Transport Canada's swift grounding of all flights from the company whose plane crashed in remote Fond-du-Lac, Sask., is a rare step according to several Canadian aviation experts, and the move could indicate a "glaring discrepancy" in the company's safety procedures.

On Friday, the federal airline regulator suspended the air operator certificate of Saskatoon-based West Wind Aviation.

The move came nine days after a 44-seat West Wind ATR turboprop plane, carrying 22 passengers and three crew members, crashed about 1.5 kilometres west of the Fond-du-Lac runway shortly after takeoff.

No one died in the crash, though six passengers and one of the pilots were seriously injured.

Loss of certificate a 'rare thing'

Transport Canada's inspection of an airline following a plane crash is routine. But its suspension of the company's certificate is not. The regulator said in its announcement that it grounded the airline because of "deficiencies in the company's operational control system."

Operational control systems track a number of things, including:

A plane's maintenance history.

The weight of a plane's luggage and cargo and how that weight is distributed throughout the plane.

Communication between pilots, dispatchers and other on-the-ground airline employees.

The field experience of the pilots and how many hours they worked before a flight that crashed.

"It's a rare thing" to suspend a certificate, said John McKenna, president of the Air Transport Association of Canada in an interview with CBC News.

Greg McConnell, a former veteran Transport Canada inspector for 25 years, estimated the regulator suspends fewer than 12 certificates a year, and does not do so lightly.

West Wind Aviation's air operator certificate has been suspended for an unknown amount of time. The company is located in Saskatoon, Sask. (CBC)

"The fact that Transportation Canada has taken action so quickly shows there was obviously a glaring discrepancy," said McConnell. "It's generally because there's not one little thing but a bunch of things that have completely gone awry."

Jock Williams, a retired Royal Canadian Air Force pilot and aviation expert, did not see Transport Canada's move as necessarily punitive, however.

"Nothing has been proven," he said, adding that it's unclear whether the deficiencies were accidental or made knowingly.

Whittling down the causes

The Transportation Safety Board of Canada (TSB) is an independent government body that investigates accidents and makes safety recommendations regarding aviation, rail, marine and pipelines. It's investigating the cause of the Dec. 13 crash.

The TSB has already ruled out engine failure, saying both engines were running until the turboprop hit the ground.

"When an aircraft only flies a mile after takeoff, there are only three or four possible explanations and none of them are particularly good," said Williams.

"One immediately thinks about frost or ice on the wings. They think of an aircraft overload, fuel contamination."

Length of suspension unknown

How long West Wind's suspension lasts depends on how quickly the company responds to and fixes the "deficiencies" flagged by Transport Canada.

"The suspension could be indefinite or it could be over in a matter of a few hours," said Williams.

The airstrip in Fond-du-Lac is at the northern end of the remote community. (Google Maps)

With no income coming to the company, "their motivation is going to be to take action to get that suspension terminated," Williams added.

On Saturday, West Wind's bookings page was directing customers to the website of its codeshare partner Transwest Air.

Prior incidents

West Wind said in a release Friday that it had already voluntarily grounded all of its flying operations before Transport Canada ordered it to.

It's not the first time the company clipped its own wings.

In September 2016, the company temporarily grounded its fleet because of what it called "potential administrative discrepancies" in its training records.

West Wind Aviation has been operating since 1983 and the company said in a recent statement it had never had an accident involving a serious injury until its flight went down in Fond-du-Lac earlier this month. (CBC)

In early 2015, the TSB investigated an incident of smoke in the cabin of the same West Wind turboprop that crashed in Fond-du-Lac. Investigators found that the smoke came from "counterfeit or unapproved" light bulbs installed on the plane.

"West Wind Aviation has been in existence since 1983 and until now has never had an accident involving a serious injury," the company said in a Saturday release.

Inspections have been reduced

McConnell, the former inspector, said Friday's suspension of West Wind "should be a lesson" to his former employer, Transport Canada. He said the regulator has gradually reduced the number of inspections it does of airlines.

"We used to visit every operator on an annual basis. That no longer happens," he said.

"That yearly requirement then went to a three-year requirement, then to a five-year requirement. Now operational visits are generally reactive after something bad happens."

A flight data recorder and cockpit voice recorder was recovered from the aircraft involved in the crash earlier this month. (Transportation Safety Board of Canada)

Neither West Wind Aviation nor Transport Canada responded to questions on Saturday.

The company said in a news release that it will work with Transport Canada to review its procedures and processes "to enhance the safety of our passengers and crews."

Athabasca Basin Development, a group of seven Northern Saskatchewan communities that owns 65 per cent of West Wind, declined to comment.