When you get on a plane, you would prefer that it not catch fire in mid-air, right? You would feel better knowing that someone had checked out the plane's designs to make sure that it wouldn't spontaneously combust, yes? And you would hope that the person doing the checking was not working for the plane's manufacturer, yeah?
Well, that's not what happened with the Boeing 787 "Dreamliner." Instead, as reported in The Wall Street Journal:
"Only about two dozen FAA officials were assigned to oversee certification of the 787. FAA manager Steve Boyd told the NTSB last month that the team started with scant knowledge of the plane's advanced battery technology. Then it allowed FAA-designated industry experts from Boeing and its suppliers to run all tests and conduct final safety reviews 'with confidence that they [would] make the right call,' he said."
There's a reason for this. Modern airplanes are unbelievably complicated, and the FAA has nowhere enough staff with the necessary expertise in the latest technologies. That leaves the FAA with little choice but to depend on Boeing employees and contractors to review and test the systems they designed and built themselves.