Tuesday, January 31, 2012

Conditions below acceptable threshold in crash: Transportation Safety Board of Canada

Use of visual flight rules in adverse weather conditions was among the factors contributing to a deadly plane crash in Quebec more than a year ago.

On July 16, 2010, a float-equipped de Havilland Beaver operated by Air Saguenay (1980) Inc crashed into a mountain not far from Lake PĂ©ribonka, Quebec, notes a recent investigation report from the Transportation Safety Board of Canada (TSB).

Travelling from Lac des Quatre to Lac Margane, the plane was carrying one pilot and five passengers. Just a few minutes into the flight, the pilot reported his intentions to make a precautionary landing because of adverse weather conditions. The aircraft hit the wooded mountainside about 30 metres below its peak while flying straight and level.

The crash claimed the lives of the pilot and three passengers; the remaining passengers were injured, one seriously.

Federal investigators point to a number of contributing factors, including the following:

- the pilot took off in weather conditions that were below the minimum for visual flight rules (VFR) and continued the flight in those conditions;

- the pilot wound up in instrument meteorological conditions (IMC) after a late decision to make a precautionary landing, resulting in visual references being greatly reduced; and,

- the passenger at the rear of the aircraft was seated on a plastic chair and secured using anchors located on the floor of the aircraft (he was ejected from the plane on impact, diminishing his chances of survival).

The plane was equipped with an emergency locator transmitter (ELT), but its antenna located on the fuselage was torn off and the device itself was eventually consumed by fire. No ELT signal was received.

Asked if there is a need to change requirements around ELT positioning on aircraft, Maryse Durette, senior media relations advisor for Transport Canada, says that there are already obligations around installation and mounting.

"There will always exist the possibility of damage occurring that will render the unit inoperative, but steps are taken to minimize the chances," she adds.

Although low clouds were expected in the area, conditions on departure from Lac Margane at approximately 7:40 am were above the VFR minimum, notes the TSB report. The pilot intended to assess conditions en route and make a precautionary landing if unable to continue under VFR.

But between departing Lac Margane and the crash, there were a number of delays.

Within minutes of taking off, the pilot informed the base and the passengers that adverse weather conditions meant they would need to land. "The visibility at the front of the aircraft was nil. The ground could only be seen by looking directly downwards through the side windows, and it was frequently obstructed by the clouds," the TSB report notes. The crash occurred at 11:17 am.

Prolonged flying times "indicate considerable detours had to be made before the flight arrived at its destination," the report states. "It is quite likely that the weather conditions were below the thresholds prescribed by the Canadian Aviation Regulations," it adds.

"TSB data show that continuing a VFR flight in bad weather presents a serious safety threat," the report states.

Upon arriving at Lac des Quatre, there were no pressures of an operational nature forcing the pilot to expedite the return to the base on Lac Margane, the TSB reports. "Consequently, it is reasonable to believe that the pilot was convinced of being able to return to his base in the existing weather conditions, since the pilot had just flown over the area."

While the TSB report makes no recommendations for Transport Canada, Durette says the department will seek feedback from industry stakeholders around pilot decision-making (PDM) to determine what more may need to be done in this area.

As well, Transport Canada's website provides a PDM educational package that teaches concepts, principles and good practices, she adds.

The TSB also points to the value in educating passengers on the risks of flying in adverse weather conditions, as is done through the Circle of Safety Consumer Education Program south of the border. "It is better to ask questions about a flight and avoid a potential tragedy. This is good ‘risk management,' in which the passenger has a key role."

Transport Canada's "Weather to Fly" educational series seeks to create weather awareness as part of the flying environment. "Though primarily intended for members of the industry, it has useful information for passengers too," Durette says.

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