Aviation glossary
MEL
Minimum Equipment List — the list of equipment that may be inoperative while still allowing the aircraft to operate. Prepared by the operator and approved by the authority.
The MEL (Minimum Equipment List) is derived from the manufacturer's Master MEL (MMEL) and tailored to a specific operator and type. It defines which instruments or systems may be temporarily inop, under what conditions and for how long (categories A/B/C/D by allowed rectification interval). Without an approved MEL every item listed in the type certificate and AFM must be fully operative before flight. The MEL is part of the operational documentation carried on board.