During borescope inspections, which internal components are evaluated?

• A. During borescope inspections, internal components are evaluated for damage, wear, or deposits in the compressor, combustor, and turbine.
• B. It only checks exterior casing.
• C. It checks fuel injection timing.
• D. It inspects oil viscosity.

Answer: (A)

Borescope inspections are all about looking inside the engine to assess the condition of the main flow-path components. You inspect the interior for damage, wear, or deposits on the compressor, combustor, and turbine. In the compressor, you’re checking for damaged or worn blades, chips, rubbing, or any foreign-object damage. In the combustor, you look for cracks in liners, fuel nozzle deposits, and excessive carbon or flame-holding surface wear. In the turbine, you examine blades and vanes for erosion, cracks, deposits, and rubbing. This internal view helps determine overall engine health and whether maintenance or repairs are needed before a problem escalates. The other options miss the point: borescopes look inside, not just at exterior casing; they don’t measure fuel-injection timing, and they aren’t used to judge oil viscosity.