Delta No. 2 in airline quality ranking, nearing top spot

FILE - In this Jan. 30, 2017, file photo, a Delta Air Lines flight takes off from Hartsfield-Jackson Atlanta International Airport in Atlanta. (AP Photo/David Goldman, File)

Delta Air Lines remained in the No. 2 spot in an annual ranking of airlines, but came in close behind No. 1-ranked Alaska Airlines.

The Airline Quality Rating by researchers at Wichita State University and Embry-Riddle Aeronautical University showed that Alaska Airlines "barely edged out" Atlanta-based Delta for the No. 1 spot, according to the study released Monday.

It was the closest finish in the rating's nearly three-decade history, with only a 0.005 difference in score between Alaska and Delta, according to the researchers.

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Overall, airlines’ on-time performance slipped, but carriers improved their performance in involuntary denied boardings, mishandled bags and customer complaints, according to the Airline Quality Rating. Alaska and Delta both saw performance declines in the study, but still remained in the No. 1 and No. 2 spots.

Dallas-based Southwest Airlines, the second-largest carrier at Hartsfield-Jackson, came in at the No. 5 spot in the Airline Quality Rating.

Last year “was a rough year for the airlines in the public’s eye,” said Embry-Riddle professor and study researcher Brent Bowen. “But the results of the study show that they are making the effort – even if it may seem incremental to the traveling public, the numbers are there.