Definition
A Minimum Equipment List is an FAA-approved document, specific to a particular aircraft make and model, that identifies which items of equipment may be inoperative and still allow the aircraft to be legally flown, along with any conditions, limitations, or maintenance procedures that must be followed. An MEL is approved by the FAA for a specific operator and, once adopted, replaces the equipment requirements of 14 CFR 91.213(d) for that aircraft.
Plain English
A list, approved for a specific aircraft, that tells the pilot exactly which broken or missing items still allow the airplane to be flown legally, and under what conditions.
Context Anchor
Seen when deciding whether an aircraft with a failed instrument, system, or item of equipment may still be flown legally and safely.
Derivation
‘Minimum’ comes from the Latin minimus, meaning ‘least.’ The name reflects the idea of the least equipment that must be working for the flight to be legal — anything below that line, and the aircraft cannot go.
Why Pilots Care
It decides whether a flight can legally and safely depart with certain systems unavailable.
Intuition Check
Do not read “minimum equipment list” as a list of everything the aircraft must have before every flight. In this FAA use, it is mainly a controlled list of items that may be not working and still allow flight under stated conditions.
Example Sentence 1
When the copilot’s landing light failed during preflight, the captain consulted the MEL and confirmed the flight could continue with the light placarded inoperative.
Example Sentence 2
With one generator offline the crew confirmed the MELs allowed continued flight to the destination airport.