NORTHWEST TERRITORIES
Cannabis use by the pilot and and marginal weather conditions caused an Air Tindi flight to crash into a hill while on its way to Lutsel K'e from Yellowknife on Oct. 4, 2011, killing two Yellowknifers including the pilot, a Transportation Safety Board investigation has concluded.
Pilot Matthew Bromley, 28, and passenger Timothy Harris, 54, were killed when the Cessna Caravan 208B aircraft crashed on the Pethei Peninsula, a towering piece of land that rises 500 feet above Great Slave Lake shortly after 11:40 a.m. on Tuesday, Oct. 4, 2011, about 48 km from Lutsel K'e,
Matthew Bromley: Air Tindi had cannabis in his system during fatal flight.
Timothy Harris: NWT Power Corporation employee was the only passenger killed.
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The plane's two other passengers, Bernice Marlowe and Sheldon Catholique, both of Lutsel K'e, sustained serious injuries. A search and rescue effort initiated after the flight failed to arrive in Lutsel K'e located the wreckage. The two survivors were medevaced to Stanton Territorial Hospital and later to Edmonton the evening after the crash.
"This accident marked a very sad day for Air Tindi and those affected by this accident," stated Air Tindi President Sean Loutitt in a press release Wednesday.
"Air Tindi prides itself in the safe and reliable service it has offered to Canada's Northern communities over the past 25 years. We would like to express our condolences to the friends and family affected."
The flight was being conducted under visual flight rules, where the pilot relies on visual contact with the ground for navigation. This was within regulations at the time, however, had the flight been conducted under instrument flight rules, where the pilot relies on cockpit instruments rather than visible cues, the plane would have been "several thousand feet higher," said Jon Lee, western regional manager with the Transportation Safety Board (TSB).
"The actual what caused him to (fly at a low altitude) we'll never know, but as we said, the concentrations (of cannabis) were sufficient to have caused impairment in pilot performance and decision-making."
Both Bromley and Air Tindi had proper credentials to operate under instrument flight rules, although Bromley had only received his instrument rating two months before the crash after initially failing to achieve certification because of difficulties he experienced using the GPS system.
"Those visibilities and altitudes can be quite low," said Lee on the regulations surrounding flight under visual flight rules in uncontrolled airspace. "It's not the safest way to do it, but in Canada the regulations do allow for flying in low weather."
Whether to rely on visible cues or instruments is a decision left up to the pilot when planning a flight, said Lee.
"It is possible that the pilot, under the influence of cannabis, avoided the higher workload of (instrument flight rules) in (instrument weather conditions), choosing to remain visual for the trip to Lutsel K'e," states the TSB report in its analysis of the crash.
Toxicology report
The Transportation Safety Board could not definitively determine when Bromley had consumed cannabis before the flight, although postmortem tests showed he had THC levels of 50.1 nanograms per mililitre in his blood about 10 times more than what is considered to be threshold for impairment.
Peak THC concentration occurs between four and five days after use, and a single dose of cannabis can take up to 30 days to leave the user's system. Delta-9-THC -- the principal psychoactive ingredient found in marijuana, hashish, hash oil and certain other hemp products -- is first metabolized by the liver and THC compounds are then stored in fatty tissue. A blood plasma concentration of two to three nanograms per mililitre of blood indicates cannabis use within the previous six hours.
"Even allowing for a reasonable margin of error in the toxicology results, the amount of THC present in this occurrence is considerably greater than the threshold that resulted in degraded pilot performance in studies on the impairing effects of THC," states the TSB report.
Lee stressed that it is not up to the TSB to determine fault or criminal or civil liability in accidents. The mandate of the safety board is to investigate accidents for the purpose of advancing transportation safety. Witness testimony and testing conducted by the TSB may not be used in legal matters, he said.
Low-lying cloud conditions and scattered rain with temperatures of 6 C and the possibility of icing were recorded on the day of the accident by a routine aviation weather report at 11 a.m.
"Low cloud persisted for the entire flight, which was flown at low level so the pilot could maintain visual contact with the ground," stated the TSB report. "The descent during the last two minutes of the flight suggests that the ceiling had become lower."
"Because no effective evasive maneuvers were made before impact, it is likely that the crest of the Pethei Peninsula was obscured in fog, and not visible to the pilot. The application of increased engine power immediately before impact was likely made when the terrain in front of the aircraft suddenly became visible."
The Cessna Caravan was not equipped with a terrain awareness and warning system (TAWS). The plane initially hit the west side of the peninsula 20 feet above the face of a vertical cliff and 38 feet below the top of the embankment. The plane's landing gear was the first to make contact with terrain, followed by the belly of the cargo pod and the plane's propeller, states the report. All three were ripped from the aircraft followed by one of the plane's wings, said Lee.
The aircraft then continued uphill. Upon reaching the summit, it became airborne once more but the plane rolled and then finally came to rest upside down 477 feet down the eastern slope of the peninsula.
After the flight failed to arrive in Lutsel K'e at its scheduled arrival time of 11:45, an Air Tindi representative in Lutsel K'e alerted Air Tindi headquarters in Yellowknife. Two fixed-wing aircraft were dispatched to find the plane and at 2:20 p.m., a Havilland DHC-6 Twin Otter floatplane located the wreckage and landed nearby on Great Slave Lake. Personnel then hiked up the embankment to the crash site, where they arrived at about 3:30 p.m.
The two survivors were later shuttled from the crash site to the floatplane by helicopter and were medevaced to Yellowknife at 6 p.m.
Following recommendations made by the TSB, Air Tindi has since updated its drug and alcohol policy to include random drug and alcohol testing for pilots, maintenance engineers and dispatch personnel. However, the company has always had a zero-tolerance drug and alcohol policy and offered a confidential employee assistance program to all staff who were in need of support dealing with any issues that may affect their ability to perform their duties, Air Tindi stated in a press release.
All Air Tindi flights are now required to be flown under instrument flight rules unless a visual flight plan is approved by management.
Life-long Yellowknifer
Bromley, a life-long Yellowknifer, began working with Air Tindi in 2004 through its pilot-in-waiting program. He started as a ramp attendant in the hopes of moving on to a pilot position. In 2007, he began flying as a co-pilot, amassing 1,500 hours on a de Havilland DHC-6 Twin Otter, primarily flying under visual flight rules. He then began co-piloting a Beech King Air 200 aircraft in 2010, acquiring roughly 450 hours of flight time under instrument flight rules for that aircraft.
Bromley began training on Cessna 208 aircraft in February 2011 and completed certification under visual flight rules on that aircraft in March of that year before gaining his proficiency certification for operating a Cessna 208 under instrument flight rules in August 2011.
On the day of the crash, Bromley had just returned to work after three days off, states the TSB report. Before piloting the ill-fated flight from Yellowknife to Lutsel K'e, Bromley had piloted a flight from Fort Simpson to Yellowknife which departed at 8 a.m.
