What type of logbook would typically contain the operating history of an aircraft's engine?

The engine logbook is specifically designed to record the operating history, maintenance, and any alterations made to the aircraft's engine. This logbook includes essential information such as the engine's serial number, total flight hours, maintenance checks, repairs conducted, and any replacement of parts. Keeping a detailed engine logbook is critical for tracking the performance and reliability of the engine over time and ensuring compliance with regulatory requirements.

In contrast, the airframe logbook primarily focuses on the airframe and its structural components, the maintenance logbook records overall maintenance activities of the aircraft as a whole, and the pilot's logbook is used by pilots to track their flight time and experience rather than engine-specific details. Hence, the engine logbook is the most appropriate choice for documenting the operating history of an aircraft's engine.