With news of more 737-9 aircraft possibly having loose bolts in their mid-cabin door plugs, Boeing starts 2024 in the worst way possible.
It is two days since an Alaska Airlines Boeing 737-9 lost a door plug, as it climbed through 16,000 feet. This was Alaska Air flight 1282, departing from Portland International (KPDX), heading for Ontario International (KONT).
As we’ve already seen, the aircraft suffered an explosive decompression, when the left waist-cabin door plug was somehow separated from the rest of the aircraft. The NTSB confirmed that an individual found the door plug after it landed in his backyard!
Thankfully, while some passengers in the Alaska flight required medical attention, it appears that nobody suffered serious injuries. Also, the door didn’t hit anyone on its way to the ground. A good thing, since it weighs approximately 60 pounds (27 kilos).
There was also some amusing news in this affair when someone recovered an iPhone that had fallen from the aircraft, and which didn’t have so much as a scratched screen. But for Boeing, the immediate repercussions of this 737-9 door plug issue could hardly be more serious.
Boeing 737-9 Door Plug – A Description
A “door plug” is still a door, with the normal hinges and other components that engage into the frame, to hold cabin pressure. What the door is missing is the latching/release mechanism, along with a vent to depressurize the cabin in an emergency, before opening.
Instead of the opening mechanism, the door plugs of these Boeing 737-9 single aisles have four bolts, secured using safety-wired nuts. Airlines (including Alaska and United in the U.S.) use such door plugs in the mid-cabin door positions of their Boeing 737-9 fleets, since these planes have fewer than 189 seats.
The door plug has a regular passenger window, unlike the porthole of the functional emergency exit, and no handle or other indication that there is a door behind the wall. Both the NTSB and the FAA are investigating this serious incident.
Checking for proper installation of these door mechanisms’ bolts and other attachments reportedly takes around four to eight hours per aircraft. But initially, the FAA was waiting on Boeing to prepare paperwork for the inspection.
Boeing took some time to prepare this paperwork, which the FAA then approved. This cleared the path for operators of Boeing 737-9 aircraft with door plugs to inspect them and return them to service.
More Planes With Loose Bolts?
Worryingly, The Air Current reports that United Airlines found loose door fittings on at least five aircraft in its Boeing 737-9 fleet. At this time, we don’t know how old these jets are and how long they have been flying in this condition.
But there is no question that this matter is giving Boeing a black eye – and it comes at a lousy time. Boeing is on the verge of getting certification for its 737-7, the smallest MAX variant. It has recently begun flight testing the larger 737-10 with FAA pilots, plus it is looking for an exemption in the 737-7 certification, involving engine anti-icing.
Meanwhile, Boeing is also keen to resume deliveries of new 737s to customers in China, at a time when geopolitics is beginning to look more favorable for the manufacturer. And finally, there is the flight testing and certification of the 777X.
So no, this 737-9 door plug issue is not what Boeing needs right now. We have recently seen that Boeing and tier-one supplier Spirit AeroSystems dealt with two quality control issues last year, affecting 737 production.
This new issue is refocusing the public’s attention on Boeing’s relationship with its supplier. Restoring public confidence has been a moving target for Boeing. Unfortunately, there still seems to be some way to go on that front.