Airlines post fewer flight delays in May, government reports

— -- The nation's largest airlines once again delivered passengers and luggage to their destinations on time at a high rate in May.

Airlines posted an on-time arrival rate of 83.3% in May, up from the 77.1% rate in May 2011. It was, however, a slight dip from April's rate of 86.3%, the Transportation Department reported Tuesday.

Flights are considered on time when they arrive within 15 minutes of their scheduled time. In the first five months of this year, they've had the highest on-time arrival rate — 84.3% — for any such period in the 18 years that the department's Bureau of Transportation Statistics has been recording data.

The rate of canceled flights for the five months, which was 1.07%, also was the lowest in the last 18 years.

Airlines have been boasting of more frequent on-time arrivals so far this year, but analysts point out that there have been few major snowstorms or thunderstorms in the last several months. Also, they say, airlines are flying fewer planes and padding their schedules.

"We're not clogging the skies," says Mike Boyd, president of the Boyd Group, an airline consulting firm. "Secondly, we have a situation in which there wasn't much in terms of weather. Why are 16% of flights arriving over their 15 minutes?"

In May, airlines canceled 0.9% of their domestic flights, down from May 2011's 2.1% cancellation rate and April 2012's 1%.

More bags got to their destinations on time. There were 2.77 reports of mishandled bags per 1,000 passengers in May, better than May 2011's rate of 3.54 but up from April 2012's rate of 2.63.

There was only one delay of a flight on an airport tarmac of more than three hours on a domestic flight, and one of more than four hours on an international flight. Airlines are now required to report lengthy waits on tarmacs and let passengers return to the terminal if they're held too long on the plane without taking off.

Despite the improved numbers, more consumers complained about U.S. airlines in May. There were 935 complaints vs. 904 in May 2011.

The airlines with the best rates of arriving on time in May were Hawaiian Airlines, which usually doesn't deal with bad weather, Alaska Airlines and AirTran Airways. Airlines posting the most delays were United Airlines, ExpressJet Airlines and American Airlines.