Name a common non-destructive testing method used for detecting cracks.

Ultrasonic testing is a widely used non-destructive testing method for detecting cracks in materials, particularly in aircraft structural components. This technique employs high-frequency sound waves that are transmitted through the material. When there are imperfections such as cracks, the sound waves are reflected back, and the amount of energy lost during this process can be analyzed. This allows technicians to identify the size, location, and extent of internal flaws without needing to disassemble or damage the structure being inspected.

While X-ray imaging is also a common non-destructive testing method, it is used in different contexts and is more complex, requiring specialized facilities and safety precautions due to radiation exposure. Weld shear testing is primarily a destructive testing method that assesses joint strength, and visual inspection is limited to surface flaws. Ultrasonic testing is preferred in many structural applications due to its ability to provide precise information about subsurface conditions.