The causes of flight delays

When traveling, there are places at which I have slept on multiple occasions. For example, I have slept at the Hilton in Costa Mesa many times (I even blogged about my time in the hotel at least once), and I slept at the Westin Ottawa a few times during the early 2000s.

But there's another place where I've slept more than once.

Dallas Fort Worth International Airport.

The first time was in June, when my family and I were flying from Dulles Airport to Ontario Airport, with a connecting stop in Dallas. Unfortunately for us, a major thunderstorm hit the Washington area while we were on the airplane waiting to take off. After a couple of hours on the plane, we returned to the terminal, and we ended up leaving several hours later than scheduled, missing our connecting flight to California. We arrived at Dallas around midnight, right around the time that the airport was distributing cots to other stranded passengers. After a few hours of restless sleep, we then boarded a flight for Ontario the following morning.

Come September, I was finishing up a business trip in Tampa, Florida, and waiting for my plane to arrive to take me to Dallas. Right before we were supposed to board, those of us with cell phones began receiving notifications of a multi-hour flight delay. Weather was not the culprit this time; a cracked windshield was. (You REALLY don't want to be up in the air with a cracked windshield.) So again I arrived late in Dallas, but by the time I got to my terminal for my connecting flight, the cots had all been distributed. (A helpful airport employee rounded up three blankets for me.)

So last week, when I happened to see a report from the U.S. Department of Transportation regarding flight delays, I was definitely interested. The report only covered August, and not the months of MY delayed flights (June and September), but it was still interesting to see the causes of the delays.

In August, the carriers filing on-time performance data reported that 22.43 percent of their flights were delayed – 6.35 percent of their flights were delayed by aviation system delays, compared to 6.39 percent in July; 7.65 percent by late-arriving aircraft, compared to 8.64 percent in July; 6.04 percent by factors within the airline’s control, such as maintenance or crew problems, compared to 6.68 percent in July; 0.67 percent by extreme weather, compared to 0.86 percent in July; and 0.04 percent for security reasons, equal to 0.04 percent in July. In addition, 1.38 percent of flights were canceled and 0.30 percent were diverted.

So my June delay would be classified as "extreme weather." Not sure how the September delay would be classified - while the cracked windshield was a "maintenance" problem, was that truly within the airline's control?

But the biggest cause of airline delays in August was due to late-arriving aircraft. Unfortunately, the report doesn't dig into the question of WHY the aircraft were late - for example, was it due to extreme weather at the takeoff airport?