Definition
The section of the Federal Aviation Regulations that sets out the maintenance, preventive maintenance, and alteration requirements for civil aircraft operated under Part 91 (general operating and flight rules). It defines who is responsible for keeping an aircraft airworthy, what inspections are required, who may perform them, and the recordkeeping that must accompany them.
Plain English
It is the part of the regulations that tells aircraft owners and pilots what inspections, maintenance, and records are required to keep a private or general aviation aircraft legal and airworthy.
Context Anchor
Seen in aircraft inspection, maintenance responsibility, and airworthiness discussions, especially when the handbook explains what an aircraft owner or operator must do.
Derivation
CFR stands for Code of Federal Regulations -- the official collection of U.S. government rules. Title 14 covers Aeronautics and Space. Part 91 covers general flight rules for most civil aircraft, and within Part 91, Subpart E groups the rules specifically dealing with maintenance and inspections.
Why Pilots Care
Pilots must confirm their aircraft meets these requirements to remain legal and safe for the intended flight.
Intuition Check
“Part” and “subpart” do not mean casual pieces of a book here. They are formal divisions of federal aviation law, and this one points specifically to maintenance and inspection requirements under part 91.
Example Sentence 1
Before signing off the aircraft as ready for flight, the owner reviewed 14 CFR part 91 subpart E to confirm the annual inspection was current.
Example Sentence 2
Maintenance logs showed the airplane fully complied with 14 CFR part 91 subpart E before the annual inspection was signed off.