What type of inspection method can detect internal flaws in an aircraft structure?

Radiographic testing is the correct method for detecting internal flaws in an aircraft structure. This non-destructive testing technique uses X-rays or gamma rays to penetrate the material being examined. As these rays pass through the structure, they create an image on a film or digital sensor that can reveal internal defects such as cracks, voids, or inclusions that may not be detectable by visual inspection.

The strength of radiographic testing lies in its ability to provide a detailed internal view of structural components, which is crucial for ensuring safety and integrity in aircraft maintenance. By capturing the internal structure, it allows technicians to assess the condition of critical components without compromising their integrity.

Other inspection methods, such as visual inspection, have limitations as they can only identify surface flaws visible to the eye. Ultrasonic testing is effective for finding internal flaws as well; however, it uses sound waves rather than radiation. Magnetic particle inspection is primarily useful for detecting surface and near-surface defects in ferromagnetic materials and would not be suitable for a comprehensive assessment of internal flaws in a complex aircraft structure.