Originally Posted by
rugmuncher
Non-destructive testing of composite structures has come a long way since "tap-testing" using the rounded edge of a coin, although, it is still one of the main methods in most spec's. X-ray, C-scan are all becoming more common in modern aircraft structures.
Exactly. Have seen several times where x-ray or ultrasound was brought in to verify underlying fiber orientation or bond integrity when needed. Even Cirrus and Diamond still rely on a tap-test as part of their inspection programs. Too bad those aircraft don't come with their own composite tapping hammers like Eurocopter gave away years ago over a bulletin they had released. While I think composites are the future for most new ventures for various reasons, they still have their limitations when compared to the old-standby metal structures.