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I was with you until midway. You're making quite an assumption while the NTSB's investigation is still ongoing. We don't know the root cause - Those bolts may h

I was with you until midway. You're making quite an assumption while the NTSB's investigation is still ongoing. We don't know the root cause - Those bolts may have very well been in place and passed an inspection during install, but rattled loose and fell out (and then subsequently were blown out of the plane when the plug failed.) United reported loose bolts, not missing bolts. This indicates a more systemic issue and not just a miss by an Alaska Airlines maintenance worker taking a phone call. If the systems involved in the failure are all "Boeing", it doesn't seem unreasonable to consider changes, such as requiring a 3rd party with no self-interest in rubber-stamping the go-ahead, to inspect the work.

graton 3y ago
> Those bolts may have very well been in place and passed an inspection during install, but rattled loose and fell out (and then subsequently were blown out of the plane when the plug failed.) The bolts the NTSB can't find are not the ones that have been found to be loose. The bolts they can't find are the ones with the castellated nuts and cotter pin. Very hard to imagine those vibrating loose. And for the door to transit in an upward direction it would really require all four of those to fail or for them to not exist. https://www.youtube.com/watch?v=maLBGFYl9_o https://www.youtube.com/watch?v=maLBGFYl9_o at around the 7:26 mark has a great explanation of how the door is secured and it seems like as long as there is at least one of the four bolts installed the door can't move.
- 51Cards 3y ago
  Agreed, those are not going to rattle loose. Even if the cotter pins were all missing, 4 nuts would have had to back off fully and 4 bolts would have had to wiggle out, not to mention they would likely be under pressure from the guide pin during flight. Again, the final report will tell all but it really seems to me that they were just not there.
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strangattractor 3y ago
I do not think using words such as "likely" and "I suspect" constitute asserting anything. Those doors and plugs are designed to wedge themselves against the seal when they are in place. Just looking at them from the outside will not give any indication as to whether they are bolted. A few rapid vertical jolts (which might occur in flight) could jar them loose without the bolts. There is no damage to the structure of the plane. Bolts on planes are either carter pinned, safety wired or have a nylon ring to prevent loosening. They generally don't just fall off - not to mention having several fall off simultaneously.

graton 3y ago

> Those bolts may have very well been in place and passed an inspection during install, but rattled loose and fell out (and then subsequently were blown out of the plane when the plug failed.) The bolts the NTSB can't find are not the ones that have been found to be loose. The bolts they can't find are the ones with the castellated nuts and cotter pin. Very hard to imagine those vibrating loose. And for the door to transit in an upward direction it would really require all four of those to fail or for them to not exist. https://www.youtube.com/watch?v=maLBGFYl9_o https://www.youtube.com/watch?v=maLBGFYl9_o at around the 7:26 mark has a great explanation of how the door is secured and it seems like as long as there is at least one of the four bolts installed the door can't move.

51Cards 3y ago
Agreed, those are not going to rattle loose. Even if the cotter pins were all missing, 4 nuts would have had to back off fully and 4 bolts would have had to wiggle out, not to mention they would likely be under pressure from the guide pin during flight. Again, the final report will tell all but it really seems to me that they were just not there.

deleted 3y ago

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strangattractor 3y ago

I do not think using words such as "likely" and "I suspect" constitute asserting anything. Those doors and plugs are designed to wedge themselves against the seal when they are in place. Just looking at them from the outside will not give any indication as to whether they are bolted. A few rapid vertical jolts (which might occur in flight) could jar them loose without the bolts. There is no damage to the structure of the plane. Bolts on planes are either carter pinned, safety wired or have a nylon ring to prevent loosening. They generally don't just fall off - not to mention having several fall off simultaneously.