Which statement best describes nondestructive testing in aviation?

• A. It checks only the exterior surfaces
• B. It checks the external and internal condition without changing airworthiness
• C. It is used to improve engine power
• D. It damages the part during testing

Answer: (B)

Nondestructive testing in aviation means evaluating a part or structure’s condition without causing damage or changing its airworthiness, using techniques that can detect surface and subsurface defects while keeping the part suitable for service. The strongest statement captures that idea: it assesses both exterior and internal condition without altering airworthiness. Techniques range from surface methods like visual inspection, dye penetrant, and magnetic particle to internal methods like ultrasonic testing and radiography, all aimed at finding cracks, corrosion, or other degradation without destroying the part. It isn’t about improving engine power, and it isn’t about damaging the part—the focus is on detecting issues while preserving serviceability.