Philadelphia International Airport's on-time record soared in April compared with a year ago, boosted by the performance of US Airways Group Inc.

Overall, the U.S. airline industry had the best on-time rate for any April since 2003 because of fewer delays linked to weather and traffic volume, the U.S. Department of Transportation said Thursday.

"This was the second-best April for the past 16 years with comparable data," DOT spokesman Bill Adams said.

It was also Philadelphia's best April since 2003. Arriving flights were on time 85.9 percent of the time, an improvement from 70.7 percent in April last year.

Departures had an 87.9 percent on-time record in April, up from 77.1 percent in April 2009, according to the DOT's Air Travel Consumer Report.

Philadelphia International ranked 15th in on-time arrivals (up from 26th a year ago) and ninth in on-time departures (up from 23d) among 29 major airports in the survey. April is the most recent month for which statistics were available.

US Airways, which carries two-thirds of Philadelphia's passengers, ranked third among 18 U.S. airlines, with on-time arrivals of 88.6 percent.

Two smaller carriers, Hawaiian Airlines Inc. and Alaska Air Group Inc., topped the list.

On-time means an arrival or a departure less than 15 minutes after the scheduled time.

How an airport ranks in a given month can depend partly on weather - thunderstorms, wind, fog, snow, and ice.

"April was a mild month, with warmer-than-normal temperatures, and a little drier than normal," said Gary Szatkowski, meteorologist at the National Weather Service in Mount Holly. "We had precipitation at the airport on 14 of the 30 days, but the amounts were relatively light."

Airlines have reduced capacity - seats and flights - which has eased traffic volume somewhat. Still, Philadelphia is in heavily congested East Coast airspace.

Reports of mishandled baggage by US Airways improved in April to about 2.07 reports per 1,000 passengers, from 2.88 reports a year ago.

US Airways, based in Tempe, Ariz., ranked 15th in customer complaints among the 18 carriers. US Airways logged 67 complaints in April, a rate of 1.55 per 100,000 boarding passengers, compared with 61 complaints, or 1.35 complaints per 100,000 boarding passengers in April 2009.

Also Thursday, US Airways reported improved revenue and passenger demand in May. Passenger traffic rose 1.8 percent, and passenger revenue per available seat mile - a ratio of revenue to capacity - jumped 18 percent from May 2009.

Continental Airlines Inc., American Airlines, and Delta Air Lines Inc. reported stronger traffic in May than a year ago, a sign that the industry may be recovering from the recession.