US Airways' computer problems and wintry weather combined to pull down Philadelphia International Airport's record for airline on-time performance in March and the first quarter of the year. US Airways' troubles also hurt on-time operations at Charlotte, N.C., its largest connecting hub.

The U.S. Bureau of Transportation Statistics reported today that only 60 percent of all major airlines' flights departed Philadelphia within 15 minutes of schedule in March, ranking it No 31 out of the 32 largest U.S. airports. At Charlotte, 57 percent of all flights left on time in the month, putting it in last place.

For arrivals, 59 percent were on time in March at Philadelphia, leaving it in 29th place. Charlotte finished at No. 28, with 60 percent on time.

Through the first three months, 65 percent of Philadelphia flights were on time arriving, and 67 percent departed on time.

Philadelphia did better in 2006, finishing in 14th place with 79 percent of arrivals on time, and in 26th place for departures, at 76 percent.