Originally Posted by
DaveReidUK
To be fair to Boeing, they could be forgiven for not foreseeing that anybody would think sticking a pin through the middle of a hollow pivot bolt (if indeed that's what happened) was going to stop anything moving ...
I’m not so sure. That task is repeated regularly around the World 24/7/365; if it is possible to do it wrong, it will happen. That’s the point of good mechanical design: to make it very hard to have parts in the wrong configuration.
Thinking about it, we don’t know how many times the pin has been put in the wrong hole as you wouldn’t find out about it unless a) you ran a systems test that actually would retract the gear on the ground without a pin or b) the person who removed it noticed that it wasn’t right. The setup has to be foolproof enough that a short person who is not that familiar with the type can reach in on a dark night and put the pin in the right place, and I don’t think the current arrangement passes this test, hence the AD...