AirTran led the pack in the newest annual Airline Quality Rating report, switching places with last year's leader Hawaiian. JetBlue remained at third while Alaska jumped to fourth from eleventh in the ranking. Southwest ranked fifth.
Overall performance of leading U.S. air carriers has improved for the third straight year, the report found. The number of customer complaints was up, the only one of four major areas which saw a deterioration in quality.
The annual Airline Quality Rating report showed gains in the three other areas: on-time performance, baggage handling and involuntary denied boarding.
Among the three biggest airlines in terms of traffic, No. 2 Delta made the biggest improvement, leaping to seventh from 15th -- the largest movement in the list of 16 airlines.
No. 1 carrier United ranked 12th and No. 3 American 11th, with its regional carrier American Eagle finishing last at 16th. US Airways notched up to sixth from eighth.
"It is clear that the low-fare carriers have a better philosophy about execution and better employee engagement in that execution than most of the other airlines," Dean Headley, an associate professor at Wichita State who worked on the study, told Reuters by telephone.
The overall score for the industry was the third best in 20 years of tracking, a statement from Wichita State University and Purdue University said.
The Airline Quality Rating is a joint project funded as part of faculty research activities at the two schools.
Regarding the higher number of customer complaints, Headley linked it to busier air travel.
"As the system adjusts to higher demand for air travel, more things are not going to go as planned for travelers," Headley said.
The release of the report coincidentally came on a day when one major carrier, Southwest Airlines, canceled 70 flights as it continued to inspect Boeing 737 planes following the emergency landing on Friday of a jet with a hole in its fuselage.
The AQR evaluates published, publicly available data on performance and combines them into a rating system.
The individual rankings, from top to bottom, follow:
6. US Airways
15. Atlantic Southeast
16. American Eagle