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Air transportation safety investigation A21O0069

The TSB has completed this investigation. The report was published on 19 January 2023.

Table of contents

Mid-air collision

York Regional Police
DJI Matrice M210 (remotely piloted aircraft), C-2105569275
Canadian Flyers International Inc.
Cessna 172N, C-GKWL
Toronto/Buttonville Municipal Airport, Ontario, 1.2 NM NW

View final report

The occurrence

On 10 August 2021, the Cessna 172N aircraft (registration C-GKWL, serial number 17268441) operated by Canadian Flyers International Inc. was on a day visual flight rules training flight, on final approach to Runway 15 at Toronto/Buttonville Municipal Airport, Ontario, with a student pilot and flight instructor on board. At approximately 1301 Eastern Daylight Time, the student pilot and flight instructor heard and felt a solid impact at the front of the aircraft. Suspecting a bird strike, they continued the approach and made an uneventful landing, exiting the runway and proceeding to park on the ramp. After parking the aircraft, they observed damage on the front left cowl under the propeller; however, there were no signs that a bird had struck the aircraft.

Shortly afterward, a member of the York Regional Police reported to airport staff that he believed a collision had occurred between the remotely piloted aircraft he had been operating and another aircraft. The remotely piloted aircraft, a DJI Matrice M210 (registration C-2105569275), had been in a stationary hover at 400 feet above ground level when the 2 aircraft collided. The DJI Matrice M210 was destroyed.

There were no injuries to either pilot on the Cessna 172N or to persons on the ground.

Media materials

News release


Unsuccessful visual scanning, operator task saturation factors in 2021 aircraft/drone collision near Toronto/Buttonville Municipal Airport, Ontario
Read the news release

Investigation information

Map showing the location of the occurrence


Photo of Peter Rowntree

Mr. Rowntree has 26 years of civil aviation experience. He joined the TSB in November 1997 as an investigator/technical specialist in the TSB Air Investigations Ontario Regional Office, in Richmond Hill, Ontario

Prior to joining the TSB, he worked as an aircraft maintenance supervisor in the arctic for a major Canadian air carrier. During that time, he maintained and supervised the maintaining of different aircraft types, from small aircraft to the larger commuter and jet aircraft. Mr. Rowntree was also certified flight attendant and volunteer fire fighter.

Since joining the TSB, Mr. Rowntree has participated in numerous investigations and several major TSB investigations, most notably; the 1998 investigation into Swiss Air 111 in Peggy's Cove, Nova Scotia, the 2004 investigation into the MK Airlines accident in Halifax, Nova Scotia, the 2005 investigation into Air France accident in Toronto, Ontario, the 2009 Cougar Helicopter accident in St. John's, Newfoundland and the 2011 First Air accident in Resolute, Nunavut. On behalf of the TSB, he has also assisted numerous foreign investigation agencies in their investigations of accidents abroad.

Class of investigation

This is a class 3 investigation. These investigations analyze a small number of safety issues, and may result in recommendations. Class 3 investigations are generally completed within 450 days. For more information, see the Policy on Occurrence Classification.

TSB investigation process

There are 3 phases to a TSB investigation

  1. Field phase: a team of investigators examines the occurrence site and wreckage, interviews witnesses and collects pertinent information.
  2. Examination and analysis phase: the TSB reviews pertinent records, tests components of the wreckage in the lab, determines the sequence of events and identifies safety deficiencies. When safety deficiencies are suspected or confirmed, the TSB advises the appropriate authority without waiting until publication of the final report.
  3. Report phase: a confidential draft report is approved by the Board and sent to persons and corporations who are directly concerned by the report. They then have the opportunity to dispute or correct information they believe to be incorrect. The Board considers all representations before approving the final report, which is subsequently released to the public.

For more information, see our Investigation process page.

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.