Wrote a thoroughly boring paper for a supply chain management course on essentially this very subject. The operation in question was a small composites shop manufacturing generally small aircraft panels.
Their longer-term goal is to get into becoming a key supplier for major aircraft OEMs.
We initially found their waste to be rather high. We then found that their rejected parts rate was high. Working backward through the process, we discovered that their clean room processes weren't particularly well controlled, nor were their quality functions managed. We then found that their sourcing for such items as prepreg and honeycomb was large, infrequent lots (this is bad because these items have a shelf life, even when properly stored) resulting in either waste or usage of expired materials.
There were other issues, but in short, they would be unable to become a key supplier for a ISO 9001 customer (which most major aerospace manufacturers are... though having read this thread I begin to wonder if Agusta is) without changing basically every aspect of their supply chain, from procurement through quality.
As I read blakmax's posts, I get the sense that there is a lot of variability in the quality of production in these parts, to include voiding, moisture, improper curing, and whatever other problems can arise in the process. I would think any of these would make the final product unstable with regard to widely varying environmental conditions.
So, yes, blakmax... I think quality may be the thing to be attacked. I've learned a great deal reading your posts. Thanks for that.