Go Back  PPRuNe Forums > Flight Deck Forums > Accidents and Close Calls
Reload this Page >

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

Accidents and Close Calls Discussion on accidents, close calls, and other unplanned aviation events, so we can learn from them, and be better pilots ourselves.

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

Old 6th Jan 2024, 17:49
  #121 (permalink)  
 
Join Date: Apr 2015
Location: Under the radar, over the rainbow
Posts: 794
Received 0 Likes on 0 Posts
Originally Posted by Maninthebar
This implies to me that a specific issue has been identified as THE cause of this event.

Which, without the door present is remarkable and points to some gross failure of assembly
171 airplanes of the 218 total delivered are covered by the EAD. The ones not covered are the comparative few that have been in service long enough to have already been subject to an inspection including the door plug.

I other words, you're probably right.
OldnGrounded is offline  
Old 6th Jan 2024, 18:01
  #122 (permalink)  
 
Join Date: Dec 2014
Location: Somerset
Posts: 40
Received 0 Likes on 0 Posts
Likely Cause

Originally Posted by Maninthebar
This implies to me that a specific issue has been identified as THE cause of this event.

Which, without the door present is remarkable and points to some gross failure of assembly
I’d like to bet that someone in engineering at Boeing will have looked at the photos and already worked out exactly what happened.
Europa01 is offline  
Old 6th Jan 2024, 18:19
  #123 (permalink)  
 
Join Date: Apr 2018
Location: Sudbury, Suffolk
Posts: 264
Received 4 Likes on 1 Post
Yup

So not a failure of design (would be all in series with no inpection)

Not a fatigue failure (would require much greater diagnosis)

Points to failure of assembly e.g. missing bolts or other fixings that are on the design
Maninthebar is offline  
Old 6th Jan 2024, 18:20
  #124 (permalink)  
 
Join Date: Apr 2004
Location: london
Posts: 69
Likes: 0
Received 0 Likes on 0 Posts
The Boeing MAX "jump seat"


freshgasflow is offline  
Old 6th Jan 2024, 18:27
  #125 (permalink)  
 
Join Date: Sep 2022
Location: EGBO
Posts: 60
Received 30 Likes on 14 Posts
Judging by where the altitude drops on the FR24 track, the door may well be here somewhere.
It's a well populated area, so I'd have thought someone will eventually find it...


VM325 is offline  
Old 6th Jan 2024, 18:31
  #126 (permalink)  
 
Join Date: Jan 2008
Location: Netherlands
Age: 46
Posts: 368
Likes: 0
Received 3 Likes on 3 Posts
Originally Posted by OldnGrounded
171 airplanes of the 218 total delivered are covered by the EAD. The ones not covered are the comparative few that have been in service long enough to have already been subject to an inspection including the door plug.

I other words, you're probably right.
Or they have the high density config with a real door installed?

Non max 737-900 also seem have these plugs.Why are these not affected?
procede is offline  
Old 6th Jan 2024, 18:46
  #127 (permalink)  
 
Join Date: Jan 2023
Location: Puget Sound, WA
Posts: 186
Received 4 Likes on 2 Posts
Meanwhile, if you're looking for a completely deranged hot take completely divorced from fact, here you go:

https://www.thedailybeast.com/boeing...rlines-blowout
remi is offline  
Old 6th Jan 2024, 18:50
  #128 (permalink)  
 
Join Date: Jan 2023
Location: Puget Sound, WA
Posts: 186
Received 4 Likes on 2 Posts
Originally Posted by VM325
Judging by where the altitude drops on the FR24 track, the door may well be here somewhere.
It's a well populated area, so I'd have thought someone will eventually find it...
A metal door sized object at 12,000 feet should have left clear primary radar returns. It shouldn't be too difficult to find in the "tapes," if someone hasn't already found the door lying on top of Rudolph in their front yard.
remi is offline  
Old 6th Jan 2024, 19:08
  #129 (permalink)  
 
Join Date: Sep 2013
Location: Manchester, NH
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by MechEngr
The plug will be an exit door with an internal panel to cover access to the release mechanism so no rivets or hiloks. In that case I'd guess the exit door wasn't properly latched before the interior panel was installed. Queue up an inspection of all such installations.
Assuming the exit door is the cause, who would have configured the door to be properly latched and secured prior to the installation of the panel, Alaska or Boeing?
ReggieMoto is offline  
Old 6th Jan 2024, 19:08
  #130 (permalink)  
 
Join Date: Oct 2019
Location: USA
Posts: 911
Received 275 Likes on 150 Posts
Informative video:

Indicates a non-functional door was used rather than in-oping an exit door and suggest retaining bolts were missing. If so, then there will be a paper trail back to whoever signed off that the bolts were installed.
MechEngr is offline  
Old 6th Jan 2024, 19:09
  #131 (permalink)  
 
Join Date: Jan 2015
Location: Usually firmly on the ground
Posts: 150
Likes: 0
Received 4 Likes on 3 Posts
Originally Posted by runner1021
All things considered, Boeing had a very lucky day. Had this happened on a flight halfway to PHNL at FL390, Boeing would no longer be in the commercial aircraft business.
I think I see what you did there.
Eutychus is offline  
Old 6th Jan 2024, 19:24
  #132 (permalink)  
 
Join Date: Jan 2008
Location: Netherlands
Age: 46
Posts: 368
Likes: 0
Received 3 Likes on 3 Posts
Originally Posted by MechEngr
Indicates a non-functional door was used rather than in-oping an exit door and suggest retaining bolts were missing. If so, then there will be a paper trail back to whoever signed off that the bolts were installed.
If this true, then there is a very serious quality control issue extending much further than just these plugs.
procede is offline  
Old 6th Jan 2024, 19:28
  #133 (permalink)  
 
Join Date: Nov 2010
Location: Canada
Posts: 133
Likes: 0
Received 0 Likes on 0 Posts
ETOPS

That it was removed from ETOPS schedules with the prior pressurization issues shows that the system at least filled some of the Swiss cheese holes.

if it was anywhere at FL39 instead of 16,000 feet the decompression would have been much more dramatic - probably sucking that kid out the hole that lost only his shirt. Lots of ‘lucky’ elements to this.

The fact that the FAA did a mass grounding points to it being a factory install issue - not an Alaska maintenance issue - such as troubleshooting the pressurization snag.
MLHeliwrench is offline  
Old 6th Jan 2024, 19:28
  #134 (permalink)  
 
Join Date: Jul 2016
Location: Broughton, UK
Posts: 183
Likes: 0
Received 5 Likes on 3 Posts
Force on Door

Just to put some figures on the forces involved. If the door is 4ft by 3ft, then its area is 4x3x144, = 1728 square inches.
If the differential pressure is 5 psi, then the total force on the door is 8640 pounds, or about 4 tons.
As the door would weigh much less than 1/4 ton, it would experience an acceleration of over 16G., if all the fasteners failed at once.
scifi is offline  
Old 6th Jan 2024, 19:40
  #135 (permalink)  
 
Join Date: Feb 2004
Location: Dublin, Ireland
Posts: 505
Received 8 Likes on 6 Posts
There's what looks like quite an informative contribution by a former Boeing engineering guy (jimpalmer1969) in the comments section below Juan Browne's initial analysis.
Liffy 1M is offline  
Old 6th Jan 2024, 19:46
  #136 (permalink)  
 
Join Date: Jun 2009
Location: Montreal
Age: 65
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
The emergency airworthiness directive has been issued, just now

https://drs.faa.gov/browse/excelExte...106201913.0001
incompleteness is offline  
Old 6th Jan 2024, 19:52
  #137 (permalink)  
 
Join Date: Oct 2013
Location: OAK/SFO
Age: 79
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Misread what you wrote as "Boeing has sent a team of 20 accountants" which would make sense for the company, post Stonecipher.
Plane Watcher is offline  
Old 6th Jan 2024, 19:59
  #138 (permalink)  
 
Join Date: Nov 2010
Location: Canada
Posts: 133
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by incompleteness
The emergency airworthiness directive has been issued, just now

https://drs.faa.gov/browse/excelExte...106201913.0001

FAA emergency AD grounds all MAX 9 with dummy plug door installed. Those airframes with operational emergency exit at that cabin location are not affected by AD.

The AD basically says no further flight until a yet to be specified inspection is carried out.

id imagine this inspection will be released very shortly.
MLHeliwrench is offline  
Old 6th Jan 2024, 19:59
  #139 (permalink)  
 
Join Date: Jan 2008
Location: Reading, UK
Posts: 15,899
Received 252 Likes on 119 Posts
Originally Posted by incompleteness
The emergency airworthiness directive has been issued, just now

https://drs.faa.gov/browse/excelExte...106201913.0001
Though unhelpfully it doesn't contain any details of the required inspection/rectification action.
DaveReidUK is offline  
Old 6th Jan 2024, 20:05
  #140 (permalink)  
 
Join Date: Jun 2009
Location: Montreal
Age: 65
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by DaveReidUK
Though unhelpfully it doesn't contain any details of the required inspection/rectification action.
I feel like that's because they don't know the exact root cause. They give a contact person in para j, I imagine he and his people will be up for a few days looking at all the feedback from inspections and coordinating with Boeing. Then there will be a final AD.
incompleteness is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.