Airline performance up in July, 77.6% of flights arrived on time

— -- U.S. airlines' on-time arrival rate of domestic flights improved in July from a year ago as they cut back on routes and seats, according to a monthly federal report Tuesday.

The 19 largest carriers reported an overall on-time arrival rate of 77.6% in July, higher than both the 75.7% of July 2008 and June's 76.1%, says the U.S. Department of Transportation's Bureau of Transportation Statistics. Nearly 40% of all delays were caused by bad weather.

The improvement came on the heels of the carriers' aggressive cutting of flights in recent months amid sluggish demand. In July, 580,000 flights were scheduled, 8% fewer than last year's 628,000.

Among the major carriers, Alaska Airlines was the best performer, with 87.2% of flights arriving on time. AirTran was the worst, with 69.7%.

The carriers also canceled nearly 7,000 flights during the month, or 1.2% of their total operations. They also reported 164 flights that had tarmac delays of 3 hours or more, including 29 that taxied for four hours or more before departing or returning to the gate. US Airways (34 flights with 3 hours-or-more tarmac delay), Delta (26) and JetBlue (24) were the worst offenders.

Among other findings:

•Longest tarmac delays. A July 26 Delta flight from New York JFK to Portland, Ore., sat on the runway for 6 hours and 32 minutes before returning to the gate, the longest tarmac delay of the month.

The longest flight delay occurred in Philadelphia International also on July 26, when a US Airways flight bound for Palm Beach, Fla., sat on the runway for 4 hours and 20 minutes before departing.

•Mishandled baggage. The airlines posted a rate of mishandled baggage of 3.98 per 1,000 passengers in July. That was an improvement over the July 2008 rate of 4.87 and June's 4.17.

•Customer complaints. The department received 827 complaints from consumers about service in July. That's down from 1,093 complaints in July 2008 but higher than 747 received in June. Delta received the most with 130.