ABSTRACT
Boroscope inspections are visual examinations subject to the experience of the individual and the quality of the instrument being used. Boroscopes are also available with either two-way (up and down) and four-way (up, down, left, and right) articulation. A boroscope inspection will provide the direction to either increase water washing efforts, overhaul the unit, or continue running the unit. It may be necessary to fabricate a piece of rigid tubing to guide the boroscope through the combustor to the turbine nozzles and blades. A flexible fiber-optic boroscope can be inserted through a first stage turbine nozzle for a good view of the first stage turbine blades. For convenience in assessing engine health, some manufacturers have installed boroscope ports in strategical locations throughout their engines. The tubing must have an inside diameter slightly larger than the outside diameter of the boroscope and long enough to extend from the fuel nozzle plane to the first stage turbine nozzle plane.
