The Boeing Issue Isn’t About Bolts
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https://youtu.be/UKR79e7BKcY
https://www.faa.gov/sites/faa.gov/files/about/initiatives/maintenance_hf/training_tools/FFP%2520Buck%2520Stops%2520with%2520Me%2520HTML.zip
Interesting read from the FAA for anyone with spare time. Tales of FFP (Failure to Follow Procedure)
I'm starting wonder if the proximate cause was 4 missing bolts (2 in the tracks and 2 through the spring guides). This allowed to door to move upward and depart. The caveat is someone, based on a misunderstanding, overtightened the stop pins to arrest the movement of the door and keep it fixed...
New speculation, Boeing accidentally switched the door with another Spirit fuselage's door. The mismatched micro adjustments went unnoticed. This presumes Spirit was responsible for the adjustments.
Is this senior plausible? *
1. Exit is open and ready to be closed.
2. Plug was pushed down against the springs and the top tracks and roller pins seated.
3. Two upper cross locking bolts are forgotten but the spring does not push the plug upward and out of the tracks because the stop pads are...
Quoting waross
waross, how do you feel about these comments?
Those springs on the hinges are to hold the door up when it is open or about to be opened.
If the door slid downwards when it was open, then it wouldn't close.
The stop pins would impact in front of the stop pads instead of behind...
Stop pads
Thank you for the clarification. Very much appreciated. It seems the inflight pressure on the pads would keep the door plug in place unless the plug was partly open before pressurization.
https://www.reuters.com/business/aerospace-defense/spirit-aero-made-blowout-part-boeing-has-key-role-sources-2024-01-07/
Quality control is more difficult when more than one factory floor is involved. (Not clear if MAX 9 is shipped by rail.)
Loose bolt talk
You are mostly correct Murph. No bolts keep the plug closed. The pads do not keep the plug closed, they act in the other direction and absorb negative pressure and minor distortion. The plug is held in place by the interference with the frame when in the lower position or...
View of hinges. Due to minimal damage, it seems the door simply transitioned upwards and then opened.
https://www.flickr.com/photos/ntsb/53450362798/in/album-72177720313904488/
Loose bolt visible:
https://www.youtube.com/shorts/K6hephOelG0?feature=share
The way the large doors have to move inside first before the door opens has always made me confident. A plug of this size that depends on just bolts may not be as failsafe.
Why did this plug popout? Who at Boeing is feeling queasy right...
OceanGate had modest intentions with Cyclops 1. Then with Titan (Cyclops II) the CEO extended ambitions by simply scaling up. It seems tourist visits to the Titanic was tacked on. In the end, the project was over-extended. Parts of the process were done in reverse. Mission creep failure...