Definition
A section of Title 14 of the Code of Federal Regulations that lists the specific items a mechanic must inspect when performing an annual or 100-hour inspection on an aircraft. It serves as the minimum scope of inspection required by the FAA for those checks.
Plain English
It is the FAA's official checklist of what has to be looked at during an annual or 100-hour inspection. If it is on this list, the mechanic has to inspect it.
Context Anchor
Seen in aircraft maintenance, inspection signoffs, logbook entries, and discussions about annual or 100-hour inspections.
Derivation
CFR stands for Code of Federal Regulations, the published rules of U.S. federal agencies. Title 14 covers aeronautics. Part 43 covers maintenance. Appendix D is a specific attachment to Part 43 that spells out inspection scope.
Why Pilots Care
A pilot or owner needs to know the required inspection items to ensure the aircraft meets regulatory standards before flight and to understand what work was performed.
Intuition Check
Do not read this as just a book reference with no practical effect. In this context, it points to a required FAA inspection standard that mechanics must follow for annual and 100-hour inspections.
Example Sentence 1
The mechanic worked through the items in 14 CFR part 43, Appendix D before signing off the annual inspection.
Example Sentence 2
Before signing off the logbook, the owner reviewed 14 CFR Part 43, Appendix D to verify the scope of the 100-hour inspection.