With the decline in coal-fired power generation over the last two decades in favor of renewable power, combustion turbines in both simple-cycle and combined-cycle configurations are serving as an important bridge technology for grid stability. A critical aspect of gas turbine operation is optimized inlet air flow. Poor intake design/maintenance or off-design operation can result in inefficient air compressor and turbine performance. Other issues may cause corrosion or fouling throughout the unit. Important air intake components include the ductwork, air filters (usual but not universal), silencer, and for many units, an inlet air cooler. This article outlines inspection/maintenance techniques to ensure that equipment is in proper condition.