I built qa software to digitize the forms and signature process like what’s mentioned in the article as having not correctly been signed off on.
I ate lunch with repair engineers that had dark wells of knowledge about the engines they worked on. They could talk so deep on a subject that lunch break was over and we’d resume conversation over weeks.
There’s a paragraph in this post that hits a few points that are very subtle. The missing sign offs and engineers not knowing the process and and and. I think the criticism of RR is valid here. The qa manager at the mro I worked at was a force of nature. He was feared and uncompromising. He was also the signature that could cause an engine shutdown in flight. I admired this person and still do.
There’s small issues like this that go on every day on every engine model all over the world. There’s thousands of engines flying right now that have little defects that could cause a shutdown. There’s issues that have been identified, signed off as low risk and will be checked next time the engine comes in for overhaul.
There’s engineers out there that see the same fault, a premature cracked pipe, carbon buildup, abnormal corrosion, after a while of seeing this problem, they’ll raise the paperwork which will go up the chain and sit. It may be ignored, taken for information for future designs, identified as something that should be fixed or monitored or the frequency of monitoring increased. Maybe the part life will be reduced or you will be forced to NDT the part at each overhaul.
The cheese wheel concept is great as these systems are so complex there’s always going to be some issues.
As for Qantas, near the end it mentions the plane was repaired at great cost. It’s a source of company pride that they’ve never lost an airframe. They repair planes which are BER (beyond economic repair) just to keep this record.