What happened
On a flight departing Les Cèdres, Quebec, the pilot of a Cessna 152, registration C-GFBJ, altered a planned training flight to a sightseeing mission over Sainte-Anne-de-Bellevue. During this unplanned route, the aircraft entered the Dorval control zone without contacting air traffic control or activating the aircraft transponder.
As an Airbus A319 operated by Air Canada was climbing out from runway 24R toward San Francisco, the crew spotted the light aircraft crossing their flight path. The pilot-flying of the Airbus executed a right turn to avoid a collision. The closest point of approach between the two aircraft was estimated to be between 100 and 200 feet horizontally as the Airbus climbed through 900 feet above sea level.
The investigation
The investigation examined the pilot's experience, the aircraft equipment, and the air traffic control environment. The pilot of the Cessna 152 had recently obtained her license and was performing her third flight. Because her previous training aircraft lacked transponders, she had developed a habit of skipping the transponder activation step on her pre-takeoff checklist. Additionally, while the pilot possessed a terminal area chart, she did not utilize it for the modified flight path.
Investigators also reviewed the performance of the Dorval tower and departure controllers. The controller's visual orientation at the time of the event made it difficult to monitor the specific area where the conflict occurred. Furthermore, the radar coordinator did not identify the Cessna as a potential conflict, and the aircraft appeared only as a primary radar target without identifying data due to the inactive transponder.
Findings
- The pilot of the Cessna 152 inadvertently entered the airspace within one mile of Dorval airport, placing the aircraft in the departure path of the Airbus A319.
- The pilot entered the Dorval control zone without obtaining ATC clearance and without activating the aircraft transponder, which prevented the Airbus's collision-avoidance system (TCAS) from providing an alert.
- A lack of flight preparation regarding the new route's landmarks and airspace boundaries contributed to the navigation error.
- Air traffic controllers failed to detect the aircraft and did not issue traffic information to the departing Airbus.
- The pilot's training history and established habits led to the failure to activate the transponder.