Airline passenger complaints surged in 2012

WASHINGTON (AP) - Private researchers who have analyzed federal data on airline performance say passengers are getting grumpier, and with good reason.

Carriers keep shrinking the size of seats in order to stuff more people into planes. Empty middle seats that might provide a little more room have vanished. And more people who have bought tickets are being turned away because flights are overbooked.

A report being released Monday says consumer complaints to the Transportation Department surged 20 percent last year even though airlines have been doing a better job by other measures, like on-time arrivals and mishandled baggage.

Dean Headley, a business professor at Wichita State University who has co-written the annual report for 23 years, says the airlines are approaching a point of diminishing returns for their practices.

Some use of larger planes hasn't been enough to make up for an overall reduction in flights.