Delamination! Any testing available?

The most effective way to test for delamination is to "coin tap" the suspected area. I worked it composites mfg for 30 years and used all kinds of NDI equipment to test for disbonds or delaminated areas and I can tell you even with $500k ultrasonic equipment we still coin taped our bonded rotor blades and air frame structures to check for disbonds. A large washer or even a screw driver as a previous poster described will work also by continuously tapping across an area in a grid pattern until a change in sound is heard. A good bonded area will produce a ringing sound a disbonded area will sound like a thud. A moisture meter will tell you if moisture is present but will not tell you if the area is delaminated. Composite structures all absorb water unlike metal but that does not necessarily mean it is disbonded.