After completing a bonded honeycomb repair, what nondestructive testing is used to test the soundness of the repair?

The metallic ring test is considered the appropriate nondestructive testing method for evaluating the soundness of a bonded honeycomb repair. This technique involves tapping on the surface of the material and listening for the resultant sound. A solid, properly bonded repair will produce a consistent, ringing sound, while any delamination or voids within the honeycomb structure will create a dull or muted sound. This test is particularly effective because it is simple, quick, and does not require any specialized equipment beyond a simple metallic ring or hammer for tapping.

Visual inspection alone may not reliably reveal internal defects or bonding issues, as it primarily reflects the external condition of the surface. Ultrasonic testing provides a more detailed examination and is effective for many materials, but it may not be as effective or convenient for the specific characteristics of bonded honeycomb structures. Magnetic particle inspection is typically used for ferromagnetic materials and is not suitable for testing non-metallic composites like bonded honeycomb materials. Therefore, the metallic ring test is the most suitable choice for assessing the integrity of such repairs.