Delta Air Lines retained its first-place ranking in September North American airline on-time performance as the average for the category jumped 7.1 percentage points from August, according to aviation analytics company Cirium's latest monthly report.
Delta led with an 87.5 percent on-time average. Alaska Airlines was second at 84.6 percent, followed closely by WestJet, which soared 14.1 percentage points to an average of 84.5 percent. Each of the carriers included in the September report posted month-over-month improvements in the metric.
Overall September North American airline on-time performance was 82.9 percent.
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Three North American airlines made Cirium's global list of top on-time carriers: Delta, WestJet and United Airlines (84.2 percent). Aeromexico took the global top spot with an on-time performance of 91.8 percent.
The top five North American carriers for completion factor each were above 99 percent, led by Delta at 99.7 percent, Spirit Airlines at 99.7 percent and United at 99.6 percent.
The number of flights canceled in September was 5,364 compared with 12,223 in August.
A flight is considered on time if the aircraft arrives at the gate within 15 minutes of its scheduled arrival time.
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