Definition
An FAA-approved document, specific to a particular aircraft, that lists the instruments and equipment that may be inoperative while still permitting the aircraft to be flown legally and safely under defined conditions and limitations.
Plain English
A list that tells you which broken or missing items on your airplane you can still fly with, and under what conditions. If something is broken and it isn't on this list as allowed, the airplane cannot legally fly until it's fixed.
Context Anchor
Pilots encounter the MEL during preflight, after a maintenance issue is found, or after a rejected takeoff when deciding whether the airplane can legally and safely depart again.
Derivation
The name describes itself only in part. 'Minimum' here doesn't mean 'the least amount of equipment' — it means the minimum that must still be working for flight to be permitted. Everything not on the list must be operational.
Why Pilots Care
Determines whether a flight with inoperative equipment is legal and safe; operating without following the MEL can result in regulatory violations or unsafe conditions.
Grounding Statement
If something on the airplane is not working, the MEL is the approved go/no-go reference for whether flight is still allowed.
Intuition Check
Do not read “minimum equipment” as “the basic equipment every airplane must have.” In this context, the MEL mainly lists items that may be allowed to be not working, and the conditions that must be met before flight.
Example Sentence 1
During preflight the pilot found the landing light inoperative, checked the MEL, and confirmed the aircraft could be dispatched for the daytime flight with that item placarded.
Example Sentence 2
Per the MEL, the flight was permitted to continue after one fuel gauge failed, provided the remaining gauge was verified accurate.