A Hawaiian Airlines jet sits at Oakland International Airport on April 8, 2011.
By Ben Mutzabaugh, USA TODAYA Hawaiian Airlines jet sits at Oakland International Airport on April 8, 2011.
Data released Tuesday by the Transportation Department's Bureau of Transportation Statistics on the 16 biggest U.S. airlines show that:•Nearly eight in 10 flights, 79.6%, arrived at gates within 15 minutes of their scheduled time during 2011. That's down slightly from 79.8% the previous year, but still the fourth highest for any year in the 17 years with comparable numbers. •Airlines had their best December in 17 years. Flights arrived on time 84.4% of the time, and 0.8% of flights were canceled. In December 2010, 72% of flights were on time, and 3.7% were canceled.•There was less chance that bags went awry, with 99.7% of fliers getting bags on time. Overall, the rate of mishandled baggage fell to the lowest on record in 2011, falling to 3.39 per 1,000 passengers from 3.51 the previous year.•Fewer passengers were bumped from their flights last year. The rate for bumping passengers was 0.81 per 10,000 passengers, down from the 1.09 rate in 2010. That's the lowest since 2002.Despite the performance, the Transportation Department got 3% more complaints against U.S. airlines in 2011 than the year before. Fliers lodged 9,425 complaints about service, which some analysts attribute to fewer flights and more crowded planes.Crowded planes can mean greater competition for storing carry-on luggage or passengers having to pay extra fees to check their bags."Since you have fewer flights, the flights going out have much higher load factors than people are used to," says Addison Schonland, partner in AirInsight.com, which tracks the airline industry. "Everything is more constrained."December is typically full of delays and cancellations because of weather and a high number of fliers. But it was calm by most standards. Winter weather was milder, and there were fewer service complaints than the year before.Aware of the damage flight disruptions can do to their reputations, airlines have stepped up efforts to improve performance. Delta, for instance, went from eighth-most-on-time airline in 2010 to third last year, thanks to improved customer service training, expanded maintenance stations at key airports and updated technology, the airline says.But flight cutbacks because fewer are traveling may have contributed to fewer delays, analysts say. "The air-traffic control system was busting at the seams in 2005 and 2006," says Rick Seaney, co-founder of FareCompare.com. "It's sort of like having tollways with 90% the previous traffic. You are going to have fewer traffic jams."No domestic flights stayed on tarmacs longer than three hours in December, and no international flight stayed on the tarmac for more than four hours. Federal law prohibits airlines from keeping passengers in planes on tarmacs for longer than that, which some analysts say makes airlines more likely to cancel flights. Year over year, flight cancellations were up slightly in 2011.At the same time, fewer passengers were bumped from their flights last year. The rate for bumping passengers was 0.81 per 10,000 passengers, down from the 1.09 rate in 2010.In December, the airlines with the best on-time performance were AirTran Airways, which is merging with Southwest Airlines, Hawaiian Airlines, which benefits from favorable weather, and Delta. The carriers with the worst were Frontier Airlines, ExpressJet Airlines and Continental Airlines, which is merging with United Airlines.For more information about reprints & permissions, visit our FAQ's. To report corrections and clarifications, contact Standards Editor Brent Jones. For publication consideration in the newspaper, send comments to letters@usatoday.com. Include name, phone number, city and state for verification. To view our corrections, go to corrections.usatoday.com.