Cockpit crew representatives are urging pilots to stay disciplined and alert during ground manoeuvring at Toronto Pearson airport after a series of runway incursions at the hub.
Most incursions have taken place during operations involving the closely-spaced parallel runways 06R/24L and 06L/24R, says the International Federation of Air Line Pilots' Associations.
It says 10 specific "hotspots", where the risk of incursion is particularly high, are shown on diagrams for the airport, which features a complicated set of controlled and uncontrolled taxiways.
IFALPA says its partner association, ALPA, is strongly advising crews to review the airport information and "remain vigilant at all times", and to request clarification of instructions prior to crossing runways – particularly when the parallels are in operation.
Transportation Safety Board of Canada has opened a probe into the incursion situation at Toronto over the five years to June 2017 in order to identify underlying safety issues.
This investigation is to concentrate specifically on the south complex, which includes the closely-spaced parallels.
TSB says this complex has characteristics which are "not found" at other airports, and the probe will look at factor contributing to incursions between the two runways, which are only 1,000ft apart.