Why is there no Terminal D at Logan Airport?

It doesn’t take a frequent traveler to notice that the list of terminals at Logan International Airport jumps from A, to B, to C, to… E?

No, the lack of Terminal D is not an error on Logan’s part. And as far as mysteries go, this one is pretty straightforward.

The Massachusetts Port Authority, which operates Logan, removed Terminal D in 2006 in an effort to “reconfigure the area and modernize the space to make it more passenger-friendly,” the Massport spokeswoman said. , Samantha Decker, to Boston.com in an email. The old Terminal D gates have been renumbered and absorbed into Terminals C and E, Decker confirmed.

A 2006 Massport press release noted that Terminal D was more of an annex to Terminal C anyway, with its three gates being used by Air Tran Airways, a low-cost airline since acquired by Southwest Airlines. Nixing Terminal D asked Massport to update Logan’s pre-recorded announcements and replace nearly 200 signs in terminals, garages and roadways, according to the statement.

“This is part of a larger effort to help Logan passengers navigate the entire airport,” Massport’s then-chief aviation manager, Thomas J. Kinton Jr., said in the statement. . “Customer surveys indicate that a more efficient and understandable terminal layout would make getting around the airport easier and more user-friendly.”

Massport originally planned to wait a year before knocking on Logan’s international gateway, Terminal E, a letter in the alphabet. The Boston Globe reported at the time that the break was intended to help Massport avoid confusion.

“The move from E to D overnight, they feared, could lead to some Logan veterans heading for an international flight only to stop at the AirTran gates, known as Terminal D for more than 25 years,” said the World reported.

However, Massport ultimately scrapped plans to rename Terminal E due to high signage update costs, Decker explained.

“At that time, the signage was not digital, so it was more complicated to replace them,” she wrote.

Boston.com asked Massport if the lack of Terminal D is confusing travelers, especially those who aren’t from New England.

Decker’s answer? “No.”