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Comment by lefixx | Hacker News Reader

4 bolts (I actually think they are screws) is not a danger but it signals a failure in the maintenance pipeline.

> it signals a failure in the maintenance pipeline.

Without knowing the risk caused by it, it may signal nothing of the sort. The mechanics already had cleared the plane to fly. Very, very few planes have any sort of in-flight issue like that. Those facts, rather than our ignorant speculation, signal the state of the 'maintenance pipeline' (if such a thing exists).

Unless they were inspected, acknowledged "not dangerous" and scheduled for replacement some time later. There are whole lists of things that are not required to be in good working order for the plane to fly safely, see e. g. what MEL is.

it might not even need to be noted and scheduled.

It may be the case that some failures are expected and tolerated between periodic inspections, and the period is designed to catch anything before it gets too far.

But why not have more buffer in their supply chain so that when someone notices missing bolts, or bolts need to be replaced, they have them?

There are clearly deep quality problems that have gone on beyond the door plug. Something is just off in the culture that it's completely normal to just have a lot of bolts missing, because it's within tolerance. If bolts come loose in non-visible places, that's what inspections are for.

The culture is apparently "eh there's missing bolts and it's too big of a pain to schedule and order them" for something that, in this plane's case, took minutes to fix.

That's a symptom of a very broken culture

Where is this bit about the supply chain and missing bolts coming from, or the part where someone knew they were missing and ignored it? Was that in a different article?

I guess my main point is that it is very difficult for outside amateurs to judge quality culture. They dont know the risks, severities, and existing controls. Therefore they dont know if something is completely typical and acceptable, or outrageous.

4 screws randomly distributed among the 109 might not be a danger, but these were 4 in a row, which seems like it would be more hazardous.

You ever seen what happens when a screw comes loose and hits another surface at 500 mph?

I have had a small screw go through a plane propeller before. 1 missing screw, let alone 4, would terrify me.

I’ve noticed missing bolts a few times when sitting in wing view seats. Didn’t realize that isn't supposed to be ok. This problem might be quite common.

Missing screws CAN be ok. The issue is where the screws went, and why they came out.

I was about to say this, I'm not 100% sure but I think I did see that as well

> You ever seen what happens when a screw comes loose and hits another surface at 500 mph

well, obviously you are screwed.

edit: to be more constructive "Felipe Massa's life-threatening crash "( https://www.youtube.com/watch?v=wEt5pbyiIdM )

If a screw coming loose and hitting another surface is a concern, shouldn't the missing fasteners in fact enhance safety? They're the only ones we can be sure won't fuck up the engine or whatever.

Unless one flies out at 750mph, hits a critical part of the plane somewhere else.

Has that ever happened?

If your Airbus flight goes 750mph you have other problems

What is terminal velocity for a commercial airliner?

An American or a European airliner?

750mph ground speed flying in a jet stream

ground speed doesn't matter. if something comes off the aircraft it'll be in the same relative air current

Air speed doesn't matter either, since the plane is traveling at the same speed before and after separation of the bolt.

good point, god forbid you get somewhere on time in an Airbus

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