Fed up with flying, complaints from travelers have soared according to a new study. The annual Airline Quality Rankings by Wichita State University and Purdue University show carriers bumping more passengers from oversold flights and delivering service that often leaves customers frustrated.
"Overall, airline travel is still a hassle for most people," said Dean Headley of Wichita State University. "If it's an uneventful experience that's about the best you can hope for."
Headley believes lackluster, sometimes poor service by airlines is leaving many of the more than 700 million people who fly each year with diminished expectations. "Basically, people flying are saying to themselves, just get me there and I'll be happy with that," said Headley.
The Airline Quality Rankings are based on data compiled by the Department of Transportation for its monthly Air Travel Consumer Report. Categories include on-time arrival records, baggage handling complaints, and the number of passengers who are bumped from oversold flights.
2012 Airline Rankings
- Virgin America
- Air Tran
- US Airways
- American Eagle
Complaints Soar in 2012
Last year, the number of complaints about airline service to the U.S. Department of Transportation jumped almost 20 percent.
A total of 11,495 complaints were received by the D.O.T. with nearly a third involving flight problems such as flight delays and cancellations.
United Airlines registered the most complaints. Not surprising since the airline had three major computer outages last year that caused widespread cancellations and delays.
(Read More: United Scratches Dreamliner Off Schedule)
United blamed one the outages on problems integrating the reservation systems of Continental and United Airlines which merged in 2010.
Packed Planes Means More Bumpings
A troubling new reality for those flying is getting bumped from a flight where they already have a ticket. Last year, the number of denied boardings for oversold flights increased as airlines limited capacity and aggressively worked to increase their load factors.
"There are simply fewer free seats to place bumped passengers," said Headley. "So you have a passenger saying, 'Why me? Why am I the one person on this flight getting bumped when I bought a ticket like everyone else?'"
Airlines typically oversell their flights with the expectation a small percentage of those who bought tickets will not make that flight for a variety of reasons.
(Read More: Airlines' Airfare Hikes Not Faring Well in 2013)
With carriers trying to fill every seat and maximize the profit of every flight don't be surprised if the number of denied boardings continues to climb in the future.
More flights on-time, baggage problems drop
There is some good news in the latest Airline Quality Rankings.
More flights took off and arrived on-time in 2012 and the airlines did a better job handling baggage.
Last year, 81.8 percent of flights were on-time in the U.S. An increase of almost 2 percent compared to 2011. Some of that improvement is due to airlines thinning out their schedules and padding the amount of time it takes to make many of their flights.
"I think the experience has actually improved. Flight attendants are much more courteous. Flights leave on-time more often," said James Lowe, a college administrator in Mobile, Alabama who takes a half dozen flights a year.
(Read More: Now Boarding Sooner: Fliers Without Carry-Ons)
Meanwhile, baggage complaints have dropped in part because many fliers have cut back or even stopped checking bags due to fees many carriers now charge.
—By CNBC's Phil LeBeau; Follow him on Twitter: