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Alaska Airlines flight forced to make an emergency landing... 82

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Screenshot_2024-01-07_at_07-01-43_737_Mid-Cabin_Emergency_Exit_Doors_u3fyas.png
Screenshot_2024-01-07_at_07-08-20_737_Mid-Cabin_Emergency_Exit_Doors_vffiyv.png

Comparing theses two photos, did the door leave by itself or did the door and the door frame leave together?

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Ohm's law
Not just a good idea;
It's the LAW!
 
You can see the "stop fittings" or fingers sticking out from the frame, and it all looks reasonably intact and normal. It appears that the plug was able to open normally, by first moving upwards to disengage from the frame, then hinging out from the bottom.
 
more...

"Thousands of passengers face flight cancellations after major US airlines grounded dozens of Boeing jets after a mid-flight blowout over Oregon.

The US aviation regulator said 171 Boeing 737 Max 9s must be grounded for checks after part of an Alaska Airlines plane's fuselage fell off on Friday.

Alaska said flight disruptions are expected to last into next week. United Airlines has grounded 79 planes.
Disruptions are likely to primarily affect flights in the US.

It follows regulator the Federal Aviation Administration (FAA) ordering "immediate inspections" of 737 Max 9s worldwide."


-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
3DD -
re: Yes, some airlines opted to put an emergency exit door, but inoperative, in place. Others went with a plug door. The inop door means they can reconfigure the seating and interior panel without having to recertify the plane. The plug door means they believe they will never recertify or are willing to eat the cost.
Boeing has certified all of the configurations, operable door, inop door, plug door, both structurally and for egress vs number of seats; an airline will not need to "recertify". There probably is not a production option to not install any type of door on the -9. An inop door is heavier than a plug door. So an airline which thinks they will never use the door will opt for a plug door to reduce weight and have a standard window. But when they eventually sell the aircraft the new operator may want to install a operating door if they are in a high dense seating arrangement.

The door came cleanly off, there is no sign at all of any damage to the basic fuselage structure. Which as you said is very strange. This plane has been flying since October. Hard to imagine the retaining fasteners coming loose and falling out to allow the door to slide upwards. Perhaps the fasteners were never installed. Hopefully the NTSB/FAA can figure it out.

Also wonder if there is a difference between the -900 (NG) and -9 (Max) door designs.


 
Love the expression "fell off"

If you want I can get some close up pics of the door retention mechanism on the a220
 
I just realised this, "The impact of this was reduced by two key factors. First of all, the passengers would all have been wearing seatbelts at this stage in the flight, keeping them in their seats."

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
Alistair - I know how operative doors are latched and retained. Just have never seen how the plug "doors" are fastened in. You wouldn't be able to get access to an A220 plug door even if that a/c had one, which I don't think it does, as the interior panels cover it.
 
A relatively new plane... maybe covered by warranty?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
Excellent video. Thanks for posting the link.

Seems likely that the four retaining bolts were somehow not installed at some point in the production process.
 
Only flying since 11/11/23 per multiple reports.

When one this sentence into the German to translate wanted, would one the fact exploit, that the word order and the punctuation already with the German conventions agree.

-- Douglas Hofstadter, Jan 1982
 
It would be the best possible lucky strike imaginable for Boeing if those bolts were left out and neither were there any serious injuries, or no injuries at all, and also that there is minimal damage to the airframe.

Brad Waybright

The more you know, the more you know you don't know.
 
We don't have them.

But I know lads in the heavy maintenance hanger doing the C checks who would get them if we did.

I suspect it will be the same as the emergency exit otherwise it would carry a hefty certification penalty.

 
The door goes down to open, not up.
CORRECTION
The door goes up to open
3ddAVE said:
Chris Brady misspoke. The springs push the door up. The pins are on the door frame and the groove is on the door.
There are springs to hold the door up into the latches.
With the four blocking bolts missing, vibration may have worked the door down until it cleared the latches.
It looks like Boing's MBA driven management still hasn't got their Quality Control together yet.
After rechecking, I agree Dave.


And then there are the airline MBAs who ignored Boing's deteriorating culture and bought the MAX in anticipation of saving a few bucks.
I wonder if their anticipated savings were more than the lost revenue from this grounding.
Gotta love those MBAs.
The lawyers are going to get rich suing Boing for lost revenue.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
I am guessing that the door is about 2000 square inches.
So for every 1 PSIG delta pressure there will be a ton force on the door.
No wonder it came off cleanly.
Has the door been found or did it part company over the ocean?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
It was tracked on primary radar into a Portland neighborhood, but I see no reports of the recovery. There is a river, so that complicates things.
 
Chris Brady misspoke. The springs push the door up. The pins are on the door frame and the groove is on the door.
 
There are videos after the incident. The flight looks fairly full. It seems odd that nobody was seated by the door. Perhaps there was a warning sign and the people were moved? It seems like it was fairly violent when it failed. The pictures posted here show the upholstery and padding were sucked off of a seat frame.
 
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