9 Comments
author

Great explainer.

(And I'll be keeping that seatbelt on for the entire flight moving forward!)

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author

I spent 17 minutes on the video. Seems ridiculously hard to make the door fail in the way it did (clean) with the locking bolts in place. Unless 4 bolts sheared that is. I am no structural or metallurgical engineer to know what that would take on a brand-freaking-new aircraft. But an emergency AD might be the tip of the iceberg in the supply chain.

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author

I wonder if one bolt failed and the force might have then been enough to shear the rest. That’s just speculation.

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author

I’m speculating it wouldn’t have been such a clean separation if just one bolt sheared pulling the others out--the door would have flailed and damaged the fuselage wouldn’t it? I hate to guess, but maybe the nuts weren’t even wired in or the bolts were removed and not reinstalled.

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Jan 10Liked by David Thornton

More likely.

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Jan 10Liked by David Thornton

Not likely.

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Jan 10Liked by David Thornton, Jay Berman

Thanks for the details. Aircraft structural design exceeds my knowledge and experience. It is cutting edge. There's not much room for assembly and fabrication errors. I saw a comment somewhere that it was the Republican's fault for reducing regulations. I really can't really see federal inspectors double checking riveting and torguing and securing bolts under any administration. This incident was almost certainly a human performance and quality control error. I've seen piping systems fall off concrete walls because of failure to check fastener torgue and tension.

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author

I don’t think politics had anything to do with it. Aviation companies do a surprising amount of inspections and testing themselves. Companies employ licensed inspectors to sign off on inspection to FAA standards. When things aren’t up to code, if the company finds out about it, they often self-report to the FAA. They may still be sanctioned and fined but not to the extent that they would if they tried to cover it up.

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I don't either. I intended it to be just a passing mention of what I thought was a dumb-ass comment - especially since the executive branch has been democrat controlled for three years. The implication being that we can't have half the work force being federal inspectors no matter who is in charge.

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