Definition
An official maintenance and operational record kept for an aircraft, in which required entries are made to document inspections, repairs, alterations, equipment checks, and other items mandated by regulation. Separate logbooks are typically maintained for the airframe, each engine, and each propeller.
Plain English
The written record that travels with an aircraft, showing what work has been done on it and what required checks have been completed. Pilots and mechanics both make entries in it, depending on what the regulations call for.
Context Anchor
Seen when recording aircraft maintenance, inspections, and navigation-equipment checks, including a VOR receiver check made with a VOR test facility.
Derivation
‘Log’ comes from the old shipping practice of throwing a wooden log overboard to measure a ship’s speed and recording the result in a ‘log book.’ The term carried over to aviation, where the logbook is still the official running record of the aircraft’s history.
Why Pilots Care
Documents that required equipment checks have been performed, supporting regulatory compliance and continued airworthiness.
Intuition Check
Do not confuse an aircraft logbook with a pilot logbook. The aircraft logbook belongs to the airplane and records the airplane’s condition and required checks; a pilot logbook belongs to the pilot and records the pilot’s flight experience.
Example Sentence 1
After completing the VOR accuracy check, the pilot recorded the date, place, bearing error, and signature in the aircraft logbook.
Example Sentence 2
The annual inspection entry in the aircraft logbook confirmed the transponder had been tested.