A stowed secondary cockpit barrier on a Southwest Airlines 737.

Southwest Airlines passengers will soon begin seeing a new security device on the carrier's newest Boeing 737s. The airline announced Friday that its first plane with secondary cockpit barriers had gone into service, and Southwest expects to have 26 aircraft fitted with the device in service by the end of the year.

“This requirement actually goes all the way back to Sept. 11. Following that event, it was always looking for a path to make the flight deck more secure," Southwest Executive Vice President of Operations Justin Jones told USA TODAY. "It’s just another layer of protection there to make sure no passengers who aren’t supposed to be in the flight deck ever get into the flight deck.”

The device is a fold-away door on the cabin side of the forward galley. According to Jones, flight attendants will deploy it when a pilot exits the cockpit to use the lavatory or for any other reason. The barrier will be opened again once the cockpit door is closed, meaning it will only be deployed for seconds at a time on any given flight.

Before the installation of the secondary cockpit barriers, Southwest Airlines' procedure required a flight attendant to stand and face the cabin while a beverage cart was used to block passengers from approaching the galley.

“The same procedures will be followed, but they’ll close a secure door there,” Jones said. “Personally, I think it will be a better customer experience," because it will be clearer to customers that the area is off limits while the cockpit door is open.

The requirement for secondary cockpit barriers was part of the Federal Aviation Administration's response to the Sept. 11 attacks, but was only passed in 2023. The FAA has given airlines the option of waiting until they get new planes with the devices delivered, and there's currently no requirement – or approved – option for retrofitting aircraft that are already in service.

The Air Line Pilots Association, the largest pilots union in the U.S. has long supported the measure and has repeatedly called on airlines to implement the barriers "without delay."

American Airlines, Delta Air Lines and United Airlines were not immediately able to provide USA TODAY with details on their plans to implement secondary cockpit barriers.

(This story was updated to refresh headlines.)

Zach Wichter is a travel reporter and writes the Cruising Altitude column for USA TODAY. He is based in New York and you can reach him at zwichter@usatoday.com.

This article originally appeared on USA TODAY: Take a look at Southwest's newly installed fold-away cockpit barriers

Reporting by Zach Wichter, USA TODAY / USA TODAY

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