2021 forced landing of an aircraft due to fuel starvation highlights the importance of proper checklist usage
Edmonton, Alberta, 24 November 2022 — Today, the Transportation Safety Board of Canada (TSB) released its investigation report (A21W0098) into the 2021 forced landing of an Air Tindi Ltd. de Havilland DHC-6-300 Twin Otter aircraft near Fort Providence, Northwest Territories (NWT), following fuel starvation. The investigation found that leading up to the event, there were several instances where checklists were not completed in accordance with company procedures.
On 01 November 2021, an Air Tindi Ltd. de Havilland DHC-6-300 Twin Otter aircraft departed Yellowknife Airport, NWT, on a visual flight rules flight to Fort Simpson Airport, NWT, with two flight crew and three passengers on board. Approximately 40 minutes into the flight, the crew realized that there was insufficient fuel to continue to Fort Simpson or to return to Yellowknife. The flight crew diverted the aircraft to Fort Providence Aerodrome and shut down the left engine to conserve fuel. Shortly after, the right engine flamed out. A forced landing onto muskeg was performed 6.7 nautical miles (14 km) northwest of Fort Providence Aerodrome. Approximately four hours after the forced landing, all occupants were recovered by rescue personnel. All occupants received minor injuries related to hypothermia. The aircraft sustained substantial damage.
The investigation determined that the aircraft had not been refuelled prior to departure. While conducting the Before Start checks from memory, the captain interrupted his routine by conversing with a passenger. Consequently, the fuel quantity check was missed and the preparation for flight continued without the captain being aware that the aircraft did not have sufficient fuel for the flight on board. While taxiing to the runway, the captain conducted the Taxi checks alone, silently, and from memory. Consequently, the fuel check on the checklist was missed and the aircraft departed with insufficient fuel for the flight. The first officer then completed the cruise checks silently and without reference to a checklist. As a result, the fuel state of the aircraft was not identified by either flight crew member.
A few of the experienced Air Tindi Ltd. DHC-6 captains within the company had developed the practice of performing some of the challenge and response checklists by memory only. This had become routine for most of their flights. Reporting is extremely important to a properly functioning safety management system (SMS). The investigation revealed that DHC-6 first officers who experienced deviations from company procedures tended to report informally rather than use the company SMS. As a result, company management, as a whole, was not fully aware of the deviation regarding checklist usage on the DHC-6 fleet, and did not have an opportunity to evaluate the risk and pursue a corrective action plan through the SMS. Safety management is an issue on TSB Watchlist 2022.
Following the occurrence, Air Tindi Ltd. enhanced checklist requirements and issued a company memo to flight crews emphasizing the requirement to follow all procedures and checklists. The company also enhanced fuelling procedures by requiring the captain to verify aircraft fuelling and sign an acknowledgement on every fuel slip before starting the engine. Flight crews are also required to communicate the fuel levels on board to the operations control centre before each departure.
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