Unsuccessful visual scanning, operator task saturation factors in 2021 aircraft/drone collision near Toronto/Buttonville Municipal Airport, Ontario
Richmond Hill, Ontario, 19 January 2023 — The Transportation Safety Board of Canada (TSB) released its investigation report (A21O0069) into the August 2021 collision between a remotely piloted aircraft, commonly referred to as a drone, and a small aircraft that took place near the Toronto/Buttonville Municipal Airport, Ontario.
On 10 August 2021, a Cessna 172N aircraft operated by Canadian Flyers International Inc. was on final approach to the Toronto/Buttonville Municipal Airport, with a student pilot and flight instructor on board, when it collided with a York Regional Police DJI Matrice M210 remotely piloted aircraft (RPA) operated by a pilot located on the ground and a visual observer. Following the collision, the Cessna aircraft continued the approach and made an uneventful landing. After parking the aircraft, damage on the front left cowl under the propeller was observed. The York Regional Police RPA was destroyed. There were no injuries to either pilot on the Cessna 172N or to persons on the ground.
The investigation found that the Cessna pilots were unaware of the presence of airborne RPA traffic in the vicinity and, due to several factors, the active scanning that is part of the see-and-avoid principle was unsuccessful in identifying the conflict. Additionally, York Regional Police policy does not require that visual observers be trained crew members, and the RPA pilot did not brief the visual observer on his role and responsibilities before the operation. As a result, the visual observer was not aware of the requirement to maintain visual line-of-sight with the RPA, nor was he trained in visual scanning techniques or aircraft identification. Finally, the RPA pilot was tasked with operating the camera system, monitoring the status of the RPA, and communicating on multiple channels. As a result, he likely became task saturated, restricting his ability to visually monitor the RPA and hear radio calls on the control zone’s mandatory frequency and the sound of incoming aircraft, both of which preceded the collision. As a result of these factors, the conflict went unrecognized and the two aircraft collided.
Following the occurrence, the York Regional Police amended its directive to include the addition of a pre-flight risk assessment tool, and an updated RPA pilot checklist. There is also additional guidance for the role of the visual observer, including a quick reference card outlining their roles and responsibilities, as well as a requirement to have a visual observer present for all operational RPA flights.
See the investigation page for more information.
The TSB is an independent agency that investigates air, marine, pipeline, and rail transportation occurrences. Its sole aim is the advancement of transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.
For more information, contact:
Transportation Safety Board of Canada