So...seeing how I work in Delta's TechOps division, I feel that I need to add to this because at least one of the instances referenced in the article is an embellishment for the sole purpose of making a point.
I can speak to the Boeing wide body fleet. Yes...our heavy maintenance packages are worked in the Pacific by three different companies. Their work and attention to detail is amazing, and it's reflected in the quality of work. We have never had an issue with incorrect work or overruns of any kind...contrary to American which, for a while, was making the news for those very reasons all too often. The airline having the work done is just as responsible for the oversight as the group doing the work. Delta has full time inspectors and managers onsite at all our locations.
It may sound like we are shipping work off shore; however, when you factor in the size of our fleet and how many aircraft have to be in work at any given time there is not enough real estate to put the aircraft. In an odd twist, by outsourcing our heavy visits it frees up valuable hangar space where we do light checks and more contract work than you can shake a stick at. By doing this we protected jobs and actually grew the mechanic ranks by a good bit. I know it sounds odd, but today in our hangar there are no less than 6 aircraft that are customer's jets. Add this to all the engine maintenance contracts and component maintenance contracts, and we're talking about a lot of jobs added rather than lost.
Now, that embellished story on the China Airlines 737...
It did not burn up due to a mechanic's shortcoming. There was an assumption that a washer could have been omitted due to difficulty in installing it; however, that was never proven. There was an inspection driven by the fire and there were several 737's in the worldwide fleet that had loose nuts that had not come loose. A fix was implemented that did torque checks on the affected bolts and installed downstops on the flaps to keep them from extending beyond a point that could cause another leak. China Airlines was just the unfortunate carrier that had the first issue as a result.