Plain English Meaning

A written history book for the airplane's engine. It records every inspection, repair, and overhaul the engine has had, plus how many hours it has run. The pilot checks it during preflight to make sure the engine is legal and safe to fly.

Full Definition

Permanent maintenance records kept for each engine installed on an aircraft, documenting total time in service, inspections performed, repairs, overhauls, replacement of life-limited parts, airworthiness directive (AD) compliance, and any other actions affecting the engine's airworthiness. Engine logbooks are required by 14 CFR Part 91 and are maintained separately from the airframe logbook so that the engine's history travels with the engine if it is removed and installed on another aircraft.