What is the maximum N1 with the PMU on?

The maximum N1 setting when the PMU (Power Management Unit) is engaged is indeed 104%. This value is critical for ensuring optimal engine performance while preventing potential damage. The PMU is designed to manage the engine's thrust output by adjusting various parameters, including N1, which is the rotational speed of the fan and the low-pressure compressor. Operating at 104% N1 allows for maximum thrust during takeoff and critical phases of flight without exceeding the engine's design limits, thus maintaining safety and efficiency.

The values listed for options reflect different operational thresholds, but only 104% is the established maximum with the PMU on. It’s essential for pilots to adhere to this specification to ensure consistent engine performance and longevity while also aligning with operational guidelines and limitations.