Through August, the on-time average this year among the 10
mainline airlines tracked by the Department of Transportation (DOT) was 77.4%.
But for all but the most informed observers, that figure is misleading.
The reason is a simple matter of semantics. In plain
English, of course, on time means arriving at the scheduled time. But that's
not what it means in airline industry parlance.
Instead, the DOT, since it began requiring airlines to
submit on-time data in 1987, has defined an on-time flight as one that arrives
within 14 minutes and 59 seconds of its scheduled arrival.
It's a standard known as A14, with "A" standing for arrival
and "14" denoting minutes. According to a recent analysis by OAG, it's a metric
that has largely been adopted by industry regulators around the world. However,
debate remains about the value of using what is widely seen as a rather quirky
For example, Judson Rollins, founder of New Zealand-based
consultancy Propel Aviation Solutions, argues that the DOT should be focusing
instead on A0, a measurement that is based on arriving at or before the
scheduled time "because that’s what the customer cares about."
OAG, conversely, raised the question of whether a more
lenient definition of "on time" would be appropriate.
"Fifteen minutes, 20 minutes, 30 minutes. Many of us have
been delayed that long, and it wasn't so bad," the OAG analysis states. "We
could tell ourselves that maybe 30 minutes makes more sense and is certainly
more realistic in an operating environment where so many factors which
contribute to delays lie outside the control of an airline."
Exactly how the A14 standard was developed is a bit of a
mystery. The DOT didn't directly answer a question about it for this report,
and IATA spokesman Perry Flint said the organization had no subject expert on
the matter. The trade group Airlines for America said that it believes the
standard dates to the 1950s, but it didn't offer an explanation of its original
rationale. OAG senior analyst John Grant said he believes the idea of A14
emanated from IATA.
"It was an arbitrary time standard that was set in the
annals of time," he said. "There is simply no more to it than that."
Defining flights that reach the gate 14 minutes and 59
seconds late as on time clearly has the effect of making airlines appear
timelier than they are. But Grant said the standard has tangible benefits for
both airlines and passengers.
If airlines lacked that 15-minute cushion, they would likely
need to increase aircraft turn times and take on additional planes in order to
keep up on-time performance, he said. Those steps would add costs that airlines
would likely pass on to passengers. Further, the use of additional aircraft
would be a net negative from an emissions standpoint, Grant said.
Rollins, though, said that airlines should hold themselves
to an A0 standard, both for the sake of their customers and for operational
reasons. He argued that the more an airline is willing to tolerate being behind
its scheduled time, the more complications connecting passengers can expect.
"So you have to build more padding into the system," Rollins
said. "You have longer turn times, longer block times. You are essentially at a
Rollins said that airlines should actually focus most
closely on departing on time, since arrival times are sometimes out of their
control due to airport and air traffic control delays. Meanwhile, on-time
departures correlate to on-time arrivals.
Some airlines agree.
For example, at the ARC Travel Connect conference in
October, United president Scott Kirby said that on-time departure (known as D0)
is more important than an airline’s DOT on-time percentage. United’s A14
performance this year, incidentally, was seventh among U.S. mainline airlines
Meanwhile, in early 2017, Delta, which is consistently among
the industry leaders in on-time performance, updated its corporate "operational
performance commitment" (OPC) to replace A14 with A0. In the OPC, Delta
guarantees it will be timelier than American or United each year.
Bob Somers, Delta's senior vice president of global sales,
said at the time, "The addition of A0 to the OPC ensures that our standard of
on time meets that of our customers."
The A14 standard is supported by Airlines for America,
however. Early this year the trade group told the DOT that any effort to change
the on-time definition should be undertaken, "if at all," through a formal rulemaking,
spokeswoman Katherine Estep wrote in an email. She said that changing the
standard could cause concerns such as increased fuel consumption and greater
difficulty in comparing operational results over time.