What nondestructive testing method is used to determine the soundness of a bonded honeycomb repair?

The metallic ring test is a recognized nondestructive testing method specifically used to evaluate the integrity of bonded structures, such as honeycomb repairs in aircraft components. This method involves tapping the surface of the honeycomb with a small hammer or similar instrument. The sound produced during this tapping can help determine whether the bond between the honeycomb core and its outer skins is intact.

When the bond is strong, a solid sound is produced, indicating good adhesion. Conversely, if there are voids or delamination within the honeycomb structure, the sound will be dull or muted, signaling potential issues with the repair. This technique is favored for its simplicity and effectiveness in detecting faults without damaging the material being tested.

Other methods, while useful in certain contexts, do not specifically or efficiently assess the soundness of a bonded honeycomb repair. Thus, the metallic ring test stands out as the most appropriate choice for this inspection type.