The term "lockout" on the Synchro-Self-Shifting (SSS) clutch system means that the _________.

Correct Answer: Option A — SSS clutch will not engage

Lockout on an SSS clutch physically prevents the pawls from engaging the ratchet teeth. This feature is essential during maintenance or specific operational modes where the gas turbine must rotate without turning the main reduction gear or the propeller shaft, effectively isolating the engine from the propulsion train.