When is borescope-based VT appropriate?

• A. Inspecting interior tubes, cavities, or complex geometries where direct line-of-sight is not feasible.
• B. Inspecting exterior flat surfaces with direct view.
• C. Quick casual inspection of large, open areas.
• D. Only for jewelry inspection.

Answer: (C)

Borescope-based visual testing is most appropriate when you need to see into spaces you can’t view directly. A borescope lets you insert a small, protected optic into tubes, cavities, or complex geometries to observe interior surfaces and features that are hidden from the naked eye. This is essential for detecting cracks, corrosion, misalignment, or deposits inside engines, turbines, piping, and other hollow structures where a direct line-of-sight view isn’t feasible.

It wouldn’t be the right tool for exterior flat surfaces that you can inspect with an ordinary line-of-sight view, or for quick casual surveys of large open areas where a broad field of view is more efficient. Jewelry inspection is generally handled with specialized close-up lighting and magnification rather than a borescope.