DOT statistics released for the first half of 2011 show United, US Airways and Continental Airlines, take the top three spots for complaints about major airlines.

While overall complaints are down compared to the same time last year, they’ve only decreased by 400. Much of that is attributed to Twitter and Facebook, with some airlines staffing customer service groups dedicated to handling such complaints, and some like SkyWest that maintain a Twitter page, but appear to use it only as a way for visitors to bookmark and find the company’s main website.

As usual, top complaints were poor customer service, flight delays, and baggage problems. Continental had a significant increase in customer service complaints, and some say it is due to the merger with United, who routinely ranks the worst in customer service of the major airlines. The bad traits of United seem to be “rubbing off” on Continental. Continental used to have the lowest customer service complaints of the major airlines.

Next on the list at #4 is American Eagle, plagued with constant flight cancellations. It ranks as the absolute worst in both flight delays and cancellations of any regional carrier. Recently, American Airlines announced they intend to spin off or sell their regional carrier component.

Coming in at #5 is American Airlines, though considerably lower than any of the top 3. American has deployed an army of Twitter complaint takers, who have worked to cure problems before they become complaints and it seems to be paying off.

#6 is Delta, which also claimed the title of the most improved airline from last year.

The rest of the pack of most complaints about airlines come in a distant 7-16. The remaining spots in the top 20 belong to foreign air carriers.

#7, JetBlue
#8, ExpressJet Airlines. ExpressJet was ranked separately because it is still in the process of its merger with ASA. Or should we say Surejet or no wait, they dropped that name change. XJT flies mostly for Continental Airlines. It rose on this list and some blame the lower wages imposed on employees following the merger with ASA who has a lower pay scale, saying morale has crash landed.
#9, Atlantic Southeast, (ASA). Ranked sperate from its parent airline, SkyWest, because they fly mostly in different parts of the country and for different airlines.
#10, SkyWest, based in St. George, Utah, flies mostly for United and Delta.
#11, Hawaiian Airlines. The airline recently purchased new A330’s for serving longer routes and added new routes.
#12, Frontier Airlines, based in Denver, is owned by Republic Airway Holdings.
#13, Airtran Airways, recently bought by Southwest, is currently headquartered in Orlando, Florida.
$14, Mesa Airlines
#15, Alaska Airlines
#16, Southwest, most of its complaints are largely around the condition of its aircraft; the airline operates one of the oldest fleets of any major U.S. carrier with its fleet averaging 15 years old.

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