campaign, and, therefore, the specific characteristics of this type of flight pose demands in terms of performance that may have influenced the pilots to operate with reduced safety margins.
- The meteorological conditions were close to the safety minimums for the approach and below the minimums for the circle-to-land procedure prescribed in the ECHO 1 approach. However, such conditions, by themselves, would not represent risk for the operation, if the profile of the ECHO 1 procedure was performed in accordance with the parameters established in the aeronautical publications and the flight parameters defined by the aircraft manufacturer. Upon verifying that the above mentioned parameters were not complied with, one observes that the meteorological conditions became a complicating factor for flying the aircraft, rendering it difficult to be stabilized on the final approach, and a go-around became necessary, as a result.
- In the scenario of the aircraft collision with the ground, there were aspects favorable to the occurrence of spatial disorientation, such as: reduction of the visibility on account of meteorological conditions, stress and workload increase due to the missed approach procedure, maneuvers with a G-load above 1.15G, and a possible loss of situational awareness. The large pitch-down angle, the high speed, and the power developed by the engines at the moment of impact are also evidence compatible with incapacitating disorientation, and point towards a contribution of this factor.
- The integration between the pilots may have been hindered by their little experience working together as one crew, and also by their different training background. In addition, the personal characteristics of the captain, as a more impositive and confident person, in contrast with the more passive posture of the copilot, may also have hampered the crew dynamics in the management of the flight.
- In the seven days preceding the day of the accident, the crew was in conformity with the Law 7183 of 5 April 1984 in relation to both duty time and rest periods. However, the analysis of copilot’s voice, speech, and language indicated compatibility with fatigue and somnolence, something that may have contributed to the degradation of the crew’s performance.
- Their lack of training of missed approach procedures in CE 560XLS+ aircraft may have demanded from the crew a higher cognitive effort in relation to the conditions required for the aircraft model, since they possibly did not have conditioned behaviors for controlling the flight and that could otherwise provide them with more agility with regard to the cockpit actions. Thus, they probably missed the skills, knowledge, and attitudes that would allow them to more adequately perform their activities in that operational context.
- Even though Santos Radio reported, in the first contact with the aircraft, that the aerodrome was operating IFR, the messages transmitted to the aircraft did not include the conditions of ceiling, visibility, and SIGMET information (ICA 100-37). This may have contributed to reducing the crew’s situational awareness, since the last information accessed by them was probably the 11:00 UTC SBST METAR, which reported VMC conditions for operation in the aerodrome. Thus, the pilots may have built a mental model of unreal SBST meteorological conditions more favorable to the operation.
- After coordination of the descent, the PR-AFA aircraft made a left turn and, for an unknown reason, deviated from the W6-airway profile, reporting six positions that were not compatible with the real flight path until the moment it started a final approach. This approach was different from the trajectory of the final approach defined for the ECHO 1 procedure, and was flown with speed parameters different from those recommended by the aircraft manufacturer. These aspects reduced the chances of the aircraft to align with the final approach in a stabilized manner. The fact that the aircraft made a low pass over the runway and then a left turn at low altitude in weather conditions below the minimum established in the circle-to-land procedure instead of performing the profile prescribed in the ECHO 1 approach chart also resulted in risks to the operation, and created conditions which were conducive to spatial disorientation.
- Since the captain had already conducted FMS visual approaches on other occasions, his acquired work-memory may have strengthened his confidence in performing the procedure again, even though in another scenario, on account of the human being tendency to rely on previous successful experiences.
- A poor perception on the part of the pilots relative to the real meteorological conditions on the approach may have compromised their level of situational awareness, thus leading the aircraft to a condition of operation below the safe minimums.
- The TAF/GAMET weather prognostics with validity up to 12:00 UTC, and available to the crew at the time the flight plan was filed at the AIS-RJ, indicated a possibility of degradation of the ceiling and visibility parameters on account of rain associated with mist, encompassing the duration of the aforementioned flight, especially in the area of SBST. The 11:00 UTC satellite image and the SIGMET valid from 10:30 UTC to 13:30 UTC, also showed an active cold front in the Southeast with stratiform cloud layers over SBST and a forecast of convective cells with northeasterly movement at an average speed of 12kt. Despite the availability of such information, the crew may not have made a more accurate analysis showing the swift deterioration of the weather conditions in the period between their takeoff from SBRJ and the approach to SBST, and thus may have failed to plan their conduct of the flight in accordance with the weather conditions forecast by the meteorological services.
- Despite having the C560 qualification required to operate the CE 560XLS+aircraft, the pilots were not checked by the employers as to their previous experience on this kind of equipment, or as to the need of transition training and/or specific formation to fly the PRAFA aircraft. The adoption of a formal process for the recruitment, selection, monitoring and evaluation of the performance of the professionals could have identified their training needs for that type of aircraft.
- Although the RBAC 61 requires pilots to undergo flight instruction and proficiency checks to switch between models of the CE 560XL family, the need of specific training was only clarified on 4 July 2014, with the publication of the ANAC Supplementary Instruction (IS 61-004, Revision A). Until that date, this need could only be determined by means of consultation of the FSB Report, made available only on the FAA website. In this context, the PR-AFA pilots would only be evaluated on the CE 560XLS+ aircraft on the occasion of their type revalidation, which would take place shortly before the expiration date of their C560 qualifications, which were valid until October 2014 (captain), and May 2015 (copilot). The fact that there was a qualification (C560) that was shared for the operation of C560 Citation V, C560 Encore, C560 Encore+, CE 560XL, CE 560XLS, or CE 560XLS + aircraft was not enough to make the DCERTA system refuse flight plans filed by pilots who lacked proper training to operate one of the aforementioned aircraft models. The RBAC 67 contained physical and mental health requirements which were not clear, inducing physicians to resort to other publications for guidance and support of their decisions and judgments relative to the civil aviation personnel. The absence of clear requirements to be adopted as the acceptable minimum for the exercise of the air activity, led the physicians responsible for judging the pilots’ health inspections’ to use their own discretion on the subject, opening gaps that could allow professionals not fully qualified to perform functions in flight below the minimum acceptable safety levels.
- Considering the possibility that the captain accumulated tasks as a result of a possible difficulty of the copilot in assisting him at the beginning of the missed approach procedure, such accumulation may have exceeded his ability to deal with the tasks, leading him to committing piloting errors and/or experiencing spatial disorientation.

Due to the absence of any flight data recorder, investigations were unable to determine with certainty the exact cause and circumstances of the accident.