Bad Times at the Airport

You can't make flights arrive on time, but you can plan your travel schedule to avoid the worst places and hours.

The government has released another report about airline on-time performance, and it's both horrifying and monotonous.

According to the latest U.S. Department of Transportation survey, just 71.1 percent of the nation's flights arrived on time in August. That's down almost 5 percentage points from August 2006, continuing the yearlong decline in airline efficiency. Cumulative, year-to-date on-time airline performance is the worst it has been in 13 years. Then there's this: 159 flights in August spent more than three hours on the nation's runways waiting to takeoff. Three flights sat on the tarmac for more than five hours.

I have no silver lining to offer here. Things are bad and getting worse.

But while there's no good news, at least there is a copious amount of data to help you protect yourself and minimize your delays. You can spend ages poring over the 44-page D.O.T. report ( http://airconsumer.ost.dot.gov/reports/atcr07.htm), or you can just use my cheat sheet. I've dissected the D.O.T.'s numbers and added some thoughts about the best and worst times to fly into the nation's busiest airports.

Atlanta

On average, almost one in three flights arrive late to Hartsfield airport, where both Delta Air Lines and AirTran Airways operate hubs. Your best shot for an on-time arrival is before 2 p.m., when flights run on schedule 77 to 86 percent of the time. Abandon all hope in the evening; between 7 and 10 p.m., the airport's on-time rate is in the low 40s.

Boston

On average, 70 percent of flights into Logan International Airport are on time for the day. Your best window for timely arrivals is 7 to 10 a.m., when 80 percent of flights are on time. From 6 p.m. on, however, you have almost a 50-50 chance of getting in late.

Charlotte, North Carolina

US Airways dominates Charlotte-Douglas International, where the average daily on-time rate is about 73 percent. Arrive before 3 p.m. and you're in great shape. After 4 p.m., however, Charlotte deteriorates; 6 p.m. to 8 p.m. is worst, with on-time arrivals at about 60 percent.

Chicago

O'Hare International, a hub for the nation's two largest airlines, American and United, is a lousy place to fly. On average, one in three flights run late throughout the day. If you can get in before 10 a.m., you're least likely to be delayed. But after 7 p.m., every other flight arrives late. The situation is slightly better at Midway, where 80 to 90 percent of flights are timely before 4 p.m. But four in 10 flights reaching Midway after 6 p.m. are late.

Dallas-Fort Worth

Dallas-Fort Worth, the home of American Airlines, looked good in August, with about 75 percent of arrivals on time. It was much worse earlier in the summer. Right now, you'll be fine before 2 p.m. But avoid arrivals after 8 p.m., when less than 50 percent of flights are on time.

Denver

Denver's freaky winter weather creates havoc at Denver International, but flights are currently running 74 percent on-time. The airport is great for arrivals before 2 p.m. But with two airlines -- United and Frontier -- having their hubs here, evening arrivals are a crapshoot. After 5 p.m., about four in 10 come in late.

Detroit

Northwest Airlines controls Detroit Metro, where 72 percent of flights arrive on time throughout the day. Your best travel time is the 2 p.m. to 5 p.m. window. Try to avoid flights scheduled to arrive after 9 p.m., when performance slumps into the 50s.

Fort Lauderdale, Florida

Fort Lauderdale has the nation's most schizophrenic airport. Arrive before noon and you've got a nine in 10 shot of being on time. Arrive after 8 p.m., however, and you've got a 50-50 shot of being late.