A Matter of Millimeters: The story of Qantas flight 32

[jemhouston]

https://admiralcloudberg.medium.com/a-m ... aa62dc98e7





Link only, you need to see pictures

[Kunkmiester]

My eyes started bugging out when he went into the design and machining details. So many failures. I've typoed offsets before, moving things .020 instead of .002, it sounds like that happened on a print-the 0.05 to .5 sounds like a typo that was missed. Someone probably several someones) should have noticed that shouldn't be that loose.

Then the machining setup, yeesh. You don't set things up where things can move that much, or reprobe. The timing pin thing was nuts, that should have been machined complete to start with and probed on the bore.

It sounds like that facility really needed to be flipped over.

[Pdf27]

I've got shouty about far less serious levels of complacency than shown by Hucknall there. Checking against the manufacturing layouts rather than the design drawings is particularly egregious. Airbus comes out pretty well though.

[warshipadmin]

The engineer that produced the coverup statistical analysis should be hung out to dry, as well as whoever modified the offset to 0.50 mm, and the checker that failed to see it.