• Minimum Equipment Lists (MEL) and Master Minimum Equipment Lists (MMEL)

    EASA OPS ORO.MLR.105 specifies the requirements for producing a Minimum Equipment List (MEL) from the Master Minimum Equipment List (MMEL).

    For Air Navigation Order (ANO) operators, ANO 2016 Article 78 applies and a formal Permission is issued by the CAA.

    Submitting the MEL for approval

    The operator should submit the:

    • the MEL for approval; together with
    • the associated MMEL - which must be confirmed by the operator to be the latest version; and
    • the MEL Compliance Statement.

    This submission should be emailed to: npa@caa.co.uk.

    The MEL is reviewed jointly by the assigned Flight Operations Inspector, Airworthiness Surveyor and Operational Support Officer.


    Where there is an EASA MMEL this should be used as the source document, but the operator must ensure that where operational procedures, and where applicable the maintenance procedures, are required to be developed by the operator, these are detailed in the MEL.

    In the preamble, circumstances in which the flight crew can dispatch with an unserviceable item, must be specified. A system for determining whether items are non-safety related must also be developed and included in the MEL.

    If no EASA approved MMEL exists for a particular type then the MMEL accepted by the CAA will be the latest issue of the Type Certificate Holder’s MMEL approved by their Primary Certificating Authority. For Type Certificate Holders approved by the United States as the State of Design, this would be the FAA MMEL.

    If an EASA approved MMEL is subsequently published it will replace the non-EASA MMEL as the accepted document. Where the Type Certificate Holder is a UK company (i.e. BAe Systems, Britten-Norman, Bombardier Aerospace Short Brothers) the National Authority is the UK CAA, thus the manufacturers MMEL is already approved by the CAA.

    Certain items in the non-UK Type Certificate Holders’ MMELs may require modification to comply with European operating rules. This is permissible through the use of EASA MMEL policies published in CS-MMEL. This is available online: CS-GEN-MMEL Generic Master Minimum Equipment List.

    In addition a number of MMEL items for specific aircraft types are associated with UK certification requirements and need to be retained. This would be where there are notified UK national requirements as published in the aircraft Aircraft Flight Manual (AFM).

    For certain types (e.g. Saab 340 or Falcon 20) the removal of the CAA generated MMEL and reversion to the Type Certificate Holder’s MMEL may have an effect on Rectification Interval Extensions (RIE). RIE allow operators to permit a one-time extension of the applicable RI category B, C or D, for the same duration as that specified in the MEL provided that the source MMEL allows RIE. RIE requires separate approval from the CAA and any application is reviewed jointly by the assigned FOI and AS. The application should be made in writing to the assigned FOI.

    Where a CAA approved MMEL is produced by a UK Type Certificate Holder, this should be used as the source document for producing the operator’s MEL.

    State emergency services helicopters

    For the operation of state emergency services helicopters, the requirements for flight recorder standards are listed in the CAA Specification No. 23. The corresponding items for CVR, FDR and combination recorders in EASA CS-MMEL, which perform similar functions, may be used as a guideline.