A recent article on the QF A380 incident highlighted a significant error caused by the FAI being undertaken against the manufacturing data rather than the original (digital) design data. I have come across this a few times and must admit that I probably have not paid enough attention to the original design data when reviewing the FAIR. In the incident, the FAIR was correct against the manufacturing data but the manufacturing engineers had made an error in the transfer from the design data. Does that mean that all FAI should only be against original design data? What if the manufacturer only receives digital design data, should auditors be checking that the transformation to manufacturing data ensures the design characteristic results? Should FAI only be against original design data? (somewhat rhetorical these) Any thoughts??