Air transportation safety investigation A24W0008

Collision with terrain

Northwestern Air Lease Ltd.
BAE Systems Jetstream 3212, C-FNAA
Fort Smith Airport (CYSM), Northwest Territories, 0.7 NM NW
23 January 2024

The occurrence

At 0642 Mountain Standard Time (MST) on 23 January 2024, the BAE Systems Jetstream 3212 aircraft (registration C-FNAA) operated by Northwestern Air Lease Ltd. was destroyed when it collided with terrain shortly after takeoff from Runway 30 on a scheduled flight from Fort Smith Airport (CYSM), Northwest Territories, to the Diavik Diamond Mine Aerodrome (CDK2), Northwest Territories. Six people were fatally injured, 1 person received minor injuries.

Work completed at 23 February 2024

Multiple interviews have been conducted in support of the investigation. The cockpit voice recorder (CVR) has been recovered, and the data for the flight, which was good quality, has been downloaded. Closed-circuit television (CCTV) footage of the fuelling, passenger loading, and departure has been collected for further analysis. The aircraft wreckage has been transported to the TSB’s regional office in Edmonton, Alberta, for further examination. The engines have been removed from the wreckage and will be shipped to the manufacturer for detailed examination.

What we know

At 0600 MST, the limited weather information system (LWIS) reported winds from 300° true (T) at 2 knots, a temperature of −19 °C, and a dew point of −22 °C. At 0700 MST, the LWIS reported winds from 290°T at 3 knots, a temperature of −19 °C, and a dew point of −22 °C. At 0701 MST, a special weather observation was made, which reported winds from 290°T at 3 knots, visibility of 2 statute miles in light snow, an overcast ceiling at 7300 feet above ground level (AGL), a temperature of −19 °C, and a dew point of −22 °C. CCTV footage showed that it was actively snowing during the fuelling, passenger loading, and taxi processes.

The aircraft was cold soaked in the hangar before being pulled out and fuelled for the intended flight. The fuel used for the flight had been stored in an above-ground storage system and both ground personnel and a flight crew member inspected the wing surfaces to check for the adherence of snow. After the passengers had boarded and the baggage was loaded into the aircraft, the flight crew started the aircraft and proceeded to taxi for departure from Runway 30. Both flight crew members held the appropriate licences and ratings for the flight in accordance with existing regulations. The aircraft had a maximum approved take-off weight of 16 204 pounds. Its weight at departure was approximately 15 050 pounds.

Automatic dependent surveillance – broadcast (ADS-B) data was obtained and indicated that the aircraft attained a maximum height of 140 feet AGL, and a maximum groundspeed of 160 knots. After reaching 140 feet AGL, the aircraft entered a descent and impacted the tops of trees at the end of the runway clearing approximately 3075 feet from the end of Runway 30. The aircraft continued to descend as the terrain elevation also decreased, before impacting terrain 4150 feet from the end of Runway 30 and 620 feet left of the extended runway centreline.

There was an extensive post-impact fire, which consumed the majority of the centre section of the aircraft. During the accident sequence, 1 passenger was ejected from the aircraft and received minor injuries. This person was rescued at approximately 1030 MST.

The aircraft’s emergency locator transmitter activated and the Joint Rescue Coordination Centre received a signal. All major components of the aircraft were accounted for at the accident site.

Next steps

The TSB will continue to liaise with the aircraft and engine manufacturers, the operator, and Transport Canada. Should critical safety issues be identified during the investigation, the TSB will immediately notify relevant parties so appropriate and timely safety action can be taken.

This accident investigation is ongoing and currently in the initial analysis phase. A final report will be released at the conclusion of the investigation.

Media materials

Deployment notice

Investigation information

Map showing the location of the occurrence

Investigator-in-charge

Jeremy Warkentin joined the Transportation Safety Board of Canada (TSB) in 2017 as a Regional Senior Technical Investigator, in the Aviation Investigations Branch, at the regional office in Edmonton, Alberta.

Mr. Warkentin is a graduate of the British Columbia Institute of Technology’s Aircraft Maintenance Engineer (AME) program and has more than 20 years of aviation experience working for several fixed wing operations as a licensed Aircraft Maintenance Engineer, Quality Assurance Manager and Base/Production Manager. He holds both an M1 and M2 license, and has experience on aircraft ranging in size from the Cessna 152 to the Airbus A321.

Photos

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.