Definition
An aircraft component that has a published maximum service life, expressed in operating hours, calendar time, or operational cycles, after which it must be removed from service and replaced or overhauled regardless of its apparent condition.
Plain English
A part that has to be retired or replaced once it reaches a set age or amount of use, even if it still looks and works fine.
Context Anchor
Seen in aircraft maintenance records, inspection programs, logbooks, and parts replacement planning.
Why Pilots Care
Failure to track and replace these parts on schedule can ground the aircraft or create an unsafe condition in flight.
Analogy
Think of it like a hard expiration date on important safety equipment. It may still look fine, but once the allowed time is up, you do not keep using it.
Intuition Check
Do not assume “time-limited” means the part is only inspected after a certain time. It means the part has a maximum allowed service life and must be removed when that limit is reached.
Example Sentence 1
Before the flight, the mechanic checked the logbook to confirm no time-limited part on the engine was approaching its replacement interval.
Example Sentence 2
Before the preflight, the pilot reviewed the logbook to confirm no time-limited parts were approaching their replacement interval.