Airline-related complaints made to the U.S. Department of Transportation (DOT) from 2002 to 2012  reveal that passengers were less likely to make a formal complaint about service quality if they were on a long-established "network" carrier.

Passengers of low-cost upstarts tended to complain less, even though the quality of service may have been just as poor.


The difference was not small. The paper in the Journal of Air Transport Management found that, regardless of the type of service failure, passengers complained up to 10 times more often about network carriers than low-cost carriers.

Michael Wittman, a graduate student in MIT's International Center for Air Transportation, speculates on ways to explain the discrepancy: he believes that passengers of low-cost carriers may not be aware of the option to complain to the federal government, that expectations of service quality may be lower or that front-line customer service — how airline agents address mishaps — may be better at low-cost carriers.


That last part may make sense. Each customer is dramatically more important to a small airline while every American air traveler knows that large carriers are all union employees, and the perception among much of the public is that a union job means the quality of service is unimportant. In that instance, passengers the federal government is the only recourse.

Wittman obtained data from the Air Travel Consumer Report, a monthly report by the Department of Transportation (DOT) Airline Consumer Protection Division, which publishes service-quality data that airlines are required to submit to the DOT. Such data include the number of flight delays and cancellations, bags misplaced or lost, and passengers who voluntarily or involuntarily were denied boarding due to overbooked flights.  

The report is publicly available
also includes consumer complaints to the DOT in all these areas, which can be made in writing, by phone, through the agency's website, or using the DOT's mobile application.
It is frequently used as a resource for customer service research. 

"Airlines spend tens of millions of dollars trying to make sure their schedules are constructed in such a way that they can meet the DOT definition of being on time, because they don't want to be in last place in that column when the list comes out each year," Wittman says. "So airlines are paying attention to this [data]."

'No good headline' from complaints

After compiling airline service-quality data from 2002 to 2012, Wittman performed a regression analysis to determine the relationships among different variables, such as how the number of bags lost by an airline in a given month relates to the number of complaints issued on the subject. He then charted the performance of 14 major airlines in 12 categories of service failures over a decade.

The data showed that while network carriers provided slightly worse service in some years than low-cost carriers, in general, both types of airlines misplaced a similar proportion of bags, and had similar numbers of flight delays and overbooked planes. But despite comparable levels of service, network carriers such as United Airlines and US Airways received disproportionately more complaints than smaller, cheaper airlines, like JetBlue and Southwest Airlines, even when Wittman controlled for differences in service quality.

Wittman observed a particularly stark difference between United and Southwest: Over 10 years, United received up to 10 times more complaints than Southwest regarding mishandled baggage, even though, empirically, the two airlines had similar rates of baggage-service failures.


Maybe it's the Wild Turkey or maybe it is the sense of humor in the culture, but the contrast is indicative of a larger problem also. There is a reason new pilot openings get 7,000 applications at Southwest and United pilots prefer to go on strike.

And Southwest is cheaper. If you pay more to fly on United, and pay to check your bags, you want things to go smoothly. People expect more quality when they pay more money, that is why United says it charges more money.

Complaint rates may also swing in response to significant events. From 2002 to 2012, the DOT complaint rate ranged from one to three complaints per 100,000 passengers — about the number of customers that fly out of Boston's Logan International Airport in an average day. From aggregate data dating back to 1990, Wittman found that the overall complaint rate fell in the wake of the terrorist attacks of Sept. 11, 2001, and peaked in years such as 2007, when the U.S. air transportation network experienced congestion following an economic downturn that forced airlines to downsize their fleets.

Wittman says that to get a more comprehensive view of how consumer perceptions relate to actual service quality, it would be ideal to look through complaints submitted directly to individual airlines. But such information is proprietary.