Air transportation safety investigation A21C0038

The occurrence

At approximately 1548 Central Daylight Time on 25 April 2021, the Great Slave Helicopters 2018 Ltd. Airbus Helicopters AS 350 B2 (registration C-FYDA, serial number 4157) departed from a remote camp on Russell Island, Nunavut, on a day visual flight rules (VFR) flight to Resolute Bay Airport, Nunavut, located 87 nautical miles to the northeast. On board were the pilot, an aircraft maintenance engineer, and a biologist. The purpose of the flight was to return to Resolute Bay following 12 days spent conducting polar bear research for a client, given that poor weather was forecast in the area for the next several days.

At approximately 1633 Central Daylight Time, the helicopter impacted the snow-covered terrain on Griffith Island, Nunavut, approximately 12 nautical miles southwest of Resolute Bay Airport, on a near-reciprocal track to the intended route. The helicopter was destroyed, and a post-impact fire consumed much of the fuselage area. The emergency locator transmitter was destroyed during the impact sequence and did not transmit a distress signal. There were no survivors.

In addition to the circumstances that most likely led to the collision with terrain resulting from a loss of visual references in flat light and whiteout conditions, the investigation examined the factors that likely influenced the pilot’s decision-making process, the organizational defences in place at Great Slave Helicopters 2018 Ltd., and the regulatory environment.

Pilot decision making

The investigation found that the Transport Canada Aeronautical Information Manual provides very little guidance to operators and pilots with regards to strategies to recognize and cope with flat light and whiteout conditions. As a result, pilots may lack vital information to avoid or deal with inadvertent flight into instrument meteorological conditions (IIMC), increasing the risk of collision with terrain. In this occurrence, the pilot’s limited experience operating above the tree line during the winter and spring months likely lowered his perception of risk, influencing the decision to continue flight over featureless snow-covered terrain under overcast skies and poor visibility, conditions that were conducive to flat light and whiteout.

Furthermore, when engaged in remote operations, it is important for companies to implement measures to ensure an adequate level of supervision and to ensure that resources are in place to support pilot decision making. On the day of the occurrence, the pilot likely placed considerable weight on the client’s assessment that the weather was suitable for the return flight to Resolute Bay Airport, leading him to believe that additional weather information and/or a formal weather briefing from a source like NAV CANADA was not needed. As a result, safety margins were inadvertently reduced. If operators informally defer to, or encourage pilots to rely on, clients for flight-following activities, there is an increased risk that pilots will not receive sufficient supervision and decision-making support, such as relaying of weather information.

Defences against inadvertent flight into instrument meteorological conditions

The investigation determined that when the helicopter, which was being operated under day VFR, approached the highest elevation on Griffith Island, the uniformly snow-covered and featureless terrain, an overcast sky, and snow squalls likely created flat light and whiteout conditions that resulted in instrument meteorological conditions. Then, while the pilot was likely attempting to visually manoeuvre the helicopter in response to IIMC, an unintentional descent resulted in the helicopter impacting the terrain on a near-reciprocal track to the intended route.

Training

In order to make optimal decisions, pilots rely on their experience and training to build situational awareness by actively seeking out relevant cues, understanding those cues, and anticipating how those cues could affect the flight. However, in this occurrence, the pilot’s decision to depart was based on an incomplete understanding of the weather forecasted along the intended route. As a result, it is likely that his inaccurate mental model diminished the perceived importance of contingency planning for adverse weather.

The current regulations for day VFR helicopter operations focus primarily on defences designed to avoid IIMC. As such, there was no requirement for the occurrence pilot to be trained to recover from an IIMC encounter.

Because there is no requirement for commercial helicopter operators to ensure that pilots possess the skills necessary to recover from IIMC, the pilots and passengers who travel on VFR helicopters are at increased risk of collision with terrain following a loss of visual references.

The TSB has previously called for requirements for verification of proficiency in basic instrument flying skills for commercial helicopter pilots during annual pilot proficiency flight checks. However, Transport Canada (TC) has yet to implement sufficient measures in this regard. Therefore, the Board recommends that

Technology

Not only do the current regulations for day VFR helicopter operations not require pilots to be trained for IIMC recovery, they also do not require that aircraft used for these operations be equipped with technology that can assist with the avoidance of, and recovery from, IIMC. One of the most basic examples of this technology is flight instrumentation. In addition, several technological advances have emerged that can enhance pilot situational awareness and, therefore, assist in the reduction of IIMC accidents.

The TSB has previously attempted to address safety issues related to helicopter collision with terrain accidents, calling for increased requirements for flight instrumentation and other systems such as radar altimeters. To date, TC has not taken the measures needed to address these recommendations, which were issued more than 30 years ago. Therefore, the Board recommends that

Regulatory environment

Standard operating procedures

The investigation found that Great Slave Helicopters 2018 Ltd. adopted an approach consistent with the current regulations that relies on a pilot’s ability to avoid IIMC. As a result, the occurrence pilot lacked the skills to recover from IIMC. Standard operating procedures (SOPs) are widely accepted as a tool to enhance safety in multi-crew operations, and many of those same benefits apply equally to single-pilot operations. SOPs are particularly beneficial when a pilot lacks the knowledge or experience in a situation where a less-than-ideal course of action could reduce safety margins. However, single-pilot operations conducted under subparts 604, 702, 703, and 704 of the Canadian Aviation Regulations (CARs) are permitted without SOPs.

If SOPs for single-pilot operations are not required for CARs subparts 604, 702, 703, and 704 operators, those pilots may not be provided with vital decision-making support, increasing their potential to operate with levels of risk higher than necessary. Pilots and passengers who travel on those aircraft are consequently at increased risk of accident resulting from ineffective decision making and from cognitive workload in response to novel or unexpected situations. Therefore, the Board recommends that

Helicopter requirements for reduced-visibility operations in uncontrolled airspace

Moreover, many VFR helicopter and airplane operators are approved by TC to conduct reduced-visibility operations in uncontrolled airspace. The approval, granted as an operations specification, outlines requirements that operators must meet to carry out reduced-visibility operations in uncontrolled airspace. Some of these requirements are the same for helicopters and airplanes; however, the requirements for visibility limits, aircraft equipment, and pilot training are less strict for helicopters than for airplanes. This is despite the fact that the TSB has determined that helicopter accidents are more than twice as likely to involve a loss of visual reference than are airplane accidents.

If regulations continue to allow commercial helicopter operators with the applicable operations specification to conduct reduced-visibility operations in uncontrolled airspace at lower visibility, and with significantly fewer defences, than commercial airplane operators, these helicopter operators will continue to be at a greater risk of collision with terrain as a result of loss of visual references. Therefore, the Board recommends that

Safety management

Although not required by regulation, Great Slave Helicopters 2018 Ltd. implemented a system to manage safety—similar to a safety management system (SMS). An SMS allows companies to proactively manage safety through the timely identification of hazards that can reduce safety margins, and the implementation of defences to reduce those risks. The investigation determined that the risk management process at Great Slave Helicopters 2018 Ltd. overestimated the occurrence pilot’s level of operational readiness and the ability of existing defences to mitigate the risk posed by flat light and whiteout conditions. As a result, the occurrence pilot was dispatched to conduct remote operations, above the tree line, with insufficient safeguards to ensure adequate safety margins were maintained. If Transport Canada does not require all Canadian Aviation Regulations Part VII operators to have an SMS and does not evaluate these systems for effectiveness, there is a risk that operators will rely on inadequate processes to manage safety.

Safety action taken

Following the accident, Great Slave Helicopters 2018 Ltd. took several safety actions. These include a company-wide safety stand-down to ensure all personnel were safe to continue work; amendments to the SOPs following discussions with pilots about operating “in the white;” enhanced training and revised reference material related to overdue aircraft procedures; increased pilot recurrent training, with an emphasis placed on pilot decision making; several changes to its system for managing safety; the implementation of quarterly safety management meetings; and the creation a sub-committee that involves pilots and aircraft maintenance engineers in the review process of reports from its system used to manage safety.

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