What Is MSN? Definition & Meaning in Aviation
MSN (manufacturer serial number) is the unique number a manufacturer gives to each aircraft it builds.
In plain language
It stays with the airframe for life, even when the aircraft changes airline and registration. It helps track an aircraft’s history.
Example
Two aircraft of the same type owned by different airlines can be told apart by MSN even if their registrations change.
Why it matters
The MSN follows an airframe through owners and registrations, which makes it the most reliable way to trace an individual aircraft’s history, from the factory to retirement.