Definition
A unique identifier assigned by the manufacturer to a specific aircraft, engine, propeller, or component, used to distinguish it from every other unit of the same make and model. In a pilot's logbook, the aircraft serial number is one of the entries used to positively identify the specific aircraft flown.
Plain English
A one-of-a-kind number stamped on an aircraft or its parts by the maker, used to tell that exact unit apart from all others built like it.
Context Anchor
Seen in training records, logbook entries, aircraft documents, maintenance records, and FAA forms when a specific aircraft or training device must be identified.
Derivation
From 'serial,' meaning 'arranged in a series or sequence.' Manufacturers assign these numbers in order as units come off the production line, so each aircraft or component gets its own place in the sequence.
Why Pilots Care
Accurate recording of the serial number ensures flight time is credited to the correct aircraft, supports regulatory compliance, and allows proper tracking of airworthiness directives and maintenance history.
Intuition Check
A serial number is not the same as an aircraft’s registration marking or call sign. The registration marking identifies the aircraft for display and radio use; the serial number identifies the specific item in records.
Example Sentence 1
When logging the flight, she recorded the aircraft's make, model, and serial number from the data plate.
Example Sentence 2
Before signing off the lesson, the instructor verified the aircraft serial number against the registration certificate.