Originally Posted by
SLFinAZ
To the best of my admitted limited knowledge this is the 1st incident I can recall where a single plane had significant issues across multiple consecutive flights and remained in service and suffered a catastrophic event. So it's really an economic and cultural issue, possibly specific to Lion Air or potentially more wide spread. I realize that planes are routinely dispatched with degraded capabilities but from what I have read here it would seem that many of those who work in the pointy end have expressed dismay (or am I wrong) that the plane was cleared given the nature of the ongoing issues. Once the problem persisted in spite of the swap out how could you "sign off" for a revenue flight?
Assuming the problem was "intermittent", troubleshooting becomes very, very difficult and the Maintenance Manual/Fault Isolation Manual are not always a lot of help. Anyone who's a backyard mechanic can appreciate how frustrating it can be to find a problem that only occurs when you're driving 60 miles per hour - but not every time you drive 60 miles per hour.
I became a big hero to a particular operator many years ago when, after looking at some DFDR data, I figured out that their recurrent FADEC problem they'd be trying to solve for a month was occurring when the leading edge devices were retracted. I told them to go look at the wire bundles in the vicinity of the leading edge actuators and they found the chaffed bundle problem the next day.
I wouldn't be too quick to condemn maintenance because they struggled to correct an intermittent fault.