TSB stresses oversight, independent inspections and post-maintenance checks for employers
A recent Transportation Safety Board of Canada (TSB) investigation into a fatal floatplane accident in Quebec is raising fresh concerns about maintenance oversight, independent inspections, and pre-flight verification of flight controls — all with direct implications for Canadian employers managing aviation operations and remote work access.
Maintenance error reversed aileron controls
On 2 May 2025, a float-equipped De Havilland DHC‑2 Beaver operated by ETA Aviation & César Camp du Nord Inc. overturned during takeoff from the St‑Mathias Water Aerodrome near Montreal. The pilot, a highly experienced seaplane operator with approximately 11 000 flight hours, was killed. The passenger, also a pilot, escaped through a window with serious injuries to his arm.
Weather and pilot qualifications were not factors. Instead, the TSB found that a maintenance error, compounded by incomplete inspections and missed opportunities during the pre-flight check, led to a reversal of the aircraft’s aileron controls. When the pilot attempted to raise the right wing during the takeoff run, “the left wing began to lift, contrary to the pilot’s expectations,” and the aircraft rolled, struck the water with its right wing and overturned.
The chain linking the control wheel to the aileron cables had been removed during winter maintenance to repair a crack in the control column. It was later reinstalled by an apprentice who did not consult the manufacturer’s maintenance manual and was not directly supervised by an aircraft maintenance engineer (AME). The chain was threaded in the opposite direction of the manufacturer’s instructions, effectively inverting the aileron response. Subsequent checks by maintenance personnel and the pilot did not detect the error.
Independent inspections under scrutiny
Critically for safety leaders, both the required AME certification and the mandatory independent inspection of the flight control system failed to identify that the ailerons were moving opposite to the pilot’s inputs. The TSB notes that the independent inspection was interrupted, and the directional movement of the ailerons “was not verified.” The report stresses that these inspections must be conducted “with no distractions or interruptions,” and that if there is any doubt or anomaly, “the entire inspection procedure be repeated” in accordance with instructions.
The investigation also highlights the pilot’s role after maintenance. For this aircraft type, the flight manual calls for a check that flight controls move freely, fully and in the correct direction before the first flight of the day. The TSB cites existing guidance that pilots should perform an “advanced” pre-flight after maintenance, be prepared to abort takeoff if anything seems abnormal, and avoid interruptions during pre-flight inspection.
Water operations, PPE and survival
Beyond control-system issues, the occurrence underscores ongoing risks associated with operations over water. Both occupants had completed underwater egress training in 2023, which likely improved the passenger’s ability to escape. However, neither was wearing a personal flotation device (PFD), and the flight, being private rather than commercial, was not subject to the regulatory requirement that seaplane occupants wear inflatable flotation devices when operated on or above water. The TSB reiterates that wearing a properly adjusted PFD from the start of the flight “considerably increases the chances of survival” if a seaplane overturns.
Following the accident, the maintenance organization added an extra independent check of directional movement of flight controls at dispatch and made specific training on Transport Canada’s control-system inspection guidance mandatory for new AMEs and apprentices.
For occupational health and safety leaders, the case offers clear lessons that reach beyond aviation: ensure strict adherence to manufacturer procedures, treat independent inspections as safety-critical work requiring protected time and focus, reinforce post-maintenance operational checks, and adopt a conservative approach to personal protective equipment, even where regulations may not explicitly require it.
