What could be a potential consequence of moving the PCL above idle before N1 stabilizes?

Moving the Power Control Lever (PCL) above idle before the N1 (engine fan speed) stabilizes can lead to an increased risk of engine compressor stall. When the PCL is advanced too quickly, the airflow through the engine may not be sufficiently established to match the increased fuel flow and power output demanded by the higher PCL setting. This mismatch can result in abnormal airflow patterns and pressure changes within the engine, which are conducive to a compressor stall.

Compressor stalls occur when there is a disruption in the smooth flow of air through the engine compressor, leading to a reduction in thrust and potentially damaging conditions for the engine. On the T-6A, careful management of the PCL and monitoring the N1 stabilization is crucial to ensure reliable and safe engine performance, highlighting the importance of understanding engine response to power changes. This emphasizes the significance of adhering to proper operating procedures, particularly during critical phases of flight.