THE OCCURRENCE
On 29 March 2015, an Air Canada Airbus A320-200 aircraft (registration C-FTJP, serial number 233), was being operated as Flight AC624 from Toronto, Ontario, to Halifax, Nova Scotia, with 133 passengers and 5 crew on board.
The aircraft was flying the localizer approach procedure to land on Runway 05 at the Halifax Stanfield International Airport. A localizer approach only provides pilots with lateral guidance to align the aircraft with the runway for landing. During the approach, the engines of the aircraft severed power transmission lines, and then the main landing gear and rear fuselage impacted the snow-covered ground about 225 metres before the runway threshold. The aircraft continued through a localizer antenna, then impacted the ground in a nose down attitude, about 70 metres before the threshold. It then bounced and slid along the runway, coming to rest on the left side of the runway about 570 metres beyond the threshold.
The passengers and crew evacuated the aircraft; 25 people sustained injuries and were taken to local hospitals. The aircraft was substantially damaged. There was no post-crash fire.
INVESTIGATION TEAMWORK
The Investigator-in-charge, Doug McEwen, is assisted in this investigation by TSB investigators with backgrounds in flight operations, aircraft performance, aircraft systems, aircraft engines, human performance, and air traffic control. Representatives from Air Canada, Airbus, NAV CANADA, Transport Canada, France’s BEA (Bureau d'Enquêtes et d'Analyses pour la sécurité de l'aviation civile), the RCMP, Halifax International Airport Authority, and the Halifax Regional Police department are also providing assistance.
WORK TO DATE
A large number of technical and operational documents, weather reports, air traffic control communications, and incident reports have been gathered and are being reviewed by investigation team members. Numerous interviews have been conducted with passengers and individuals from various organizations.
The flight data recorder (FDR) and cockpit voice recorder (CVR) have been examined. With assistance from external specialists, the TSB has retrieved information from the aircraft's Digital Access Recorder, which records additional flight and aircraft parameters. Further analysis of this recorded data will be conducted.
WHAT WE KNOW
Weather
Prior to landing, the crew received an updated weather report at 12:15 am Atlantic Time which included: windspeed 20 knots gusting to 26 knots from the north north west; 350° true; with a forward visibility of ½ statute mile in snow and drifting snow. The vertical visibility was 300 feet above the ground, temperature of minus 6°C, dewpoint minus 7°C, and altimeter setting of 29.63 inches of mercury.
The aircraft
Preliminary examination of the FDR indicates the aircraft was correctly configured for landing, the airspeed was consistent with a normal approach speed, and the altimeters were set to 29.63 inches of mercury. No mechanical deficiencies were identified with the aircraft’s engines, flight controls, landing gear and navigation systems. During the review of the aircraft’s maintenance records, no discrepancies were noted. Approximately 4900 litres of fuel was recovered from the aircraft.
Post-impact damage
The forward right and both rear exits were not used during the evacuation. No discrepancies were noted during the initial examination of these exits. Examination of the aircraft revealed that the right side cabin floor in seat rows 31 and 33, and the floor adjacent to the flight attendant fold-down seat near the rear of the cabin were punctured from below by aircraft structure. No pieces of the localizer antenna structure penetrated the cockpit.
NEXT STEPS
Work will include:
- Recreating the accident flight profile as closely as possible to add to the understanding of the challenges encountered by the pilots of AC624.
- Completing a detailed site survey illustration, examining relevant aircraft components and developing an animation of the aircraft’s flight profile.
- Evaluating pilot training and experience, human performance aspects, crew resource management, industry standards and company operating procedures.
- Reviewing flight attendant training and experience as well as company procedures and regulatory requirements.
- Examining survivability issues such as cabin and cockpit crashworthiness, passenger evacuation, and airport emergency response.
- Reviewing non-precision localizer approaches utilizing a stabilized constant descent angle.
- Conducting additional interviews as required.
- Ongoing examination of aircraft structural damage.
APPROACH-AND-LANDING ACCIDENTS
The TSB Watchlist identifes approach-and-landing accidents as one issue which poses the greatest risk to Canada's transportation system. These accidents include runway overruns, runway excursions, landings short of the runway, and tail strikes. The TSB has called on operators, regulators, and air navigation service providers need to take more action to prevent approach-and-landing accidents, and to minimize the risks of adverse consequences if a runway overrun occurs.
COMMUNICATION OF SAFETY DEFICIENCIES
Should the investigation team uncover a safety deficiency that represents an immediate risk to aviation, the Board will communicate without delay so it may be addressed quickly and the aviation system made safer.
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The TSB is an independent agency that investigates marine, pipeline, railway and aviation 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:
TSB Media Relations
819 994-8053
media@tsb.gc.ca
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