Snyder: Padded flight times a reasonable buffer

By Brett Snyder, Special to CNNPublished 27th September 2011
planes taxiing
Do airlines pad flight times just to inflate their on-time rankings?
That's a question that has been asked by many over the years, and yes, it can happen. You've probably heard it before: A flight from Los Angeles to New York is scheduled to take longer today than it did 30 years ago.
But the reason for increasing the scheduled flight time is rarely as nefarious as many might think. Most of the time, it's done because it actually takes longer to fly the route thanks to weather, air traffic control delays and airport congestion. If that's the case, why did you arrive so early on your last flight? It's because there is a ton of variability.
Let's start with air traffic congestion. There are a lot more airplanes flying today than 30 years ago, and the situation is at its worst in New York, where delays are quite common. In these congested airports, the federal government determines how many flights can be operated and the airlines work within those parameters.
Beyond basic congestion, there is weather-related congestion. In San Francisco, when the fog rolls in, the allowable number of flight arrivals gets cut in half. Thunderstorms can wreak havoc on operations at almost any airport, and winds can have an impact as well.
All this comes together to form a very uncertain picture. If an airline could guarantee that a flight would take the same amount of time each day, then scheduling would be easy. But it's not, so airlines have to make judgment calls.
Let's look at American Airlines Flight 1, which operates from New York JFK to Los Angeles at 9 a.m. The flight is scheduled to take 6 hours and 10 minutes from gate to gate, but it can vary greatly.
On September 4, the airplane spent 6 hours in the air alone, forget about taxi time. Less than a week later on September 10, that flight took only 4 hours and 51 minutes. The result? Both flights left the gate about 20 minutes late, but the first one arrived 42 minutes late while the second arrived 51 minutes early.
As you can see, flight times are highly variable, and though these are extremes, smaller variations happen all the time. With that in mind, airlines go into their scheduling decisions knowing they won't get it right. They just have to do the best they can with the data they have.
Now that's not to say that different airlines don't have different ways of setting their scheduled times. Delta's 9 a.m. flight is scheduled for 2 minutes less than American's and JetBlue's 9 a.m. flight is 3 minutes less than that. Why the difference?
Well, they operate different airplanes and each aircraft type has a different optimum cruising speed. In addition, they sit in different terminals at both airports, and the taxi times can take longer for one than another. Sometimes, however, there are other factors at work.
In 2000, I worked at America West Airlines and we were running an operation with a lot of delays and cancellations. A new chief operating officer was brought in to right the ship, and in the beginning, that meant putting more scheduled time on each flight. This buffer helped give the airplanes a little more down time while other issues were fixed.
Eventually, the operation improved and the scheduled flight times went back to normal. This, of course, goes back to the original question.
Do airlines pad the flight times so the flights arrive on time more often? The Department of Transportation judges a flight as being on time if it arrives within 15 minutes of schedule, a buffer that makes it easy to run an on-time operation. That's actually not a bad thing for travelers.
Charlie Leocha, director of the Consumer Travel Alliance advocacy group, says his organization is not against padding flight times "because at least the new times are more realistic. We understand that tighter airspace and the possibilities of delays are increasing, especially in the Northeast. At least consumers will have a more realistic time frame within which to operate."
For most airlines, however, long-term padding just to have a buffer is a terrible idea. The more time that gets built into the schedule, the fewer flights that airplane can fly in a day. An airplane on the ground isn't making any money, so airlines have the incentive to get that aircraft in the air as often as possible. Building in extra ground time goes against that goal and leads to higher costs.
Because of that, padding flight times is most often used as a temporary solution when an operation is having problems and not as an on-time performance marketing tool. It's better to add more buffer so customers arrive on time instead of consistently having them arrive late. But in the long run, the airlines have no real incentive to keep doing that.