Alaska Airlines 737-900 MAX loses a door in-flight out of PDX

[Tailspin Turtle]

I question whether Spirit installed the accident plug/door. That would require that Boeing knew the configuration of the cabin that this particular fuselage would be utilized for. It seems more likely that Spirit completed it to some uniform standard and when it got to Boeing, it was modified to meet the buyer's requirement.

[DaveReidUK]

Originally Posted by roger4

The photos on the first page of this thread show both left and right rollers in place in the frame, exactly where they should be.

It is indeed, scrub that theory.

[roger4]

Originally Posted by Tailspin Turtle

I question whether Spirit installed the accident plug/door. That would require that Boeing knew the configuration of the cabin that this particular fuselage would be utilized for. It seems more likely that Spirit completed it to some uniform standard and when it got to Boeing, it was modified to meet the buyer's requirement.

On-line images of the fuselages on the trains during shipment from Wichita to Seattle show all the doors are in place, so I think Spirit do indeed fit them. It is indeed the case that Boeing know well in advance which line number airframe will go to which customer, and hence the required spec for Spirit to build.

[tsumini]

Originally Posted by EXDAC

Yes, it does seem to be present although partially obscured by insulation.

Dimension between fore and aft roller pins would be interesting. If too wide may be indicative of roller pins disengaged even with lock bolts present. Should be a controlled dimension.

[DaveReidUK]

Originally Posted by Tailspin Turtle

I question whether Spirit installed the accident plug/door. That would require that Boeing knew the configuration of the cabin that this particular fuselage would be utilized for. It seems more likely that Spirit completed it to some uniform standard and when it got to Boeing, it was modified to meet the buyer's requirement.

Here's a -900ER fuselage in transit from Spirit to Boeing, with the door plug already fitted:



Note also that it's marked with the Boeing Line Number (7562), which ties it to the intended customer, in this case Delta. I doubt the SOP for the 737-9 is any different.

[SRMman]

The Other Door!

"Flight attendant says the cockpit door blew open in the decompression. It hit and damaged the lavatory door, jamming it closed. No one was inside. Flight crew was also interviewed."

Is this another concern? Clearly not ideal that the door should open in an uncontrolled way, and then cause related damage. I've no idea what the certification requirements are for the cockpit door, but it seems very odd that this one 'blew open', and not even at maximum pressure differential. Surprising that it doesn't apparently have any pressure relief system for this eventuality.

[ATC Watcher]

Originally Posted by SRMman

The Other Door!

"Flight attendant says the cockpit door blew open in the decompression. It hit and damaged the lavatory door, jamming it closed. No one was inside. Flight crew was also interviewed."

Is this another concern? Clearly not ideal that the door should open in an uncontrolled way, and then cause related damage. I've no idea what the certification requirements are for the cockpit door, but it seems very odd that this one 'blew open', and not even at maximum pressure differential. Surprising that it doesn't apparently have any pressure relief system for this eventuality.

I wondered that as well when I read that , but it just could be that the door was briefly unlocked , like after someone just came out or just in . would explain the damage to the lav door if it was "free" . But that will be cleared up fast I believe.

[thnarg]

Originally Posted by ATC Watcher

I wondered that as well when I read that , but it just could be that the door was briefly unlocked , like after someone just came out or just in . would explain the damage to the lav door if it was "free" . But that will be cleared up fast I believe.

Flight deck doors have panels designed to “blow open” if the cabin depressurises to avoid damage to the surrounding structure.

[A0283]

Originally Posted by Tailspin Turtle

I question whether Spirit installed the accident plug/door. That would require that Boeing knew the configuration of the cabin that this particular fuselage would be utilized for. It seems more likely that Spirit completed it to some uniform standard and when it got to Boeing, it was modified to meet the buyer's requirement.

Unlikely. The plug is an OPTION, not a MODIFICATION, and so you know it in advance.

How much in advance depends on a lot of things, on how Boeing organises that (in how and when in the integral proces they make the plane type and customer specific).

If a manufacturing error or failure might turn out to be causal or contributory, there might have been a hick-up starting in that process.

The configuration of a cabin can be viewed in a similar manner, but keep in mind the cabin arrangement itself is flexible. So cabin configuration is not per se fixed.

[ATC Watcher]

Originally Posted by thnarg

Flight deck doors have panels designed to “blow open” if the cabin depressurises to avoid damage to the surrounding structure.

Thanks .I learned something . That clears it up then .

[SRMman]

To me it would be a strange coincidence that this "very important that it's kept closed" door happened to be open just at the time of the depressurisation...

[M4rtyman]

I'm no behavioural scientist, or expert at reading body language. However, after watching and hearing Ms Homendy's comments on the lack of Cockpit Voice Recording, I think it would be fair to say that she is a wee bit pi**ed off, sorry ... "frustrated" ... with the FAA. I get the feeling she would have loved to have gone on a full blown rant.

[A0283]

Originally Posted by ATC Watcher

Thanks .I learned something . That clears it up then .

Not there yet;-) … a blow-out panel in the cockpit door operating as intended … is quite different from the cockpit door itself being blown open so hard it jammed the lavatory door … the NTSB press conference Nr 2 was about the door is my impression… interesting question for chair Homendy … again words are important

[RUTUS]

Originally Posted by Tailspin Turtle

I question whether Spirit installed the accident plug/door. That would require that Boeing knew the configuration of the cabin that this particular fuselage would be utilized for. It seems more likely that Spirit completed it to some uniform standard and when it got to Boeing, it was modified to meet the buyer's requirement.

I read somewhere that Spirit installs the plugs in a provisional manner but that they are then removed by Boeing because they need access when they complete the aircraft. It seems very likely that Boeing would at least open them as normally there is a door there and their procedures would be based on that.

If the bolts are missing or incorrectly installed Boeing would be responsible.

I haven't been able to verify the information but those interested in the blame game probably should try before absolving Boeing.

[EDLB]

https://www.bbc.co.uk/news/world-us-canada-67911193

The door/plug and two phones have been found. One in working condition still in airplane mode. So they can reassemble the plane and get it in airworthy condition.

[DaveReidUK]

Originally Posted by thnarg

Flight deck doors have panels designed to “blow open” if the cabin depressurises to avoid damage to the surrounding structure.

Are we, perhaps, seeing the difference between a cabin depressurisation following, say, a window blowing out, and the effect of a hole suddenly appearing that's many times the size of a window?

The end result will be the same - a cabin at ambient pressure - but the time taken to get to that point will almost certainly vary. What rate of decompression are cockpit door blowout panels intended to cope with?

[Reverse rotation]

Surely the doors / plugs need to be opened or removed when the fuselage gets painted?

[slip and turn]

The state of the right hand side plug liner - obviously interfered with - by NTSB? ?

Originally Posted by ImbracableCrunk

NTSB B-Roll - Alaska Airlines Flight 1282 Boeing 737-9 MAX

https://youtu.be/QoiGuuGZPNc?si=YEUrKSRCY8nQPNPw&t=132

Check out 2:12 - the right side is being examined and light is coming through. Either the NTSB opened the right side for inspection, or the right side was also not secured.

How did the front edge of the liner get into that crooked state?

Anyone else pick up on 1a sound asleep's interesting post earlier today?:

Coincidence? Or ...

S&T

[Obba]

Heard on the news that the door has been found in someone's back garden.
Not much more than a headline from the Telegraph...


Door plug from Alaska Airlines plane found in teacher’s garden may be prove crucial in investigation (telegraph.co.uk)

[DaveReidUK]

FAA approves (but doesn't yet make public) means of AD compliance

The FAA has approved a method to comply with the FAA's Boeing 737-9 emergency airworthiness directive, and it has been provided to the affected operators. The FAA’s priority is always keeping Americans safe. In that spirit, Boeing 737-9 aircraft will remain grounded until operators complete enhanced inspections which include both left and right cabin door exit plugs, door components, and fasteners. Operators must also complete corrective action requirements based on findings from the inspections prior to bringing any aircraft back into service.

Updates on Grounding of Boeing 737 MAX 9 Aircraft