Borescope Inspections

Aircraft turbines are susceptible to various forms of damage, including ingested foreign objects (FOD), corrosion, erosion, thermal deterioration, cracking, and distortion. As the components most at risk are not easily visible through unaided visual inspection, the primary method for assessing turbine condition involves the use of a borescope.

Borescope inspections of aircraft turbines are standard procedures to detect signs of wear, thermal, and mechanical damage. These inspections contribute to maintaining the reliability of aircraft gas turbines, enhancing safety and extending the operational lifespan of engines without the need for costly and time-consuming tear-downs and unnecessary maintenance. Many aircraft turbine borescope inspections are now mandated by the FAA and manufacturers.

Key areas of borescope inspection include:

Compressor: Access points for borescope examination include the air inlet, bleed port, or specially designed borescope port. Inspection of compressor blades and guide vanes for foreign object damage (FOD) and erosion, focusing on leading and trailing edges.

Combustion Chamber: Examination of burner cans for cracks and misalignment. Checking fuel nozzles, louvers, and other components for excessive coking, cracking, and distortion. Access is typically through an ignitor port.

Turbine Section:  High heat levels in the first stage turbine necessitate scrutiny of stationary nozzles and guide vanes for burning, cracking, FOD, pitting, erosion, and sulfidation. Second stage blades may be subject to shifting and rivet cracking. Access is typically through an ignitor port or a specifically designed borescope port.

By employing these inspection techniques, aviation professionals can effectively monitor and address potential issues, ensuring the continued safe and efficient operation of aircraft turbines.