>But the big money comes from the parts suppliers. There facilities and manufacturing processes have to be approved. When they are they quite often are the only source for certain parts.

Partially. The biggest problem is in the last few decades companies have been buying each other up, it's so bad now that I believe Rockwell owns 70% of all parts companies for aviation. Basically, one giant monopoly. Even Boeing has shit its pants and is starting to slowly inhouse some manufacturing again.