More than half of Air Canada's flights during Canada Day weekend were cancelled, delayed

Air Canada delayed or cancelled nearly 2,000 flights over the Canada Day long weekend, potentially foreshadowing more trouble ahead for passengers.

Roughly half of all trips by the country's biggest airline — including its lower-cost Air Canada Rouge and regional partner Jazz Aviation — were disrupted Saturday through Monday, according to figures from tracking service FlightAware.

The 1,965 flight delays and cancellations — affecting more than 52 per cent of scheduled flights — stand in contrast to numbers from other Canadian carriers including WestJet, Air Transat and Flair Airlines, which registered lower flight disruption levels.

The numbers also mark an uptick from the previous weekend, despite an unexpected shortage of air traffic controllers at Nav Canada that snarled travel during that period.

Posts and photos of snaking lines and bulging terminals at airports in Toronto and Montreal popped up on social media over the past few days, as passengers vented their frustrations about late takeoffs and customer service in a throwback to scenes of post-pandemic airport chaos a year ago.

Air Canada pointed out that the air travel sector is now in the throes of its summer peak, with 140,000-plus customers boarding the airline's planes daily.

"Our top priority is to ensure everyone travels safely, even if it requires extra time," spokesperson Peter Fitzpatrick said in an email.

Nonetheless, disruption figures have been trending upward over the past few weeks, said John Gradek, who teaches at McGill University's aviation management program. Crowded flight schedules and crew shortages play a role in peak season, he said, since it's harder to find a spare plane or pilot to help fill a gap when each aircraft is flying more.

"There's a lot of people flying, planes are full, and there's very little operational reliability or operational backup," Gradek said.

"If an airplane craps out, for whatever reason — mechanical things do happen — you've got to fix the airplane before you go. So you automatically take these monstrous delays or you cancel."

Air Canada is juggling a more "tightly wound" schedule after the industry-wide revenue collapse prompted by COVID-19 travel restrictions, Gradek added, with the company operating at roughly 90 per cent of its pre-pandemic flight capacity.

The carrier echoed that message, pointing out that it may take longer to recover from a wrench in the gears when any system runs at full tilt.

"For example, when thunderstorms halt our operation, as we saw over the recent weekend in the U.S. northeast, we may require more time than scheduled to get aircraft into position for their next flights," Fitzpatrick said.

He added that Air Canada is fully staffed, with more employees than in the summer of 2019, despite running fewer flights.