Landing (descent or approach)

The following contributing factors were identified:
- The flight crew continued the descent in instrument meteorological conditions without confirming their position.
- The flight crew’s assessment of their position was incorrect and they had lost situational awareness
- The flight crew deprived themselves of the “Caution” and “Warning” alerts that would have sounded about 20 sec and about 10 sec respectively before the collision, by not deactivating the EGPWS Terrain Inhibit prior to departure from Woitape.

The accident resulted from the combination of immediate triggers and failures in the aeronautical system's defenses, including:
- Prevailing weather conditions at the scene of the accident;
- Pilot-in-command experienced difficulties in managing aircraft control and flight path during an instrument approach;
- The probability of overload of work of the pilot in command as a result of the operational demands presented by the situation;
- The execution of the operation by a single pilot (single pilot operation), taking into account the age of the pilot; and
- Deficiencies in pilot-in-command certification denying the value of CE-6 as a defense barrier for the aeronautical system (CE-6 is a Critical Element of ICAO Annex 19 regarding responsibilities in issuing licenses).

The pilot's failure to maintain sufficient clearance from trees during the single engine and landing approach. Contributing to the accident was the loss of power in the left engine due to an improperly installed rubber boot that became dislodged and was then partially sucked into the fuel injector servo, which caused an excessively rich fuel-air mixture that would not support combustion.

The rupture of two teeth of the sprocket of the control cylinder of the left main landing gear caused the cylinder to be locked and thus caused the mechanical system to extend the landing gear. This blockage prevented the complete extension and locking of the landing gear. This rupture and other damage to the two main landing gear actuators was probably the result of improper installation of the toothed gear and / or improper adjustment of the assembly.

The flight instructor's delayed decision to abort the simulated engine out maneuver, his failure to unfeather the propeller before restoring engine power, and his inadequate airspeed management, which led to an aerodynamic stall at low altitude.

The pilot's failure to maintain adequate airspeed and exceedance of the critical angle of attack during a go-around with a tailwind condition, which resulted in an aerodynamic stall. A contributing factor to the accident was the pilot's decision to continue the approach with opposing traffic.

The probable cause of this accident has been determined as a lack of situational awareness resulting in a stalled condition and loss of control while attempting to remedy a fuel exhaustion condition at a very low altitude.
Contributing factors:
- The pilot’s incorrect fuel calculations which resulted in fuel exhaustion to both engines.
- Stalled aircraft.
- Loss of situational awareness.

Findings as to causes and contributing factors:
1. The captain commenced the flight with only a single headset on board, thereby preventing a shared situational awareness among the crew.
2. It is likely that the weather at the time of both approaches was such that the captain could not see the required visual references to ensure a safe landing.
3. The first officer was focused on locating the runway and was unaware of the captain’s actions during the descent.
4. For undetermined reasons, the captain initiated a steep descent 0.56 nautical mile from the threshold, which went uncorrected until a point from which it was too late to recover.
5. The aircraft contacted a road 0.25 nautical mile short of the runway and struck terrain.
6. The paramedic was not wearing a seatbelt and was not restrained during the impact sequence.
Findings as to risk:
1. If cockpit data recordings are not available to an investigation, then the identification and communication of safety deficiencies to advance transportation safety may be precluded.
2. If crew members are unable to communicate effectively, then they are less likely to anticipate and coordinate their actions, which could jeopardize the safety of flight.
3. If crew resource management training is not provided, used and continuously fostered, then there is a risk that pilots will be unprepared to avoid or mitigate crew errors encountered during flight.
4. If an actual weight and balance cannot be determined, then the aircraft may be operating outside of its approved limits, which could affect the aircraft’s performance characteristics.
5. If pre-computed weight and balance forms do not include standard items, then it increases the likelihood of omissions in weight and balance calculations, which increases the risk of inadvertently overloading or incorrectly loading the aircraft.
6. If organizations carry out a maintenance task that they consider to be elementary work and the task is not approved as an elementary work task, then there is a risk that the aircraft will not conform to its type design, which could jeopardize the safety of flight.
7. If individuals are performing maintenance tasks for which they have not received approved training, then there is a risk that the task will not be performed in accordance with the manufacturer’s instructions.
8. If components are not installed in accordance with the manufacturer’s instructions, then occupants are at a greater risk of injury or death during an incident or accident if these components are not properly secured.
9. If organizations do not record when maintenance is carried out, then the proper completion of tasks cannot be confirmed, and there is a risk that the aircraft will not conform to its type design, which could jeopardize the safety of flight.
10. If an aircraft is modified without regulatory approval and without supporting documentation, then the aircraft is not in compliance with all applicable standards of airworthiness, which could jeopardize the safety of flight.
11. If an operator undertakes unapproved changes to a supplemental type certificate, then there is a risk that the aircraft will not be airworthy, which could jeopardize the safety of flight.
12. If organizations do not use modern safety management practices, then there is an increased risk that hazards will not be identified and risks mitigated.
13. If Transport Canada does not adopt a balanced approach that combines thorough inspections for compliance with audits of safety management processes, unsafe operating practices may not be identified, thereby increasing the risk of accidents.
14. If organizations contract aviation companies to provide a service with which the organizations are not familiar, then there is an increased risk that safety deficiencies will go unnoticed, which could jeopardize the safety of the organizations’ employees.
15. If passengers are not provided with a regular safety briefing, then there is an increased risk that they will not use the available safety equipment or be able to perform necessary emergency functions in a timely manner to avoid injury or death.
16. If passengers are not properly restrained, then there is an increased risk of injuries and death to those passengers and the other occupants in the event of an accident.
17. If carry-on baggage, equipment or cargo is not restrained, then occupants are at a greater risk of injury or death if these items become projectiles in a crash.
18. If carry-on baggage, equipment or cargo is not restrained, then there is an increased risk that the occupants’ access to normal and emergency exits, and to safety equipment, will be completely or partially blocked.
19. If pilots continue an approach below published minimum descent altitudes without seeing the required visual references, then there is a risk of collision with terrain and/or obstacles.
20. If current charts and databases are not used, then navigational accuracy and obstacle avoidance cannot be assured.
21. If GPS (global positioning system) approaches are conducted without the approved Operations Specification, then there is a risk that the pilot’s training and knowledge will be inadequate to safely conduct the approach.
22. If medical symptoms/conditions are not reported to Transport Canada, then it negates some of the safety benefit of examinations and increases the risk that pilots will continue to fly with a medical condition that poses a risk to safety.
Other findings:
1. The pilot who installed the air ambulance system did not have approved training, nor was the pilot approved to carry out elementary work.
2. Atlantic Charters was not approved to install the air ambulance system as an elementary work task.
3. Atlantic Charters’ pre-computed weight and balance form did not include a line item to indicate nacelle fuel.
4. The semi-annual safety training offered to paramedics in lieu of safety briefings prior to flights did not meet regulatory requirements.

The aircraft’s left main landing gear failed as a result of stress corrosion cracking in the forward pintle housing, at the top of the left landing gear cylinder. The landing gear material is known to be susceptible to stress corrosion cracking. The investigation determined that a design solution implemented by the aircraft manufacturer following the 2012 accident, which was intended to prevent stress corrosion cracking, had not met its original design intent.