Belém-Val de Cans-Júlio Cezar Ribeiro

The following findings were identified:
- The pilot took the risks inherent to that flight when he accepted to be the only crewmember on a night-time flight with an aircraft in which he lacked enough experience. It is therefore considered that the pilot was complacent when he accepted to fly the aircraft under those circumstances, taking the risks associated with the operation.
- The fact that the pilot made a phone call to his father, to tell that he was feeling insecure for conducting the flight, may be considered an indication that he was not confident, and this condition may have influenced negatively his operational performance during the descent procedure.
- It is possible that the motivation of the pilot in making a fast progress in his career contributed to his acceptance of the challenge to operate the flight, even if he was not feeling fully confident.
- It is possible that the characteristics related to the type of flight, regions, time of the day, in addition to the fact that the pilot was flying the aircraft alone for the first time, contributed to an unclear perception of the relevant elements around him, leading him to a mistaken comprehension, which resulted in the deterioration of his ability to foresee the events.
- The operational progress of the pilot in the company was expedited and, therefore, it is possible that for this reason he did not gather the necessary experience for conducting that type of flight.
- It is possible that the way the work was organized within the company, with designation of pilots not readapted in the aircraft for night-time flights without artificial horizon, and for takeoffs with an aircraft weight above the one prescribed in the manual contributed to the event that resulted in the accident.
- It is possible that the prioritization of the financial sector, in detriment of operational safety, contributed to the designation of a single pilot with short experience for transporting nine passengers.
- It is probable that the pilot, during the preparation of the aircraft for landing, allowed the its speed and power to drop to a value below the minima required for maintenance of level flight on the downwind leg.
- It is possible that the location of the runway in an isolated area of the Amazonian jungle region, without visual references in a night-time flight, contributed to the pilot’s difficulty maintaining a sustained flight.
- It is possible that the training done by the pilot in a shortened manner deprived him from the knowledge and other technical abilities necessary for flying the aircraft.
- The decisions of the company operation sector to designate a short-experienced pilot without a copilot for a night flight destined for an aerodrome located in a jungle region without visual reference with the terrain increased the risk of the operation. Therefore, the risk management process was probably inappropriate.
- It was the first time the pilot was flying the aircraft on a night-time flight without a copilot. Since he had only little experience in the aircraft, it is possible that his operational performance was hindered in the management of tasks, weakening his situational awareness.
- It was not possible to determine whether the company chose to dispense with the copilot on account of the need to transport a ninth passenger and, thus, did not consider in a conservative manner the prescription contained in the aircraft airworthiness certificate by designating just one pilot for the flight.

The following findings were identified:
a) The pilots had valid aeronautical medical certificates;
b) The pilots had valid technical qualification certificates;
c) The aircraft captain had qualification and enough experience for the flight in question;
d) The copilot was under training;
e) The aircraft had a valid airworthiness certificate;
f) The planning of the flight from SBSP to SBBE was done by the pilot in command, who took in consideration an aircraft with a full load of fuel;
g) The flight plan read that the fuel endurance was 7 hours and 30 minutes of flight, for an estimated elapse time of 5 hours and 40 minutes at FL230;
h) When the aircraft was passing over the city of Palmas, State of Tocantins, the pilots decided, in conjunction, to proceed non-stop to the destination, discarding the need to make an intermediate landing for refueling;
i) The aircraft was registered in the passenger transport category (TPP) and was engaged in the transport of a sick person;
j) The fuel quantity indicators and the fuel flow indicators of the aircraft were not showing dependable information;
k) The flight plan for the leg betwren SBSP and SBBE contained information of sick person transportation, but there was no sick person on board;
l) The aircraft made a ditching near the banks of Guajará Bay, at a distance of approximately 1,200 meters from the threshold of runway 06 of SBBE;
m) The passengers and crew were rescued by Brazilian Navy servicemen on duty on the Naval Base of Val de Cans;
n) One of the pilots and both passengers got out uninjured, while the other pilot suffered minor injuries; and
o) The aircraft sustained substantial damage.
Contributing factors:
Concerning the operation of the aircraft
a) Attitude – a contributor
The captain failed to comply with norms and procedures by accepting to fly an aircraft on his day of rest, even knowing that he was to start his on-call duty hours as soon as he landed in SBBE.
He also showed to be overconfident when he decided to fly directly from SBSP to SBBE, trusting the 7-hour fuel endurance of his aircraft and the fuel consumption information displayed by the instruments, even after identifying their malfunction. The pilot under training, in turn, was complacent by accepting and agreeing with the pilot-in-command’s decision, without questioning his calculations or motivations for flying direct to the destination.
b) Motivation – a contributor
The captain was eager to return to SBBE on that same day, because he was supposed to start his on-call duty hours in the air taxi company for which he worked.
c) Decision-making process – a contributor
The captain failed to comply with important aspects concerning the route conditions and aircraft instruments by making a decision to fly directly from SBSP to SBBE.
Psychosocial information
a) Communication – a contributor
There was lack of assertiveness on the part of the copilot since he did not question the captain’s calculations and/or motivations to fly non-stop, when he (the copilot) considered that making a stop for refueling would be safer.
b) External influence – a contributor
The involvement of the captain with activities of another company on that same day, in addition to events belonging to his private life, had influence on his decisions in the initial planning of the flight and during the flight en route.
Organizational information
a) Work organization – a contributor
The company delegated responsibility for the entire planning of the flight to the pilots. Therefore, there was not any interference on the part of the company in the crew’s work day and in the legs defined for the flight.
b) Organizational culture – a contributor
The fact that the company performed an operation for which it was not certified reflected the fragility of an organizational culture which allowed it to perform activities unfavorable to operational safety.
Operational Factor
Concerning the operation of the aircraft
a) Flight indiscipline – a contributor
On several occasions during the flight, the pilots failed to comply with the norms and regulations in force, such as the sections 91.167 and 91.205 of the RBHA 91, the Pilot Operating Handbook and FAA Approved Airplane Flight Manual, and the Lei do Aeronauta (Law of the Aeronaut, Law nº 7.183 of 5 April 1984).
b) Training – undetermined
Before the ditching, the pilot unlocked the rear door of the aircraft and, then, failed to instruct the passengers as to the opening of the emergency exit. This fact shows a probable deviation in the process of training previously received by the captain, since the procedure prescribed for the situation was to abandon the aircraft through the emergency exit, which had to be unlocked after the ditching.
c) Piloting judgment – a contributor
At the moment of their decision to proceed non-stop to the destination, there was an inappropriate evaluation on the part of the crew, because they did not consider the hourly consumption until that point, and the malfunction of the fuel capacity indicator did not allow them to know the exact amount of fuel remaining in the tanks.
d) Flight planning – a contributor
There was a mistake on the part of the captain relative to the planning of the flight, since, in addition to a total flight time of 5 hours and 40 minutes, he did not consider the fuel necessary to fly to an alternate airport plus 45 minutes of flight. The captain and the pilot under training made an inappropriate evaluation of the effects brought by the operational conditions along the flight route.

The following findings were identified:
- The LEFT MAIN LANDING GEAR ASSEMBLY (PN D23189000-19 and SN MN1700) collapsed, failing with 5,130 cycles after the last overhaul.
- A specific component (pin) of the assembly connecting the landing gear to the airframe, the AFT PIVOT PIN (P / N D61000, S / N 25), broke on account of fatigue, whose onset was facilitated by a machining process carried out in the pin section transition region.
- The ANAC-approved ATR72 Series Aircraft Maintenance Program of the TRIP Linhas Aéreas company read that the LEFT MAIN LANDING GEAR ASSEMBLY had to undergo overhaul every eight years or 18,000 cycles.
- On 27 February 2009, the PR-TTI landing gear was removed and, on 09 March 2009, was sent to be overhauled by the AV Indústria Aeronáutica Ltda. It had 31,684 cycles since new and 18,095 cycles since the last overhaul.
- AV Indústria Aeronáutica Ltda. was homologated for conducting such inspection, as specified in the List attached to the Addendum, Revision no. 11, dated 05 January 2009, and accepted by means of the Official Document no. 0173/2009-GGAC/SAR, issued by the Civil Aviation Authority.
- The AV Indústria Aeronáutica Ltda. company disassembled the legs of the landing gear, and outsourced some of the tasks for not possessing technical knowledge and/or appropriate machinery (necessary for the process of reconditioning the AFT PIVOT PIN (D61000 SN 25).
- Two of the three companies outsourced by AV Indústria Aeronáutica Ltda. were not homologated by the Civil Aviation Authority.
- The AV Indústria Aeronáutica Ltda. company conducted external audits of the three companies involved in the overhaul.
- The audits carried out by AV Indústria Aeronáutica Ltda. were not sufficient to identify that the contractors lacked qualified personnel, manuals and the machinery necessary to work with aeronautical products.
- The AV Indústria Aeronáutica Ltda. Technical Manager did not supervise the overhaul inspections and services performed by the contracted companies.
- The AFT PIVOT PIN (D61000 SN 25) is part of the assembly that connects the landing gear to the airframe.
- All revision tasks were described in the manuals of the manufacturer.
- The AFT PIVOT PIN (D61000 SN 25) failure-analysis report stated that the PRTTI aircraft left main landing gear collapsed on account of fatigue, whose onset was facilitated by a machining process carried out in the section transition region of the pin.
- The manufacturer's maintenance manual did not refer to any machining work in that region of the pin.
- In only one stage of the pin reconditioning process was it possible to observe that a machining task was required, namely, the Grinding of chromium.
- The lack of capacitation and training of the subcontractors’ professionals for handling aircraft material hindered the execution of an efficient maintenance work as prescribed by the manufacturer's manual, culminating in inadequate machining during the maintenance process.
- The lack of an effective process of supervision, both on the part of TRIP Linhas Aéreas and on the part of the other contractors and subcontractors allowed the existing maintenance services’ latent failures not to be checked and corrected, in a way capable of subsidizing, in an adequate and safe manner, the execution of the landing gear maintenance service.
- The process of supervision of the TRIP Linhas Aéreas and the AV Indústria Aeronáutica Ltda. companies by the Civil Aviation Authority, prescribed by specific legislation in force, was not enough to mitigate the latent conditions present in the accident in question.
- According to the technical opinion issued by the DCTA, the AFT PIVOT PIN (D61000 and SN 25) presented fracture surfaces with ± 45º inclination, as well as a flat area with multiple initiations, indicative of a fracture mechanism related to fatigue. In examinations of the external surface of the pin, in a region close to the fatigue fracture, cracks were observed that had initiated from scratches created by an inadequate maintenance machining process. In the region where the overload-related fracture occurred, it was also possible to identify that the machining process had modified the profile of the part in the section transition region, by producing a depression. Thus, it can be said that the AFT PIVOT PIN (D61000 and SN 25) of the PR-TTI left main gear broke on account of fatigue, whose onset was facilitated by an inadequate machining process that had been performed in the section transition region of the pin.

The following findings were identified:
- Weather conditions made it difficult for the crew to locate the runway;
- The crew failed to follow the emergency procedures and was unable to keep the aircraft level;
- The captain did not feather the left propeller, which resulted in increased drag and reduced aircraft speed;
- The engine maintenance did not meet the engine manufacturer's requirements;
- No technical overhaul of the left engine had been carried out despite the fact that the 12-year calendar limit set by the manufacturer had been exceeded;
- A nipple mounted on the left propeller governor was not intended for aeronautical use;
- The poor seal caused by the improper connection allowed the pressure to drop, resulting in a loss of power on the left engine;
- Poor organizational culture by the operator, which compromised the safety of the operation;
- The company did not have an effective supervision program;
- Poor judgment on part of the captain;
- Poor aircraft maintenance.

It was determined that both engines were running normally at impact and no technical anomalies were found on the aircraft and its equipments. Both pilots were properly licenced and experienced on this type of aircraft. At the time of the accident, weather conditions were poor with CB's, rains falls, severe turbulences, strong winds and probable windshear that may have been a contributing factor.

Failure of the second stage of the high pressure compressor disk in the left engine. Investigations were unable to determine the exact cause of the this failure, maybe following fatigue cracks or a construction defect. It was reported that the left engine accumulated 3,000 flying hours since the last compressor overhaul.

The following findings were identified:
- The total weight of the aircraft upon departure from Belém Airport was 650 kilos above MTOW,
- The cargo was not stowed in the cabin but simply stored on the floor,
- The left engine was not providing power at impact and the aircraft entered a left turn and then an uncontrolled descent until impact with the ground,
- Failure of the left engine due to the presence of an aluminum part obstructing the fuel pipe. Metallographic analyzes confirmed that this aluminum part likely came from a thread of the fuel pump,
- Complacency of the crew who failed to follow the published procedures of the operator.

It was determined that a fire of unknown origin erupted in flight, followed by several explosions. A that time, a load of ammunition was stored in several boxes in the cargo compartment.