US aviation regulator calls for checks on older Boeing 737 jets

Unlock the Editor’s Digest for free

Roula Khalaf, Editor of the FT, selects her favourite stories in this weekly newsletter.

The US aviation regulator has recommended that airlines check an older version of Boeing’s 737 jet that has the same kind of door plug as that which blew out on an Alaska Airlines aircraft earlier this month.

The Federal Aviation Administration said late on Sunday that as an “added layer of safety”, it was recommending operators of Boeing 737-900ER aircraft “visually inspect mid-exit door plugs to ensure the door is properly secured”. 

The 737-900ER is an earlier version of the 737 Max 9 aircraft that is at the centre of an investigation following the accident on January 5.

The FAA said that following additional maintenance inspections by some 737-900ER operators of the door plugs on their aircraft after the Alaska accident, they had “noted findings with bolts”. 

It recommended that operators perform “key portions” of the maintenance inspection procedure related to the four locations where a “bolt/nut/pin installation is used to secure the door to the airframe, as soon as possible”.

The agency grounded 171 of Boeing’s 737 Max 9 aircraft while investigations continue into what went wrong, but the incident has already raised questions over Boeing’s quality controls and those of supplier, Spirit AeroSystems, which built the fuselage.

It has also refocused scrutiny of the 737 Max, Boeing’s most popular plane, whose smaller model, the Max 8, was involved in two fatal crashes in 2018 and 2019. 

Boeing has been scrambling to contain the fallout from the Alaska incident. It has brought in a retired Navy admiral, Kirkland H Donald, to review its quality management systems. Important customers, including Ryanair and aircraft lessor AerCap, have in recent weeks warned that the company needs to focus on safety and quality control. 

According to Boeing data, more than 500 of the 737-900ER models have been delivered to airlines globally. Leading operators include United Airlines, Alaska Airlines and Delta Air Lines. The three US carriers fly the majority of the 380 aircraft understood to have the door plug affected by the recommendation.

United said it started “proactive inspections” of its Boeing 737-900ER jets last week and expected to complete them “in the next few days” without disruption to travellers. The Chicago-based carrier has 136 Boeing 737-900ER aircraft in its fleet.

Delta said it also “elected to take proactive measures to inspect our 737-900ER fleet” and it did not expect “any operational impact”.

“We remain in close communication with the Boeing team,” the Atlanta-based airline added.

The door plugs replace mid-cabin emergency exit doors and are installed depending on the configuration used by the respective airline operator. They are common features and have been used on both Boeing and Airbus aircraft for decades.  

Most of the Boeing 737-900ERs subject to the latest FAA directive were delivered between five and 17 years ago and would have undergone detailed maintenance inspections since then, according to industry analysts.  

Boeing said: “We fully support the FAA and our customers in this action.”