Air Canada ERJ-190 Lands Despite Two Go-Around Instructions at Toronto Airport

Toronto, Canada – On March 11th, 2013, an Air Canada Embraer ERJ-190, registration C-FLWH, narrowly avoided a serious incident during its final approach to Toronto Pearson International Airport. The aircraft, performing flight AC-178 from Edmonton, was cleared to land on runway 24R when air traffic control issued two urgent instructions to go around, both of which were not acknowledged by the flight crew. The aircraft continued its approach and landed safely, but the incident has raised significant concerns about communication and safety protocols.

Incident Overview

As flight AC-178 approached runway 24R, the tower controller at Toronto’s Pearson Airport noticed an unexpected ground radar target moving across the runway. This target was later identified as a maintenance vehicle that had inadvertently rolled away from its parking position near a Sunwing Boeing 737-800 at Gate H16. The vehicle, which had been left unattended with its engine running and transmission in drive, crossed the active runway just as AC-178 was on final approach, approximately 0.75 nautical miles from the threshold.

Recognizing the potential danger, the tower controller instructed the flight to go around, issuing the command twice: “178, go around” and then repeating “178, go around.” Both instructions went unanswered by the flight crew, who later reported that they had heard the calls but mistakenly believed they were directed at another aircraft. The Embraer passed directly over the vehicle, missing it by approximately 35 feet, before landing safely on the runway.

Post-Incident Findings and Investigation

In the immediate aftermath, the crew was queried by air traffic control about their failure to respond to the go-around instructions. The crew explained that they had heard the command but did not see any obstacles on the runway, leading them to believe the instructions were not intended for their flight. This miscommunication highlighted the dangers of ambiguous or unclear instructions during critical phases of flight.

A subsequent investigation by Canada’s Transportation Safety Board (TSB) revealed several contributing factors to the incident. Key among these was the malfunction of the airport’s surface detection equipment (ASDE) and runway monitoring and incursion alert system (RIMCAS). The ASDE was not actively monitored at the time of the incident, and the Stage 1 RIMCAS visual alert went unnoticed by the controllers. Additionally, the Stage 2 aural alert was triggered only two seconds before the conflict, far too late to be of any practical use.

The TSB also identified that the vehicle’s beacon did not meet the standards required for airport operations, making it less likely to be seen by ground personnel, the flight crew, or air traffic control. Furthermore, the investigation found that the first go-around instruction from the tower was masked by a louder callout from the aircraft’s enhanced ground proximity warning system (EGPWS), preventing the crew from hearing it. The second instruction was compromised by rapid speech and audio truncation, leading to the omission of the aircraft’s call sign from the transmission.

Analysis and Safety Recommendations

The TSB’s analysis focused on the sequence of events that allowed the vehicle to cross an active runway unnoticed and the communication breakdown that nearly led to a collision. The investigation found that all personnel involved were properly trained and experienced, ruling out fatigue or lack of competency as factors. Instead, the report emphasized the importance of clear and unambiguous communication, especially during critical operations like landing.

The report also noted the failure to secure the maintenance vehicle, which was left in drive gear, as a primary cause of the incident. This oversight allowed the vehicle to slowly roll across the runway, undetected by both ground personnel and air traffic controllers until it was nearly too late.

The TSB recommended improvements to airport surface detection systems, including the adoption of newer ASDE technologies capable of identifying ground vehicles and aircraft more effectively. Additionally, the report called for enhanced procedures to ensure that vehicles are properly secured when left unattended, as well as better training for air traffic controllers in monitoring and responding to ground radar alerts.

Conclusion

The March 11th incident involving Air Canada flight AC-178 serves as a stark reminder of the complexities and dangers inherent in modern aviation, where even small lapses in communication or procedural adherence can have potentially catastrophic consequences. While the quick actions of the flight crew in maintaining a stable approach and landing were commendable, the incident underscores the need for continuous vigilance and improvement in both technology and human factors within the aviation industry.

As a result of this event, both Air Canada and Toronto Pearson Airport have likely reviewed and updated their safety protocols to prevent a recurrence, ensuring that such a near-miss does not escalate into a tragedy in the future. The lessons learned from this incident will contribute to the ongoing efforts to enhance aviation safety worldwide.