The unique scenario of damage to a plane wing from a tree strike likely contributed to a fatal accident in the Northwest Territories (N.W.T.) two years ago, the Transportation Safety Board of Canada (TSB) has revealed.
On Jan. 8, the TSB released its investigation report into the Aug. 22, 2013 accident that claimed the life of the pilot, the only person aboard the float plane. At about 6:50 p.m. that day, a Transwest Air DHC-3 turbine-powered Otter aircraft left Scott Lake, N.W.T. on a flight to Ivanhoe Lake, but did not arrive at its destination, the TSB report said. The company notified the Joint Rescue Coordination Centre, which dispatched a search and rescue aircraft. The following day, the wreckage of the plane was found on Aug. 23 in an unnamed lake between the take-off location and the destination.
Interestingly, the TSB found that damage to the plane from a prior tree strike and a number of stressors throughout the day had contributed to the accident. “The right wing was damaged [from] impact with several trees, and the damage was not evaluated or inspected by qualified personnel prior to the subsequent takeoff,” said a statement from the TSB. “The investigation also revealed that a number of stressors throughout the day disrupted the pilot’s processing of safety-critical information and likely contributed to an unsafe decision to depart and operate a damaged, uninspected aircraft.”
To enhance its operations, Transwest held discussions with its pilots concerning their responsibilities to remove themselves from flight duty if they do not feel fit to fly, the statement said. The company also issued a safety directive, outlining the company’s expectation of compliance with the Canadian Aviation Regulations and action to be taken if aircraft is damaged (refrain from flying until a licensed engineer has inspected and signed a release for that aircraft).
“If you have reason to suspect that an aircraft may have sustained physical damage that you cannot observe, enter a snag in the logbook and speak to an engineer immediately,” Transwest advised in the safety directive, issued on Sept. 30, 2013. “If you observe actual physical damage to an aircraft — even if you are not a pilot — you are required by [the Canadian Aviation Regulations] to ensure that the aircraft is grounded until it has been inspected and determined to be airworthy.”
The release of the report came two months after the TSB announced that it would conduct a safety issues investigation into Canadian air taxi operations to understand the risks that persist in the sector. The TSB has said that the study will engage industry, Transport Canada and other stakeholders to gain an understanding of the issues affecting air taxi operations and that the board may make recommendations to address any identified systemic deficiencies.