The Department of Transportation reported this week that airline flight delays in June were worse than either May or June of last year. The airlines jumped on the news to again claim that it is an outdated air traffic control system and an "unfair" funding system that's responsible.
But if you dig deeper into the Bureau of Transportation Statistics (BTS) data, the major causes leap out: weather and scheduling. And as we've said before, tinkering with the aviation tax system and building NextGen (the air traffic modernization program) are still not going to allow airliners to penetrate a line of thunderstorms or occupy the same spot at the same time on a runway or taxiway.
"The facts clearly show that the airlines' own scheduling practices are a major cause of the problems," said AOPA President Phil Boyer. "And they can't expect ATC modernization to cure all ills."
More than 40 percent of airline delays are attributed to weather, according to the BTS. Looking at another data set, you see that the air carriers themselves are responsible for more than 25 percent of their delays through things they can control (maintenance or crew problems, baggage loading, fueling, etc.).
The issue of the airlines scheduling more flights than the airport can handle is a little more difficult to tease out of the BTS statistics. More than 28 percent of airline flight delays are attributed to "national aviation system (NAS) delays."
But that's a big pot. Included in the NAS category are delays due to non-extreme weather conditions, airport operations, heavy traffic volume, and air traffic control.
So if Airline X can't push back and taxi out when it's scheduled to because there are already too many scheduled flights trying to depart, it will be classified as an NAS delay. And it's the airlines themselves that determine how they are going to classify and report a delayed flight.
But AOPA analyzed the June airline schedules at all of the major airports. And at 17 out of 35 hub airports, the airlines have scheduled more flights during their daily "pushes" than the airports can handle in instrument weather conditions. It doesn't take a thunderstorm to delay flights all across the country. Just have visibility drop below three miles or the ceiling below 1,000 feet at one of these 17 major airports and flights will be delayed.
Some of the worst airports for overscheduled airline flights include Chicago O'Hare, Atlanta Hartsfield, Newark, John F. Kennedy, Minneapolis-St. Paul, Salt Lake City, San Francisco, and Las Vegas McCarran.
Weather and scheduling. That's what causes airline delays.
The airlines think they should be able to cut in front of all other air traffic, according to the Air Transport Association. In an opinion piece on USA Today's August 8 editorial page, ATA President James May says one solution to airline delay problems is to "give commercial flights a higher priority than other system users to protect schedule integrity."
But it's not the other aircraft in the system that are delaying airliners. Even the USA Today editorial writers said, "The situation is aggravated by the airlines' practice of scheduling more 'rush hour' flights than some airports can accommodate, even under perfect conditions. On Tuesday, 57 flights were scheduled to take off from New York's Kennedy Airport from 8 a.m. to 9 a.m. — about a dozen more than top airport capacity, according to air traffic controllers." The Department of Transportation says scheduling and weather are the biggest causes of airline delays.
And airline flights already get priority in the air traffic control system. Mr. May, who is not a pilot, may not know this, but any pilot with experience flying IFR certainly does.
It's not an official FAA policy, but practical reality is that air traffic controllers work to keep the flow of airliners steady. If you're too low or slow to go with the flow, you will be vectored to the "back 40" until a big enough hole opens up for you to get in without disrupting airline arrivals and departures.
Even pilots of corporate jets that can fly higher and faster than airliners sometimes find themselves taking the long way around or holding in favor of the airlines' schedule.
Consider this recent case. A pilot of a piston-engine aircraft was well south of New York City when he asked air traffic control to approve a course change to avoid a thunderstorm. "Too busy with inbounds to JFK," was the response. ATC was clearly giving priority attention to his airline traffic.
Or consider this report from a California pilot returning from a trip to Reno, Nevada. "I was making an approach into Van Nuys Airport. There was a Southwest 737 approaching for landing at Burbank. The controller asked me to make a 360 so 'he could get the Boeing in.' I happily complied. The jet flew behind me and landed without one second of delay. GA causing airline delays?"
Updated: August 10, 2007, 3:43 p.m. EDT