How frequently is a borescope inspection conducted on a gas turbine engine (GTE)?

The correct answer is semi-annually, which reflects the standard practice for conducting a borescope inspection on gas turbine engines. Borescope inspections are essential for the maintenance and health monitoring of gas turbine engines, as they allow technicians to visually inspect internal components without disassembling the engine.

Conducting these inspections semi-annually provides a balanced approach to ensuring the engine's integrity while accommodating operational schedules and maintenance resources. This frequency allows for timely detection of wear, damage, or other anomalies that could affect engine performance, thereby supporting optimal safety and efficiency.

More frequent inspections, such as quarterly or monthly, might not be practical for most operational environments due to cost, downtime, and resource allocation. Conversely, an annual inspection could potentially allow issues to develop further, resulting in possible operational risks or costly repairs. Therefore, the semi-annual frequency strikes a necessary compromise between thoroughness and efficiency in maintaining gas turbine engines.