FAA asks airlines to inspect earlier generation of Boeing 737s after mid-flight blowout

The Federal Aviation Administration issued a new safety alert for airlines who fly an earlier version of the Boeing 737 to inspect the mid-exit door plugs after one blew out during an Alaska Airlines flight earlier this month. 

The FAA said Sunday that it is recommending that operators of Boeing 737-900ER aircraft "visually inspect mid-exit door plugs to ensure the door is properly secured." The agency added that Boeing 737-900ER is not part of the newer MAX fleet – but has the same door plug design. 

The agency called the recommendation "an added layer of safety."

Alaska Airlines Flight 1282 was forced to make an emergency landing on Jan. 5 in Portland after a plug covering an unused exit door blew off the Boeing 737 Max 9 as it cruised about three miles over Oregon. 

A plastic sheet covers an area of the fuselage of the Alaska Airlines N704AL Boeing 737 MAX 9 aircraft outside a hangar at Portland International Airport on Jan. 8, 2024, in Portland, Oregon. (Photo by Mathieu Lewis-Rolland/Getty Images)

While none of the 171 passengers or six crew were seriously injured, the rapid loss of cabin pressure caused oxygen masks to drop from the ceiling and caused a chaotic scene on board. 

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The NTSB is investigating the accident, while the FAA investigates whether Boeing and its suppliers followed quality-control procedures. 

Alaska and United Airlines, the only other U.S. airline that flies the Max 9, reported finding loose hardware in door plugs of other planes they inspected after the accident. Both airlines have canceled hundreds of flights while their Max 9s are grounded.

The Max is the newest version of Boeing’s 737, a twin-engine, single-aisle plane that debuted in the late 1960s and has been updated many times. The 737 has long been a workhorse for airlines on U.S. domestic routes.

The 737-900ER is not part of the newer MAX fleet but has the same optional door plug design, allowing for the addition of an extra emergency exit door, according to Reuters.

A total of 490 Boeing 737-900ER jets are in service, including at least 79 that have an active door rather than a plug because they are operated by low-cost airlines with denser cabins, Reuters reported, citing data from aviation analytics firm Cirium.

Meanwhile, FAA officials last week briefed a congressional committee on their investigations, which remain in the early stages, and revealed that airlines have inspected 40 Boeing 737 Max 9 jets. The FAA said it would review information from those inspections while it develops a maintenance process before letting the planes carry passengers again.

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Boeing, which has had problems with various planes over the years, has pledged to "help address any and all findings" that airlines make during their inspections of the jets.

This story was reported from Cincinnati. The Associated Press contributed.