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Cessna Citation’s tailplane stalled due to icing on departure from Oslo, report
31 January 2020
Report: Runway incursion by snowplow proceeding through holding position onto active Montreal runway
The Transportation Safety Board of Canada (TSB) released its investigation report 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 2 February 2019, snow-removal operations were being conducted at the airport. A convoy of 7 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 local time when the lead vehicle in the convoy, a snowplow-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 snowplow-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.
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.
Finland concludes serious loss of separation incident at Helsinki-Vantaa Airport
The Safety Investigation Authority of Finland (SIAF) concluded their investigation into a serious loss of separation incident at Helsinki-Vantaa Airport.
On January 18, 2019, a Turkish Airlines Boeing 737-900 operating a service from Istanbul landed on runway 22L at Helsinki-Vantaa Airport, followed one-and-a half minutes later by a Norwegian Air International Boeing 737 Max 8 on a service from Krakow, Poland. Traffic situation was normal for the time of the day, and visibility was good.
Observing the Turkish airplane in the process of vacating the runway, the controller cleared the Norwegian flight to land since there was reasonable assurance that prescribed separation would exist when the flight arrived at the runway threshold. The controller also cleared two Scandinavian Airlines (SAS) flights – which were at that time on taxiway Y and link ZD – to cross active runway 22L behind the Turkish airplane and prior to the landing of the Norwegian flight.
The Turkish airplane had slowed down markedly during rollout, and by the time it entered exit taxiway ZJ it was traveling at 9 kt. Speed reduced further to approximately 4 to 5 kt on the exit taxiway, and by the time the Norwegian flight was coming overhead the threshold, the aircraft was entirely on the exit taxiway. The Norwegian pilots considered the runway clear and concentrated on landing the airplane safely. Cockpit resource management was good.
Since the controller’s focus was on the two SAS jets crossing the runway, the controller was unable to monitor continuously the movement of the Turkish airplane. It should also be noted that it is inherently difficult to discern a slow movement and assess its speed, both visually and on the surface movement radar display; this led to the belated update of the status of the Turkish airplane that was vacating the runway and of the Norwegian flight approaching from an entirely different direction. Since the controllers were unable to positively determine whether the former was stationary or in motion, they told the Norwegian flight to go around. The call consisted of a single brief message: “go around, I say again, go around.”
This instruction was transmitted at a very late stage of the landing. The pilots did not hear the message since the automated callout system was outputting voice alerts of remaining altitude (50 to 30 ft) in ten-foot increments, and the message, delivered in a normal tone and volume of speech, was masked by the loud callouts. Instead of executing a go-around, the airplane landed normally and vacated the runway along the same exit taxiway as the Turkish Airlines flight.
The investigation determined that a go-around instruction will ensure runway safety only if two conditions are met; i.e., if the controller monitors the situation actively and calls a go-around sufficiently early, and if the pilot complies with the instruction.
The investigation also disclosed that the regulations pertaining to vacating of the runway after landing are interpreted inconsistently within the Finnish controller community. An underlying safety management principle is that actions shall not contradict rules and regulations.
More information:
- Final report (pdf)
