On flights from Atlanta to Chicago O"™Hare during the first half of this year, American, United, Frontier and Spirit each had average gate-to-gate times of between 127 and 129 minutes. Yet on-time stats for the four airlines were markedly different.
That variance points to a flaw in the Department of Transportation (DOT) system for calculating on-time arrivals: Airlines are allowed to set their own average gate-to-gate expectations "” known as "block time" in industry parlance "” and each carrier manipulates that expectation to accommodate its own corporate priorities, which can range from brand image to labor cost containment.
American, with an average block time of 129 minutes, reached O"™Hare within 15 minutes of its schedule 78% of the time. In contrast, Spirit, which also averaged 129 minutes on the Atlanta-O"™Hare route, arrived within 15 minutes of schedule just 40% of the time.
Similarly, Frontier completed the route in an average of 128 minutes but arrived within 15 minutes of schedule "” the metric the DOT uses to define on-time arrivals "” just 49% of the time. United, on the other hand, flew from Atlanta to O"™Hare in an average of 127 minutes, good enough for an on-time arrival rate of 71%.
As a result of these apples-and-oranges block times, passengers who attempt to compare on-time performance of various carriers when making a booking decision can in fact be basing their choice of a carrier on flawed assumptions about the DOT"™s data.
On-time arrival statistics, along with cancellation numbers, are the most often cited performance indicators for airlines. Indeed, those figures are so important to airline customers that this summer Delta rolled out a pledge to its corporate clients: We"™ll give you flight credits, the Atlanta-based carrier said, should we trail American and United over a calendar year in both measures.
But as the Atlanta to O"™Hare figures suggest, operational times are just one piece of the complicated scheduling puzzle that ultimately determines an airline"™s on-time performance. And low-cost carriers, faced with the most pressure to keep prices down, are especially challenged when it comes to scheduling…
