Two Canadian companies have partnered to come up with a relatively simple fix for a design quirk on Cessna 206s that has been blamed for the loss of at least eight lives over the past 30 years. Coast Dog Aviation and Airworthiness Resources Corp., of Vancouver, teamed up to install a spring-loaded corner on the forward rear cargo door that allows it to be opened when the flaps are deployed. Without the mod, the door only opens about eight inches before hitting the flap and that also interferes with the routine opening of the rear door, effectively blocking the way out for passengers.
The door can be opened but it requires a multi-step process that is outlined on a placard above the door handle. Pilots are also supposed to brief passengers on its operation but by 1989 it became clear the door issue was a safety hazard. Cessna did offer a modification kit for the rear door latch mechanism that made it easier to open but it was not mandated. The most recent accident, in Canada’s Northwest Territories in 2018, killed three back-seat passengers. That prompted a 2019 AD from Transport Canada that turned the six-seat aircraft into a five-seater and required removal of a middle seat to allow back seat passengers an alternative escape route through the front doors.
“We were motivated after several accidents that cost lives,” said Dale Floyd, of Coast Dog Aviation. He and Airworthiness Resources owner Ron Strobl collaborated on the design and Stobl holds the resulting European and U.S. STCs and the alternative method of compliance for the Canadian AD, which the FAA is reviewing. In the Northwest Territories accident, the float-equipped plane flipped on landing on a lake and ended up submerged and inverted. The pilot and a front-seat passenger got out immediately and were quickly rescued. The pilot dove in but was unable to free the three passengers in the back. Those passengers had unhooked their seatbelts but couldn’t get the doors open. The Cessna latch kit had not been installed.
In a safety advisory, Canada’s Transportation Safety Board said the manufacturer and regulators had studied the problem in the early 2000s but essentially given up trying to find an effective solution. “Results of the studies indicated there were no suitable design changes that could feasibly be applied to the entire Cessna 206 fleet,” the TSB said. “By May 2008, the file was put on hold due to other priorities and the absence of a clear way forward.”