Honeycombs repair methods

Repair methods K B ARMSTRONG Methods for composites and honeycomb panels on large structures such as aircraft... 

This method can detect both near-side and far-side unbonds in many types of honeycomb and laminar structures. It can also detect crushed core, fractured core, and excessive build-up in repaired structures. At least one of the surfaces must be electrically conductive to some extent. 

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