The CrowdStrike and Microsoft IT outage that started July 19 threw the aviation industry into “disarray” and was a cause in the “notable decreases” in July on-time performance scores for the regions most affected by the outage, particularly North America, Europe and Asia-Pacific, according to aviation analytics company Cirium.
In North America, nine of the 10 carriers in Cirium’s monthly report posted on-time performance declines. Only Frontier Airlines’ performance gained from June, up 1.1 percentage points to 65.3 percent. WestJet had the largest drop, down 11.1 percentage points to 60.9 percent.
Delta Air Lines was the most affected carrier by the outage in North America, and for the first time since July 2023 it was not the leader in the region’s on-time performance. Instead, Alaska Airlines was the top carrier, with an on-time performance of 77.5 percent, just shy of its June average of 77.8 percent. United Airlines followed at 73.1 percent.
Still, Delta—despite thousands of canceled and delayed flights and taking longer than other carriers to get back on schedule—still managed to come in third, at 72.4 percent, down 7.7 percentage points from June.
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None of the North American carriers made the global list of top performing airlines for July.
The outage effect also showed up in the number of canceled flights for July. North American carriers for the month canceled nearly 23,400 flights, nearly double the 11,800 canceled in June.
Southwest Airlines had the highest completion factor for July at 99.43 percent, followed by Alaska at 99.40 percent. JetBlue was third at 98.73 percent.
A flight is considered on time if the aircraft arrives at the gate within 15 minutes of its scheduled arrival time.
