The Financial Post reports in its Monday edition that a new report says Air Canada ranked last in on-time performance among the 10 largest airlines in North America. A Canadian Press dispatch to the Post says that Canada's biggest carrier landed 51 per cent of its flights on time last month, according to figures from aviation data firm Cirium. WestJet Airlines, which placed seventh, saw 62 per cent of its trips make it to the gate on time -- defined as within 15 minutes of scheduled arrival. The two top performers were Alaska Airlines and Delta Air Lines, which notched 82 per cent and 79 per cent, respectively. North American airlines' average on-time performance was 66 per cent, the worst by far of any of the regions tracked in the report, including Europe, Latin America and the Middle East and Africa. On top of a shortage of air traffic controllers, Air Canada has pointed to thunderstorms and a network running at full tilt amid high demand, which can mean longer recovery times after a disruption. Around 140,000 passengers per day flew on Air Canada's 36,000 trips last month, the airline said in a statement to CP. Late arrivals mean a smaller window to carry out preventive maintenance between flights overnight.