What U.S. Airline Passengers Complain About Most When They Fly

Yesterday Brent Bowen and Dean Headley released their 25th annual Airline Quality Rating report, and it wasn't good news for U.S. domestic airlines.

According to their report, it was the worst year to fly since 2009, with declines in each of the four performance areas that it tracks. Virgin America was at the top of the ratings for the third year in a row, while American Airlines's regional carrier American Eagle brought up the rear, along with other regional carriers in close dubious pursuit. Delta Air Lines, ranked third, scored highest amongst the major carriers, with rivals American and United Airlines in seventh and ninth, respectively.

The report itself begins with a collection of stats and data from the U.S. Department of Transportation that the authors then analyze and weight depending based on a formula created with the input of 65 airline industry experts. From on-time departures to lost baggage to time on the tarmac, the report captures the minutia of modern flying.

But outside of the stats the airlines are required to supply the DOT, there are the numbers that come from flyers themselves in the form of what they are most upset about when they fly -- upset enough to file a complaint. Complaints in 2014 were up 21% over the previous year as 1.38 out of every 100,000 flyers was angry enough to write down what displeased them.

The overwhelming complaint was related to general flight problems, followed by baggage issues and boarding and reservation complaints.

The least frequent complaint? Pets.

The full list is below.

Complaints Received by Department of Transportation for All U.S. Domestic Airlines by Complaint Category

Source: Air Travel Consumer Report, U.S. Department of Transportation, Office of Aviation Enforcement and Proceedings