Simpson Air is improving training and won't fly its Cessna 206 aircraft on floats after one of its planes crash landed on a lake outside Fort Simpson, N.W.T., in August 2018.
The information is included in the Transportation Safety Board's safety investigation report into the accident, which killed three passengers — Geoffrey Dean, 33, from Castor, Alta., and Jean and Stewart Edelman, both 72, from Saskatoon.
The report was released Thursday.
The airline's float-equipped Cessna U206G was on a sightseeing flight between Fort Simpson's airport and Virginia Falls on Aug. 16, 2018, when its pilot lost control during a planned landing on Little Doctor Lake. The plane came to a rest in the lake, partially submerged and upside down.
The aircraft rollover was "relatively gentle," according to the investigation.
As the plane tumbled, water filled the cabin quickly because of a broken windshield. The pilot escaped through the pilot door's window, and the passenger seated in the front next to the pilot "grabbed the passenger ... behind the pilot and propelled her through the window," states the report.
The two were able to escape and climb up onto its floats. According to the report, a nearby boater rescued them within 15 minutes.
They escaped the crash with minor scrapes and bruises.
"Autopsy results showed that the remaining passengers were uninjured in the crash but had subsequently drowned," states the report.
They were unable to escape because the rear cargo doors were obstructed by the plane's wing flaps, and could only open approximately eight centimetres.
"There is a procedure to open the aft rear cargo door, but it is not easy to use, or simple and obvious to operate," states the report.
In this case we issued the safety advisory yet again, and it's up to Transport Canada to deal with it. - Gerrit Vermeer, Transportation Safety Board senior investigator
Gerrit Vermeer, a senior investigator for the Transportation Safety Board, says the Cessna involved in the crash was an old design, produced from 1963 and 1986. The company started making a new 206 model in the 1990s, and the U.S. Federal Aviation Administration approved the design of that plane.
Vermeer says previous to the 90s, Transport Canada accepted whatever FAA approved.
"But the new 206H Cessna model, Transport Canada had their own group of engineers looking at the design and said this rear double door doesn't meet design criteria," he said. "It's not simple and easy to use."
Transport Canada put new restrictions on that model of plane, but there are still 190 of the older model Cessnas still flying in Canada.
Vermeer said the Transportation Safety Board continues to raise these safety issues.
"In this case we issued the safety advisory yet again, and it's up to Transport Canada to deal with it, and to their credit, they are dealing with it."
He pointed to the fact that new laws are coming into force that will require flight crew to get better training, and that anybody on a float plane flying on or over water will have to wear a life vest.
Safety briefing incomplete, rubber mat blocked spaces
The report also found the plane's original floor coverings had been removed and replaced with rubber matting that was only fixed at one end. That meant once the plane overturned, the matting hung down, blocking the spaces between the seats.
"This could have made navigating those spaces difficult and could have added to confusion as passengers tried to make their way to emergency exits," states the report.
To further complicate things, the Transportation Safety Board found the passengers' safety briefing was incomplete. Although the passenger seated in the last row was shown how to manipulate the handles for the rear double cargo doors, "there was no mention in the briefing that flap deployment would block the forward rear cargo door, and no instructions were provided on how to overcome that situation," states the report.
The pilot had begun working for Simpson Air in June 2017 and began training to fly a Cessna U206G on floats one year later. She had successfully conducted six flights on this type of plane between Aug. 8 and 11, 2018, which involved six water takeoffs and landings.
Simpson Air decides to not operate plane
In response to the crash, Simpson Air has made the decision to no longer operate its Cessna 206 on floats.
The company also plans to give underwater egress training to all of its seasonal float-plane flight crew. Two employees had already completed the training.
Vermeer, with the Transportation Safety Board, said underwater egress training is known colloquially as "dunk-tank training."
"They take a frame mount and put some seats in it, you get in the thing and they dump you upside down in a swimming pool, and you have to get out of the air frame," he said.
Vermeer said flight crew who take it are statistically better prepared to get out of submerged aircraft, and help others escape as well.
Simpson Air is also bolstering the amount of experience it will require all new float-plane crew to have. They will be required to take a 50-hour bush float course, or have 500 hours of previous float experience.
Vermeer said it's an indication the company is taking the report's findings seriously.
"They've upped their standards in terms of their flight crew, so that's encouraging to see them responding."