Definition
The federal regulation that governs how a pilot may operate an aircraft that has inoperative instruments or equipment. It sets out the conditions under which a flight may be conducted with items not working, including the use of an approved Minimum Equipment List (MEL), or, in its absence, a specific deactivation-and-placarding procedure that requires the pilot to determine whether the inoperative item is required by the type certificate, the airworthiness regulations, an airworthiness directive, or the kind of operation being conducted.
Plain English
The rule that tells a pilot what to do when something on the aircraft is broken. It explains when you are still allowed to fly, what equipment must be working, and how to properly deactivate, placard, and document anything that is not.
Context Anchor
Seen during preflight planning and aircraft airworthiness checks, especially when a light, gauge, radio, or other installed item is found not working before flight.
Derivation
“14 CFR” means Title 14 of the Code of Federal Regulations, the part of U.S. federal rules that covers aviation. “Part 91” is the part for general operating and flight rules, and “section 91.213” is the specific rule inside that part dealing with inoperative instruments and equipment.
Why Pilots Care
It directly affects the go/no-go decision by defining whether an aircraft with inoperative equipment can be flown or must be repaired first.
Analogy
Think of it like a street address for a rule. “14 CFR” is the rulebook, “part 91” is the neighborhood, and “section 91.213” is the exact house you need to visit.
Intuition Check
Do not read “part” here as a physical airplane part. In this citation, “part” means a major division of the federal aviation regulations, and “section” means the specific rule within that division.
Example Sentence 1
When the cabin landing light failed during preflight, the pilot referenced 14 CFR part 91, section 91.213 to determine whether the flight could legally continue.
Example Sentence 2
The maintenance technician reviewed 14 CFR part 91, section 91.213 before signing off the aircraft after repairing the inoperative equipment.