A “perfect storm” of problems lies behind Air Canada’s wave of flight delays over the summer, its CEO said, even as the country’s largest airline roars back to profitability.

Despite more staff and revamped technology, Air Canada’s operations in June and July failed to meet “expected levels,” Michael Rousseau told analysts on a conference call Friday. The chief executive identified “severe weather” – thunderstorms, in particular – and “global supply chain issues” as culprits.

Flight tardiness and cancellations have particularly plagued Air Canada’s large network of regional flights, run by Jazz Aviation.

Rousseau cited a pilot shortage amid new competitors such as Flair Airlines and Lynx Air, stricter regulations on shift length as well as enrolment at flight schools, which shrank during the COVID-19 pandemic.

“We have this almost perfect storm that exists at this point in time,” Rousseau said. “We’re working hard with our partner, Jazz, on solving that problem right now, but it will take some time to transition.”

In spite of tens of thousands of delayed flights in its second quarter, Air Canada posted earnings that soared to pre-pandemic levels amid high travel demand and pricier fares.

It reported net income of $838 million for its second quarter compared with a loss of $386 million a year earlier – and nearly a billion dollars in losses through all of 2022.

Strong demand propelled more than 11 million customers across its network in the quarter, Rousseau said. Analysts also noted higher ticket prices behind the thicker profit margins.

The company ranked last among North America’s 10 biggest airlines for on-time performance in July, according to a report by aviation data firm Cirium last week.

Its planes arrived punctually 51% of the time, versus 62% for WestJet – in seventh place. Alaska Airlines, which had a similar number of monthly flights to Air Canada’s 36,000, snagged the top spot at 82.