Definition
Technical information used as the basis for a maintenance repair or alteration that has not been formally approved by the FAA, but is recognized as valid because it comes from a reliable source. Examples include manufacturer service letters, service bulletins, and information in advisory circulars. Acceptable data may be used for minor repairs and alterations, but not for major repairs or major alterations, which require approved data.
Plain English
Information a mechanic is allowed to use as a reference when doing minor work on an aircraft, but not for big jobs that change how the aircraft is built or performs.
Context Anchor
Seen in aircraft maintenance records, repair instructions, alteration paperwork, and discussions about whether a mechanic has the right information to perform or sign off work.
Derivation
From the everyday word 'acceptable,' meaning 'good enough to be used.' In maintenance language, it specifically means 'good enough to use for minor work, but not formally approved by the FAA.' The distinction between 'acceptable' and 'approved' is what makes this term meaningful.
Why Pilots Care
Pilots and owners checking maintenance logbooks need to know that major repairs and alterations require approved data, not just acceptable data. Using the wrong category of data can make a repair non-compliant and the aircraft unairworthy.
Grounding Statement
Acceptable data is about whether the source of maintenance information is suitable to rely on for the job being done.
Intuition Check
Acceptable does not mean “automatically approved.” It means the FAA will allow that information to be used in the right situation, but some work requires formally approved data instead.
Example Sentence 1
The mechanic referenced a manufacturer service letter as acceptable data when performing the minor repair on the cowling.
Example Sentence 2
AC 43.13-1B provided acceptable data for the minor repair on the control surface.