The Transportation Safety Board of Canada has released its investigation report into a 2023 landing gear collapse involving a British Aerospace Jetstream Model 3112 in Fort Simpson.
On April 14, 2023, a Jetstream aircraft operated by Northwestern Air Lease Ltd. was on a training flight with two pilots on board when the left main landing gear collapsed shortly after landing at Fort Simpson. The aircraft veered off the runway and came to rest in the grass. No injuries were reported, but the aircraft suffered significant damage to the left main landing gear, propeller, engine, wing tip, and belly cargo pod.
The TSB found that several cracks in the upper portion of the left main landing gear grew until the component failed during landing. The material was susceptible to stress corrosion cracking, a process in which tensile stress and a corrosive environment cause fractures to form and grow.
Although periodic inspections were required for the landing gear, the cracks on the occurrence aircraft were too small to be detected using standard inspection methods and went unnoticed.
Following the incident, the manufacturer and operators updated service information, including revisions to service bulletins, to emphasize corrosion protection and surface finish requirements for main landing gear components.
