There’s no shortage of surveys and reports measuring airline performance. Some employ hard data, while others rely more on flier opinions.

Viewed as a whole, though, one thing seems clear: Southwest Airlines does well just about any way you cut it.

That’s significant news for Atlanta fliers now that Southwest plans to buy AirTran Airways and take over its Hartsfield-Jackson International operations. One challenge will be transferring its service chops to the world’s busiest airport, where congestion and delays are more common than at many.

Here are some measures for Southwest, AirTran and Hartsfield-Jackson kingpin Delta Air Lines:

On-Time Flights

For the 12 months ended July 31, Southwest ranked 5th out of 18 airlines with 81.3 percent of its flights arriving on time, according to the U.S. Bureau of Transportation Statistics. AirTran was 11th at 78.4 percent, and Delta was 14th at 77.8 percent. One interesting note: Southwest was No. 1 among eight airlines measured from 1987 through July 2010, at 81.9 percent.

Consumer Complaints

This category, also reported by the BTS, counts complaints to the government regarding flight cancellations and delays, ticketing and boarding problems, fares, lost baggage and other customer service issues.

For July, Southwest had the fewest complaints per 100,000 enplanements -- 0.23. AirTran ranked 4th among the 18 airlines measured with 0.62 complaints. Delta ranked 17th with 2.44 complaints.

Reward Seat Availability

A major gripe for some frequent flyers is the difficulty of getting reward seats. IdeaWorks, a consulting firm, this year released its survey of airline reward seat availability. It measured availability for June through October 2010.

Southwest’s Rapid Rewards program ranked first with 99.3 percent availability. AirTran’s program ranked 13th with 67.9 percent availability. Delta ranked 21st of 22 airlines measured with 12.9 percent availability. Delta said it’s hard to compare airlines and that it offers more availability for elite frequent fliers.

Customer Satisfaction

The American Customer Satisfaction Index, founded by a partnership including the University of Michigan, releases reports on service industries including airlines. Findings are based on customer interviews.Among carriers in its last report, Southwest ranked first. Delta tied for fourth. AirTran wasn’t included.

Customer Satisfaction II

Another report comes from marketing information services company J.D. Power and Associates. The firm measures satisfaction with major airlines among both business and leisure travelers over a year-long period.

The J.D. Power survey has two categories: low-cost or traditional carrier. Southwest ranked second among low-cost in the 2010 survey, behind JetBlue Airways. AirTran came in fourth. Delta was fourth among traditional carriers.