INCIDENT: Alaska Air 737 MAX-9 Loses Plugged Door In Flight

By Spyros Georgilidakis | January 6, 2024

Alaska Airlines announced that it is grounding all of its 737 MAX-9 aircraft for inspections after a plugged passenger door failed in flight.

This extraordinary event happened on Friday the 5th of January, on Alaska Airlines flight AS-1282. The flight is a regular domestic service, departing from Portland International Airport (KPDX) in Oregon, USA, at 4:40 PM. Its destination is Ontario International Airport (KONT) in California.

INCIDENT: Alaska Air 737 MAX-9 Loses Plugged Door In Flight
Another Alaska Air 737-9. Photo: Sam Almo-Milkin, CC BY-SA 4.0

On the day of this plugged door incident, Alaska used a 737 MAX-9 for the flight. The aircraft had 171 passengers and 6 crew on board. The flight was about 25 minutes late, when its crew took off uneventfully, using runway 28L in Portland.

Initially, the flight climbed normally, making a left turn as they turned south toward California. But the Alaska flight crew stopped climbing as they were passing 16,000 feet. Some passengers reported that a section of the wall in the cabin appeared to blow out.

A Safe Return

Thankfully, it appears that the seat that was closest to this plugged door of the Alaska MAX-9 was empty. Obviously, this caused a cabin decompression, so the Alaska flight crew descended to 10,000 feet.

They didn’t sit there for long. They soon continued their descent, as they set up an approach back on runway 28L in Portland. The flight landed safely, having spent about 20 minutes in the air. There are NO reports of any injuries. Alaska Air rebooked the passengers on a 737-900ER, which has the same door configuration as the MAX-9.

INCIDENT: Alaska Air 737 MAX-9 Loses Plugged Door In Flight
Photo: @JacdecNew via X (formerly Twitter)

The incident aircraft is essentially a brand-new Boeing 737-9, with registration N704AL. It first flew on the 15th of October last year, with Alaska taking delivery of it later the same month. Alaska Airlines has 65 of these jets.

In Alaska service, the 737 MAX-9 or (737-9) has seats for 178 passengers, which explains why this door wasn’t in use. 737s with 190 or more passenger seats need these extra doors (plus other provisions) for evacuation purposes.

INCIDENT: Alaska Air 737 MAX-9 Loses Plugged Door In Flight
Photo: @JacdecNew via X (formerly Twitter)

Alaska MAX-9 Fleet And Door Layout

But airlines that fit fewer seats can deactivate these doors. This is what Alaska is doing on its 737 MAX-9 fleet because the plug is lighter than a normal door. From the inside, there is little to indicate that this is a door opening – apart from the odd spacing between the passenger windows.

This arrangement is not unique to Alaska or even to Boeing aircraft. Many Airbus A321s worldwide have similar-looking plugs on the doors immediately behind the wing. An aircraft manufacturer can install such plugs if the airline wants them. But airlines can re-activate the doors at a later date, if necessary.

Do you see it? There is a deactivated door on the side of this Delta A321neo. Photo (cropped): MarcelX42, CC BY-SA 4.0

After the event, Alaska Airlines announced that it is grounding its MAX-9 fleet temporarily, presumably to inspect the installation of these door plugs. The airline states that it should be able to complete these checks over the next few days.

According to the Air Current, Alaska crews flying this specific aircraft got indications of a pressurization issue on at least two occasions, the day before the incident. The airline couldn’t immediately identify the cause of the problem.

INCIDENT: Alaska Air 737 MAX-9 Loses Plugged Door In Flight
Alaska’s older 737-900ER models have the same door arrangement. Photo: Jeffry Surianto

The FAA and the NTSB have stated that they are aware of this event and that they will be investigating. Boeing also announced that “A Boeing technical team stands ready to support the investigation”.



  • Further to my recent comment about the 737’s bad reputation from the very earliest models qualifying it to be labelled a flying coffin and death trap that should be relegated to the bone yard for scrapping, a You Tube video yesterday quoted a Boeing employee as describing the 737’s production as being “assembled by clowns and supervised by monkeys”!! So the truth be told by those that personally know of Boeing’s blunders directly on the scene of the factory floor itself.

    (This is based on my own thorough research from multiple reputable online sources, it took me a couple of days of research)

    I found out that the plug is an option also 737-900ER with airlines like Alaska, United and Delta flying hundreds of them with this plug option, that I assume is the same as the one installed in the 737-MAX-9 like the Alaska accident plane.

    Why, then, is the FAA not mandating inspection of all 737-900ER fitted with the plug option too? I am trying to raise awareness on this especially in influencing people that have worldwide visibility and access to good sources (like Mentour) with the hope that a) they can ask the FAA directly and b) they can raise awareness in the public, hopefully adding pressure to the FAA.


    There is a guy called Chris Brady. He is a hands-on expert in everything 737.
    He has a site called “The Boeing 737 Technical Site” which is excellent:
    I have been following this site for years, but I have just discovered his also excellent youtube channel in the wake of this Alaska blown plug accident.
    He has 2 excellent videos on this door and plug:

    In that video, he says (or at least that’s what I understood) that the different options for that exit are:
    a) Emergency exit door with various certification rating options.
    b) Inactivated emergency exit door.
    c) Door plug.

    From his explanation, I thought I understood that the plug option (c):
    a) Is the only option with a full-size passenger window
    b) Is available only in the 737-MAX-9 (not in the -900ER, not in the -MAX-8200, not in the -MAX-10, and of course not in any other variant that doesn’t even have the opening in the fuselage)

    However, this picture shows an Alaska 737-900ER with a door that has a full-size passenger window.

    Further looking at pictures and seat maps I found that:
    For Alaska, United and Delta, both the 737-900ER and the 737-MAX-9 have fewer than 189 seats (max evacuation limit without the mid-cabin emergency exit), have no emergency exit row and have a panel with a full size window, no handle and no pressurization equalization vent, indicating that it is a plug and not a deactivated door (deactivated door has no window because the porthole window is plugged, and it has the handle and the vent).

    As a contrast, check this picture from a Lyon’s 737-900ER

    This one seats more than 189, has an emergency exit row there, and the panel features the porthole window, handle, vent and a painted door layout (the layout is not there either in the plug or the deactivated door options).

    And if you check seat maps and pictures of United, Alaska, Delta and Lyon 737-MAX-9 planes, you find exactly the same coincidences and differences as above for the -900ER.

    So what United, Delta and Alaska have in their 737-900ER HAS to be a plug.

    Information found here
    reveals that Boeing delivered almost 150 737-900ER during the last 5 years of production (2015-2019), almost ALL of them (except 10 or so) to United, Delta and Alaska surely featuring the plug door.

    I exchanged emails with Chris Brady and he confirmed that the 737-900ER also has the plug option. He could not confirm yet that it is the same design but he strongly suspects it is. And I do too (it is the same fuselage, just lengthened a little bit).

    So given that the latest -900ER were delivered more than 4 years ago and most of them must have thousands of flight cycles each with such an incident with the plug door never happening, I might understand the FAA not immediately grounding the -900ER. But how about a very short term mandatory inspection? Like give them 1 month.

  • Hi, I just have watched this
    Youtube video. What can be said about the allegations made by a former Boeing Manager in this video. To be honest it soudn terrifying. If this company feela the pressure to cut costs, and therefore sacrifices quality control. This is alarming and I will not step foot into a boeing aircraft anytime soon.

  • Regulations should change, and customers should be aware of issues with their plane to decide whether to fly with that particular plane or not.

  • geoffrey nicholson


    Have you seen this description of the technical construction and operation of the B737 – Max 9 plug door?

  • Conspiracy? Personally I don’t think so. The fact that we are externalizing almost all operations in order to cut some expenses it is quite alarming. Management stress because of the non certification of the MAX 7? Guys, Boeing issued an exemption for a safety certification on MAX 7 until 2026 for the de-icing system. This is unacceptable and dangerous, that’s why this plane is still not certified and in my opinion it will be not certified until Boeing is not fixing on it this issue. Actually the “ball” is in the Boeing’s courtyard and not in the FAA’S. I don’t know what happened to Boeing, being myself an Airbus customer support engineer, I use to love those Boeing marvels, but not anymore….sad…really sad.

  • Helio Luchtenberg Jr

    Conspiracy against Boeing from their own workers?!
    Do not make laugh, this is not fun at all.

    When the two fatal crashes of 737-MAX 8 happened, Boeing’s CEO took no time to put the guilty on the pilots, without no proofs or investigations.

    In the end it was concluded that it was a design flaw (read: too many design flaws) responsible for that.

    In the 2000’s I have flied dozens of times, and had no fear of flying. But now, in the 2020’s, after some years of studying the overall situation of aviation in the world, and following everything related, I have fear of flying. It is because now I have a clearer idea of the thousands of risks involved.

    Now, I avoid flying at all. I will consider flying again only in case of fleeing my country if a war explode here in Brazil. Only to save my life from a sure death on the ground.

    That is pitty because Boeing alone destroyed all the reputation of pilots/airlines/mechanics/airports and people who build and design such airplanes.

    I will always folow Mentour Aviation and everything I can.
    Thank you all for you existing.

  • The enlightened, rational part of my brain knows each of these Max issues will be addressed in turn. The primative cave-dwelling part though genuinely feels the sky gods are angry with Boeing and won’t let me fly on anything they’ve built in the last 5 years… 🤷‍♂️

  • Here we are now confronting yet another flight failure of the I’ll fated Boeing 737 Max breed of jinxed and cursed aircraft! Past tragic incidents involving sudden uncommanded rudder hard overs and MCAS software failures causing fatal nose dives and worldwide groundings have cost more than 500 passengers and crews their lives which are owing directly to Boeing blunders and negligence and non vigilance and poor feedback to operators rather than to faulty maintenance or pilot error. And a recent incident involving loose rudder fasteners has raised more concerns with the flying public and only adds to the 737’s most unenviable safety record and inevitable erosion of public trust. When will this flying coffin and death trap on wings finally be put out to pasture for good?

  • Hi
    Thank God there was no loss of life.
    I was a mechanic years ago (DC9, DC10 727,MD80 and 737).
    My two cents, 99.9 of all leaks are around the door seals … It takes some pressure before they pop into position… I am taking a guess this plug had a SEAL that REALLY POPPED!
    Jimmy Q
    P.S. Thanks for all the Great videos and info .. my wife and I watch all the time and she puts up with me yelling at the screen … THAT’S TOO MUCH RUDDER FOR TAKE OFF! IT’S ICE YOU IDIOT! 🙂

    • Update:
      After reviewing “Geoffrey’s” video (Thanks Geoffry)
      It does not appear that the PLUG could remove itself if the SECURING BOLTS were properly installed. The pics do not show any ripping at the Rolling Pin location, only at the hinge

    • Michal (Thattrainandbusguy)


  • Pierre Henriot

    Ty’s comment above is a bit alarming, the conspiracy theory nonsense put aside.
    Certification of a plane should be complete when all tests are successfully passed, not when the set deadline is reached.
    A company can do business in these conditions when it takes the utmost care of delivering the highest quality standards.
    The problem with Boeing seems to be that oversight/inspections were partially delegated to the company itself. I think the 737 Max’s problems are the consequence of this.

    Geoffrey, yes, it seems this wasn’t a plugged door at all, at least not as these doors were constructed before. I guess it saves costs to not be forced to manufacture a different part and not haul it through the cabin for installation. Just put a door in and a panel over it … it also cut costs for door inspections I guess. And now they are looking for the door on the ground.

  • I’m beginning to suspect deliberate sabotage against Boeing. There was an article in Simple Flying recently titled “FAA: No Specific Timetable To Certify Boeing 737 MAX 7”. How can any company run a business under these conditions? It wouldn’t surprise me at all if there were elements within Boeing deliberately trying to derail the company, especially given the current administrations virulent anti-business, anti-American policies….

  • geoffrey nicholson

    I am a bit confused by the description of ‘plugged door’ becoming detached, because the plugged doors on B737s which I flew had dimensions larger than the doorframe. and had to be hauled inboard and twisted before they could be moved outside the doorframe. Similarly with the overwing exit windows.

    In this case has the doorframe become detached from the rest of the fuselage?

    In which case a design fault? Manufacturing fault? Unlikely to be a maintenance fault in such a young aircraft.

    We shall have to wait for a detailed NTSB/FAA report.

    • from what im seeing and reading on comments on forums and other places its a sub contractor issue as they have grounded all 737-max 9’s that had there hulls assembled by the company that did this Alaska 737 max and are checking those door plugs and fixing those that need fixed so i am going to guess the bolts on the door plug were not installed or not installed right

  • Well, yet ANOTHER reason to change the old saying to “If it’s a Boeing (737), I ain’t going.”

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