dixi188
Yes you are correct, but my understanding is that the CMM has all the various procedures just like an aircraft AMM has, but the issue was what of the hundreds of items within it that you need to perform to meet the requirement of a restoration.
The other issue is that the restoration as per the MRBR/MPD is for both LDG and components.
So what components have to be included within the requirement, it was a mess and the other issue was what parts would be scrapped as part of the restoration.
Anyone who has knowledge of how the MRBR is developed knows that airlines continuously supply details of findings from inspections, this enables increase in inspection intervals and the odd time a reduction is needed.
Corrosion findings will some times stop a structural inspection interval being increased, but this is where LDG becomes an issue.
Most airlines tend to swap out LDGs when they go for overhaul, they can't wait for the months it takes to send away for restoration and be returned.
So they fit a replacement from another source.
The issue is that very few airlines bother to get a full shop visit report, this from the LDG that they have swapped out for a serviceable one.
This LDG may have had a number of sections/parts that would have had corrosion and at what level.
This would be removed and repaired, or it could just be replaced, this is because it would be cheaper to replace and not repair.
This means the likes of Boeing and Airbus don't get the information that they need.
As you can see LDGs have always been a problem and that is why in my opinion you are going to continue to see this type of accident on aircraft in the future.