Transportation Safety Board wraps analysis of what caused Fond-du-Lac plane crash

The Transportation Safety Board of Canada (TSB) has wrapped its analysis into what caused a West Wind Aviation plane to crash near Fond-du-Lac, Sask., last year.

Work on a draft report has now begun, the TSB confirmed in an update earlier this month.

That means the agency's key work including testing equipment recovered from the wreckage,reconstructing the day's events and interviewing witnesses, the airline and government officials has been completed.

Here's a TSBchart showing how far along the report phase is in the overall investigation process:

One of West Wind Aviation's twin-turboprop planes, an ATR 42-320, crashed near the Fond-du-Lac airport shortly after takeoff on the evening of Dec. 13, 2017.

Ten people on board were seriously injured. One of them died in hospital two weeks after the crash.

• Plane in fatal Fond-du-Lac crash wasn't de-iced at airport before takeoff: TSB

• Experts slam 'woefully inadequate' spray bottle used for de-icing by West Wind Aviation

TheTSBhas already reported that the plane was not de-iced before takeoff, despite the aircraft still having ice on it from its previous flight.

The agency has not ruled whether that's what caused the crash.

Next steps

Once the draft report is completedit will be sent to groups affected by the report, including the airline.

"They then have the opportunity to dispute or correct information they believe to be incorrect," according to the TSB's website.

"The board considers all representations before approving the final report, which is subsequently released to the public."

Judge appointed to lawsuit

Several of the flight's passengers have sued West Wind Aviation and its parent company. They allegethe Saskatoon-based airline took "no appropriate steps" to de-ice the plane or runway and that the crew left the passengers "to fend for themselves in the chaos of the accident."

The Regina Court of Queen's Bench appointed Justice Robert Leurer to the case earlier this month.

• Passengers in Fond-du-Lac plane crash file class-action suit against airline

West Wind Aviation has yet to file a statement of defenceseven months after the suit was filed.

Tony Merchant, the lawyer representing the passengers, says that's not unusual.

"It is common for defendants not to file a defence in class actions until after the case has been certified," Merchant recently wrote CBC News.