Runway incursion by snow plow proceeding through holding position onto active runway

The Transportation Safety Board of Canada (TSB) released its investigation report (A19Q0015) January 21, 2020 on an incident in which four snow-removal vehicles entered an active runway at Montréal/ Pierre Elliott Trudeau International Airport as an aircraft was preparing to land.

On February 2, 2019, snow-removal operations were being conducted at the airport. A convoy of seven vehicles was instructed to proceed from Runway 24R to holding bay 24L. At the same time, a Bombardier CRJ 200 operated by SkyWest Airlines was flying the instrument landing system approach and had been cleared to land on Runway 24L. A runway incursion occurred at 11:19:04 EST, when the lead vehicle in the convoy, a snow plow-sweeper, crossed the runway holding position and

continued onto the runway. The flight crew initiated a go-around, flying over the lead vehicle in the convoy, which had been followed by three additional snow plow-sweepers. The aircraft landed safely about 15 minutes later. The convoy subsequently regrouped and completed the snow-removal operations. There were no injuries or damage.

The TSB has identified a series of causes and contributing factors in this runway incursion. The investigation found that the convoy lead, focused on the tasks of driving, snow removal, and planning the next snow-removal pass, missed the runway holding position lighting, signage, and markings, forgot about the requirement to hold short, and proceeded onto Runway 24L. Three other vehicles in the convoy followed the lead vehicle and passed the runway holding position, which increased the severity of the incursion. The ground controller on duty was multitasking and conducting an operational phone call, which led to a breakdown of his scanning and monitoring, delayed his response, and increased the incursion’s severity.

“This was a slow day for Montreal in respect to aircraft movements, but the ground personnel were still busy because of snow fall,” says JeanPierre Régnier, senior investigator for the Transportation Safety Board of Canada. “As you can imagine, in degraded weather conditions, they were busy and they had a lot of work to do. The convoy lead, although he was experienced and qualified for the job, he was concentrated on his next activity, which was snow removal on the next runway and he just drove by holding position.”

“I think that Aéroports de Montréal has done a considerable amount of work since the occurrence to debrief ground crews and personnel, and modify the procedures to hopefully prevent similar events from happening in the future,” says Jean-Pierre Régnier, senior investigator for the Transportation Safety Board of Canada.

The investigation also found that if vehicle operator training does not include runway incursion scenarios, convoy operators may not be sufficiently prepared to take necessary safety actions to reduce the associated risks. Further, air traffic control instructions that direct ground vehicles to runways and do not contain explicit instruction to hold short of an active runway can increase the potential for misunderstanding and increase the risk of an incursion.

Following the occurrence, Aéroports de Montréal (ADM) held meetings to raise awareness of runway incursions and to obtain employee feedback on the occurrence. An internal investigation within the ADM safety management system was conducted, including brainstorming/mapping and a risk analysis of the event. ADM modified procedures and employee training, and has added the issue of runway incursions to the agenda for its next meeting with NAV Canada’s Runway Safety Action Team.

“I think that Aéroports de Montréal has done a considerable amount of work since the occurrence to debrief ground crews and personnel, and modify the procedures to hopefully prevent similar events from happening in the future,” says Régnier. “They have done a great job in supporting the TSB investigation of this occurrence.” ■