Air Canada Flight 624 Crashes Short of Runway in Halifax
On Sunday, March 29th, Air Canada Flight 624 crashed short of the runway during approach into Halifax Stanfield International Airport in Nova Scotia, Canada. According to the Transportation Safety Board of Canada, at about 12:40 a.m. local time, the Airbus A320 landed approximately 1,100 feet short of Runway 05, crashing into approach lights before skidding another 1,000 feet and finally exiting the runway. Out of the 138 people on board, 25 people were taken to the hospital. There were no serious injuries.
The airplane, which originated from Toronto's Lester B. Pearson International Airport, took out power lines, cutting off electricity to the airport for more than an hour, and was severely damaged. The landing gear became separated from the aircraft upon impact with an array of antennas, leaving an extensive debris field between the localizer antenna and the runway threshold. The nose cone and one of the engines also became separated from the aircraft, and the wing was severely damaged.
All passengers were able to deplane. Twenty-five people were taken to the hospital and treated for non-critical injuries.
Investigators from the Transportation Safety Board of Canada (TSB) arrived on scene and recovered the Flight Data Recorder and Cockpit Voice Recorder. The organizations said in a statement that the accident data suggested an unstable approach. "This accident displays some of the characteristics of an approach-and-landing accidents which is on TSB's Watchlist." The watchlist is a list of high-risk problems that the organization intends to address and include "…runway overruns, runway excursions, landings short of the runway, and tail strikes." The report highlights the need for pilots to pay more attention to stabilized approach criteria and execute a go-around when necessary during unstable approaches.
Statistical data from a report published by Airbus states that "continuing an unstabilized approach is a causal factor in 40 % of all approach-and-landing accidents." And according to Airbus, an approach is considered stable when all of the following conditions are met "before reaching the applicable stabilization height" (either 500 feet in VMC or 1000 feet in IMC):
- The aircraft is on the correct lateral and vertical flight path.
- Only small changes in heading and pitch are required to maintain this flight path
- The aircraft is in the desired landing configuration
- The thrust is stabilized usually above idle, to maintain the target approach speed along the desired final approach path.
- The landing checklist has been accomplished as well as any required specific briefing
- No flight parameter exceeds the criteria defined in Table 4, which lists the following parameters as being unstable:
- Vapp airspeed exceeding -5/+10
- Vertical speed in excess of 1,000 feet per minute
- Pitch attitude in excess of +/- 2 degrees pitch up or down
- Bank angle greater than 7 degrees
- Localizer deviation greater than 1/4 dot
- Glideslope deviation in excess of 1 dot
The correct procedure for an unstable approach, according to Airbus, is for the pilot to execute a go-around immediately.
"If the aircraft is not stabilized on the approach path in landing configuration, at the minimum stabilization height, a go-around must be initiated unless the crew estimates that only small corrections are necessary to rectify minor deviations from stabilized conditions due, amongst others, to external perturbations."
Officials claimed it was too early to tell if weather played a role, but the weather was reportedly "at minimums," which is pilot-speak for having the minimum required visibility and ceilings to land for an instrument approach. The aircraft apparently circled to land "for some time," but even though it was snowing, the weather was still appropriate for landing, according to a CBC report. It's unclear which instrument approach the pilots were flying at the time.
According to CBC, each of the pilots has worked at Air Canada for 15 years and each has plenty of experience in the aircraft.
The runway at Halifax airport will reportedly be out of service until the debris has been removed and the runway has been inspected. The ILS repair could take up to a month, making that particular runway unusable in instrument meteorological conditions.
The TSB will continue to investigate.