Delta details airfare glitch

Delta is the largest airline serving Charleston International based on passenger volume. File/AP/John Bazemore

MINNEAPOLIS — Delta Air Lines said a glitch that appeared to show different airfares to frequent fliers happened because it was trying out a new company to power flight searches on its website.

The airline has taken heat from customers after reports that people who logged into its website with their frequent flier number were offered higher fares than those who searched anonymously. Frequent fliers are an airline’s most-valued customers, and the idea that they were asked to pay more has rankled travelers.

Late Friday afternoon, the Transportation Department said it is “looking into the Delta pricing issue.” Spokesman Bill Mosley refused to elaborate.

The airline, the largest serving Charleston International Airport, offered its first detailed explanation of what went wrong in an interview with The Associated Press on Friday.

Delta and other airlines use third-party companies such as Google’s ITA Software to deliver results when customers search for flights. Those search providers sift through all the available seats, possible connecting flights and different fares to show flight options to customers.

Delta was thinking about switching search providers, so starting on April 20 it ran a side-by-side experiment, Bob Kupbens, the airline’s head of e-commerce told The Associated Press. People who logged in with their frequent flier number saw results from the airline’s current search provider. People who searched anonymously got results from the experimental provider. Delta declined to name either company.

“We don’t want to take all of our best customers, who we care the most about, and put them immediately onto a new search engine,” Kupbens said. Ultimately, he said, the airline hoped the switch in search companies would provide travelers with faster and more-relevant search results.

The problem was that one of the search engines included flight possibilities that the other one didn’t, Kupbens said.

For example, one search might include a cheaper flight with a less-desirable connection, while the other one didn’t include that option. A customer would see that one result had cheaper options than the other.

Kupbens said the airline never sold customers the same exact roundtrip flights at different prices.

“To be clear, we never — and couldn’t have, based on the technology — we never sold the exact same itinerary for a different price. So what customers were seeing was a difference in search results, not a different price for the same itinerary,” he said.