What reduction in climb performance may be observed with the defog ON and the PCL retarded to maintain ITT within limits?

When the defog is activated in the T-6A Texan II, there is an increase in electrical load due to the operation of the dehumidification and heating systems. This increased load can affect the engine's performance, specifically its ability to maintain climb performance. When the power control lever (PCL) is retarded to keep the Interstage Turbine Temperature (ITT) within limits, it reduces the power output from the engine.

The specific figure indicating a 47% reduction in climb performance is derived from operational characteristics and performance charts associated with the T-6A. Pilots should be aware that such performance degradation impacts their operational capabilities and requires adjustments in flight profiles or tactics. By understanding this significant reduction, pilots can make informed decisions regarding energy management and situational awareness while flying in conditions requiring defog usage.