Flight Operations

FLIGHT OPERATIONS

Featured Accident Report: Alone Across the Pond...

In August 2010, an experienced helicopter pilot lost his life in a little-known accident in the remote waters off the coast of Baffin Island, between Clyde River and Pond Inlet, Nunavut. Due to the far-flung location and the absence of passengers, the reality of our world did not make it a newsworthy event. Very few know about it, even in our own industry. Nevertheless, this report should be noticed by operators, crews and clients. What was planned as a long and ambitious ferry-flight quickly developed into a challenging trek in marginal weather, and resulted in the death of a pilot. We believe this report to be useful as a multi-facetted case-study for operators. It can be used to discuss many issues such as flight planning, weather, pressure, decision making, self-dispatch, flight duty times, fatigue, single-pilot resource management, survival equipment, flight following, search and rescue (SAR), maintenance documentation and possibly more. The following summary is based on TSB Final Report A10Q0133—Collision with Sea and does not include all issues covered in the extensive report. Therefore, we encourage our readers to read the complete report at their earliest opportunity. —Ed.

Summary
On August 16, 2010, a Bell 206L helicopter departed Clyde River, Nunavut, at 1609 Eastern Daylight Time on a VFR flight to Pond Inlet, Nunavut. Reduced visibility and low ceilings were forecast along the eastern coast of Baffin Island. The aircraft was equipped with a flight following device and was reported overdue at 1819. A search was initiated in the area of the last known position and wreckage was recovered from the surface of the sea on August 17, approximately 40 NM northwest of Clyde River. The helicopter was destroyed by impact forces; there was no fire. The pilot, the sole occupant of the helicopter, was not found. The accident occurred during daylight hours. No emergency locator transmitter (ELT) signal was detected by the SAR system.

route map

Route map

History of the Flight
The helicopter was being ferried from the island community of Qikiqtarjuaq (formerly known as Broughton Island), Nunavut, to Resolute Bay, Nunavut. The pilot selected a routing along the eastern coast of Baffin Island that would require fuel stops in Clyde River, Pond Inlet and Cape York (see Route map). A VFR flight plan was filed with an estimated time en route of 11 hr (9.5 hr flying with 3 stops of 30 min each). It was estimated that the pilot started his duty day at 0700. The filed departure time was 1000 which would have put the aircraft in Resolute Bay by 2100. This was just within the allowed 14-hr crew day and prior to sunset. Official sunset in Resolute Bay was after midnight. The SAR response time on the flight plan was for one hour after the estimated time of arrival in Resolute Bay.

The terrain along the eastern coast of Baffin Island rises dramatically from the sea and has many steep fjords. There are few locations to conduct a precautionary landing. Low cloud conditions would necessitate a routing along the coast line due to the steep terrain.

The pilot departed Qikiqtarjuaq at 1123 (one hour and 23 minutes past the filed departure time) and arrived in Clyde River at 1516 following two en route landings due to weather. The pilot departed for Pond Inlet at 1609. The last known position emitted from the flight following device was at 1639.

The pilot phoned his company’s dispatch, from Qikiqtarjuaq, at 0700 to discuss the weather. Due to the weather, the planned departure was delayed. The pilot phoned Arctic Radio at 0804 and received another weather briefing. At the time of this briefing the actual weather in Clyde River at 0700 was easterly winds at 7 kt, visibility 3/8 SM and a ceiling at zero feet AGL. The forecast for Clyde River valid through to 1500 was calling for visibility of 3 SM in light drizzle and mist with an overcast ceiling of 300 ft AGL; temporarily, the overcast ceiling was to go up to 1 200 ft AGL. The Pond Inlet forecast at the time of the briefing was calling for vertical ceilings of 100 ft AGL until 1200 but improving after that with a broken ceiling of 3 000 ft AGL.

The pilot contacted the customer in Resolute Bay at approximately 0900 and discussed satellite and infra-red imagery for the Clyde River area as well the actual weather in Clyde River and Pond Inlet. The 0800 weather was available at that time and for Clyde River the reported visibility was 1 and 1/8 SM with a ceiling at zero feet AGL. The 0800 weather for Pond Inlet was reported as visibility 9 SM with a ceiling at 7 600 ft AGL. There is no record that the pilot made further inquiries concerning the weather.

The Surface Analysis for 1400 on August 16, 2010, showed a large low pressure system centered over southern Hudson Bay. A weak surface trough extending northwards from this low into central Baffin Island resulted in a light easterly flow off Davis Strait and Baffin Bay onto the northeast coast of Baffin Island.

Satellite imagery indicated an extensive area of low cloud moving onshore in the light easterly flow all along the northeast coast of Baffin Island. Due to the topography of Baffin Island it is reasonable to conclude that the higher terrain to the west of Clyde River would have been obscured in the moist, onshore/upslope flow.

last route

Last route segment

The Aviation routine weather reports (METAR) in Clyde River were as follows:

  • At 1600: wind 050° True (T) at 4 kt, visibility 3 ½ SM, overcast ceiling at 200 ft AGL, with overcast layers to 7 600 ft AGL, temperature 7°C, dew point 7°C, and altimeter setting 29.91 in. of mercury (in. Hg).
  • At 1635: wind 040° T at 4 kt, visibility 2 ½ SM, overcast ceiling at 200 ft AGL, with overcast layers to 5 700 ft AGL, temperature 7°C, dew point 7°C, and altimeter setting 29.92 in. Hg.

The METARs in Pond Inlet were as follows:

  • At 1600: wind 250° T at 2 kt, visibility 15 SM with fog in the vicinity, few clouds at 500 ft AGL, few clouds at 2 000 ft AGL, broken ceiling at 6 800 ft AGL, temperature 7°C, dew point 6°C, and altimeter setting 29.93 in. Hg.
  • At 1700: wind 240° T at 5 kt, visibility 15 SM with fog in the vicinity, few clouds at 500 ft AGL, few clouds at 2 000 ft AGL, broken ceiling at 6 600 ft AGL, temperature 7°C, dew point 6°C, and altimeter setting 29.93 in. Hg.

The following terminal aerodrome forecasts were valid at the time of the crash (1500 on August 16, until 0300 on August 17):

Clyde River:

Wind 110° T at 3 kt, visibility 1 SM in light drizzle and mist, overcast ceiling at 200 ft AGL, temporarily for the period visibility 6 SM in mist, overcast ceiling at 800 ft AGL. Remarks: forecast based on automatic observations.

Pond Inlet:

Wind variable at 3 kt, visibility greater than 6 SM, few clouds at 300 ft AGL, scattered clouds at 2 000 ft AGL, broken ceiling at 6 000 ft AGL, temporarily for the period visibility greater than 6 SM in light rain, scattered cloud at 300 ft AGL, broken ceiling at 2 000 ft AGL, overcast cloud at 5 000 ft AGL.

The Graphical Area Forecast valid for the period closest to the time of the crash depicted an extensive area of low cloud over Clyde River with local visibility 1 SM in light drizzle and mist and ceilings of 300 ft AGL in coastal sections. No icing or turbulence hazards were forecast in the Clyde River area.

There are no weather reporting stations between Clyde River and Pond Inlet. Additionally, there were no pilot reports (PIREP) transmitted in the timeframe surrounding the crash.

The pilot was very experienced on type but was not instrument rated. This was the pilot's third season working with the company in the Arctic. The pilot was off duty the first two weeks of July, then flew from July 14 to August 3; the pilot was off duty from August 4 to August 7, and had been flying from August 8 to August 16, the day of the accident. The average duty day in August was 10 hr. At the time of the occurrence he had been on duty 9.5 hr. According to those reported dates and times, the TSB determined that the pilot had been operating within the flight and duty time requirements.

The helicopter was not equipped with a radar altimeter nor was it required to be. An immersion suit was on board but not worn by the pilot as it was recovered with the wreckage. A life jacket and life raft were part of the helicopter equipment on this flight, but neither was recovered. The life jacket was required to be manually activated after egress. It is not known if it was worn. The pilot's helmet was recovered.

 

Wreckage and impact information
The engine, most of the cockpit, and most of the tail section were not recovered. The fracture surfaces observed on the recovered sections were attributed to overstress as a result of water impact. The degree of helicopter break-up and damage to the recovered sections indicate an impact at a speed in excess of that associated with an emergency landing. The fracture surfaces exhibited characteristics that indicate the helicopter hit the water in forward flight with a left bank. The degree of bank could not be determined. No indications of pre-existing fractures were observed on the recovered wreckage.

recovered fuselage

Recovered fuselage

The left landing gear had separated along with its pop-out floats. The pop-out floats on the right skid were found deployed when the wreckage was recovered, and were keeping the wreckage afloat. There was insufficient wreckage recovered to rule out the possibility of a mechanical anomaly which could have triggered a caution light and an emergency landing. The fuel tank was recovered intact and was partially full. A fuel sample was sent for laboratory analysis and no anomalies were detected.

Spatial Disorientation
On the ground, spatial orientation is sensed by the combination of vision, muscle sense, and specialized organs in the inner ear, which sense linear and angular accelerations. Vision is the strongest of the orienting senses, and in visual flight, the pilot relies on regular visual references with the ground and horizon to control the aircraft attitude and altitude. If a pilot is in cloud, the visual reference to the ground and horizon is lost. As a result, the available cues (solely from the external forces on the body) often produce spatial disorientation in flight, because the pilot has a false impression of aircraft attitude and motion. Under these conditions, the pilot is completely dependent on the flight instruments and learned flying skills for control of the aircraft. Pilots that are not experienced with flying the aircraft solely with reference to instruments are particularly susceptible to spatial disorientation when they are confronted with no external visual attitude references. Flying over low contrast surfaces such as snow or water during overcast cloud conditions poses similar orientation challenges.

TSB Analysis
No indications of pre-existing fractures were observed on the recovered wreckage. The damage to the main rotor mast and transmission indicates the rotor drive train was rotating at the time of impact; the rate of rotation could not be determined. Fuel exhaustion and fuel quality were not considered contributing factors.

The helicopter would have been flying below 200 ft ASL given the overcast cloud layer and therefore the float inflation system should have been armed. The airframe damage suggests the helicopter was travelling above 52 kt and therefore it is unlikely that the floats were manually triggered. Given the speed at impact, it is unlikely that the pilot was faced with an in-flight mechanical anomaly which would have prompted an emergency landing.

The forces of the initial impact on the left landing gear were sufficient to tear the left skid and its flotation bags from the airframe. Even though the separation of the left landing gear caused the break of the left inflating lines and the venting of a large amount of nitrogen, sufficient volume was delivered to the right flotation bags to permit buoyancy of the remaining aircraft wreckage.

Although the ceiling was quite low on departure from Clyde River, the flight visibility was within the limitations for uncontrolled airspace. Based on the forecasts and actual weather, the pilot likely had an expectation that the weather would improve as he flew towards Pond Inlet. It is possible that the pilot departed with the intention to test the weather along the coast and return to Clyde River if the weather prevented safe transit to Pond Inlet.

The helicopter was crossing the mouth of a 15 NM-wide fjord when it went missing. The last known position was approximately one-third of the way across. It is unlikely the pilot would attempt the crossing if the far side was not visible. This would imply the visibility must have improved in the area of the fjord, at least when the crossing was initiated.

The following scenarios were considered by the TSB in an attempt to explain why the helicopter struck the sea surface:

  • There was insufficient wreckage to rule out the possibility of an in-flight mechanical anomaly (caution light). Due to the cloud ceiling the pilot would have been flying low-level over water. A minor distraction inside the cockpit could result in an inadvertent descent into the sea if the pilot was to lean forward and displace the cyclic while investigating a caution light or gauge display. This would result in a relatively high speed impact, which the wreckage also suggests.

  • If the weather worsened during the crossing, due to the low ceiling and low visibility described in the area forecast, then the pilot would be faced with a low-level flight over water with no visible land to assist spatial awareness. Flying over water under overcast clouds in rain and mist may have compromised the pilot's spatial orientation. The pilot was not instrument rated and would have been challenged to maintain helicopter control under these conditions. This may have resulted in one of the following:

    • Without a close crosscheck of altitude, an inadvertent descent could develop. Due to reduced visual cues in the deteriorating weather it may have gone unnoticed until it was too late to prevent impact with the sea surface. This would result in a relatively high speed impact, which the wreckage also suggests; or

    • Faced with deteriorating weather the pilot may have initiated a turn to the left to return to the closest shoreline. Without a strong background in instrument flying, it is possible that the pilot lost altitude and struck the sea while turning. This would result in a relatively high speed impact, which the wreckage also suggests.

Conclusion
The TSB said that there was insufficient factual information to conclusively state why the helicopter struck the sea surface. Complementary findings related to ELT, SAR and maintenance documentation are worth reading, as well as internal measures taken by the operator involved to learn from this event.

A few areas of concern are worth reflecting on, and these apply for single-pilot crew resource management (SCRM) scenarios. Clyde River is approximately a quarter of the distance to destination. Yet, already eight hours and nine minutes of the pilot’s duty day had been consumed by the time the flight departed Clyde River to continue the journey, and much of it included demanding flying in marginal weather over a hostile environment, while executing two en route stops to wait for weather to improve. Clearly, arrival to destination was no longer an option for that day.

The flight departed Clyde River at 1609 with an overcast ceiling of 200 ft (1600 and 1630 observations), visibility 3.5 SM decreasing to 2.5 SM and a zero spread between temperature and dew point. The ceiling and visibility required added concentration from the pilot who had just flown through marginal VFR weather in the previous leg of the flight.

Was the planning to destination overly ambitious? Were the three 30-min turnovers unrealistic? We encourage our readers to learn from this tragic accident.

Ever Heard of the Commercial Aviation Safety Team (CAST)?

Founded in 1998 in the United States (U.S.), CAST is a multi-national working group with an overarching goal of reducing fatality risk in world-wide commercial aviation. It applies an integrated, data-driven strategy to implement the most promising safety enhancements in our industry. Its original goal of reducing the commercial aviation fatality risk in the U.S. by 80 percent by 2008 was not only met, but surpassed; the rate was reduced by 83 percent. This was achieved by enabling a continuous improvement framework built on the proactive identification of current and future risks, developing mitigations as needed and monitoring the effectiveness of implemented actions. CAST has now challenged itself again, with a new goal of reducing the commercial aviation fatality risk in the U.S. by a further 50 percent from 2010 to 2025, while continuing to work with its international partners to reduce fatality risk in world-wide commercial aviation. Transport Canada is a member of CAST, and we invite you to learn more about it and use the safety resources found on the CAST Web site (www.cast-safety.org/), which includes a comprehensive list of excellent documents on runway safety, among others.

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