11-1 CHAPTER 11. CONFIGURATION DEVIATION LIST (CDL)
11.1 Purpose of the CDL. The CDL is a list of externally exposed nonstructural aircraft parts that may be missing, and is tailored for each model aircraft. The CDL evolved over several years from what was commonly known as a “missing parts list,” which was a list of nonstructural external parts of an aircraft that were found missing after flight. A CDL allows continued operation with missing externally exposed nonstructural parts by defining restrictions, limitations, or performance penalties, while the aircraft remains airworthy.
11.2 Development. The aircraft manufacturer develops a CDL during the initial certification process. This is not a requirement for aircraft certification. The manufacturer makes the decision to develop or not to develop a CDL. The responsible Aircraft Certification Service office has final approval of all FAA-approved CDLs and all requests for revisions to an FAA-approved CDL.
11.2.1 Which Aircraft Has a CDL. A CDL is developed for most U.S.-built transport category part 25 aircraft and many part 23 aircraft by aircraft manufacturers during the initial certification process. If deemed necessary, the aircraft manufacturer develops a proposed CDL and coordinates submission with the responsible Aircraft Certification Service office and the Aircraft Evaluation Division (AED). The responsible Aircraft Certification Service office and the AED review, evaluate, and may conduct or oversee any required testing and data collection necessary to approve proposed CDL items. Approval of a CDL is by the responsible Aircraft Certification Service office or through an Original Equipment Manufacturer’s (OEM) Organization Designation Authorization (ODA) program.
11.2.2 U. S. -Manufactured Aircraft. For U.S.-manufactured aircraft, an FAA-approved CDL is either:
• Incorporated into the limitations section of the Airplane Flight Manual (AFM);
• Published as an appendix to the AFM; or
• Published as a supplement to the AFM.
11.2.3 Aircraft Manufactured Outside the United States. The CDL may be a standalone document that is part of the Structural Repair Manual or other manufacturer’s document.
11.3 Operator Use of the CDL.
11.3.1 FAA-Approved CDL. An operator may use a CDL and incorporate it into its manual system. However, the manufacturer’s CDL is already approved by the responsible Aircraft Certification Service office and therefore, will not be approved or accepted by the responsible Flight Standards office. It should not appear on the List of Effective Pages (LEP) of an operator’s MEL or any other documents showing approval or acceptance by the responsible Flight Standards office. The manufacturer’s CDL may be
11-2 attached to the operator’s MEL, but should be treated as a separate and “standalone” document.
11.3.1.1 The manuals used by flightcrew members, maintenance personnel, and dispatch personnel should include instructions governing CDL use. An operator may increase fuel and performance penalties or add additional limitations and restrictions beyond what is already required in the FAA-approved CDL. These additional penalties, limitations, and restrictions may be listed in the operator’s manual system and should be submitted to the responsible Flight Standards office for approval or acceptance. Such additions should be delineated as “operator-specific” requirements and under no circumstances be less restrictive than the FAA-approved CDL.
11.3.1.2 If an operator desires an amendment to the manufacturer’s CDL, such requests may be coordinated with the responsible Aircraft Certification Service office through the responsible Flight Standards office, directly with the responsible Aircraft Certification Service office, or directly with the aircraft manufacturer.
11.3.2 O perator- Specific CDL. An operator may also choose to create an operator-specific CDL for use in its operation, using the FAA-approved CDL’s data. Operators creating their own operator-specific CDL should not confuse this CDL with the official FAA-approved CDL or make it less restrictive than the FAA-approved CDL. Operator-specific CDLs will be accepted by the responsible Flight Standards office and be incorporated into an operator’s manual system.
11.4 O perato r’s Manual. Operators should consider having policies and procedures in their manual system regarding use of the CDL, such as:
• A description of how the CDL is applied and utilized in their operation.
• Instructions on where to access current FAA-approved CDLs for specific model aircraft and future revisions.
• Methods for the proper application of fuel and performance penalties, procedures, or restrictions and limitations while conducting flight operations utilizing the CDL.
• A page control system to show that the operator-specific CDL is current and complete (if one has been developed by the operator).
• A page control system associated with the manufacturer’s CDL that is approved by the responsible Aircraft Certification Service office.
• The policies and procedures may be combined within the operator’s approved MEL management program procedures.
11.5 CDL Item Recording and Notifications. Operators should establish a standard procedure for advising flightcrews, aircraft dispatchers, and maintenance personnel of an aircraft’s status with current CDL and MEL issues along with the conditions and limitations that apply.
11-3
11.5.1 R eporting of Found CDL Items. If a CDL item(s) is discovered missing by:
11.5.1.1 Maintenance Person Positioned at the Aircraft. If a CDL item is discovered missing by maintenance personnel, that person notifies the flightcrew and the maintenance organization (e.g., Maintenance Control).
11.5.1.2 Flightcrew. If a CDL item is discovered missing by the flightcrew, the flightcrew notifies the maintenance organization and appropriate flight operations personnel.
Note: The maintenance organization or flightcrew notifies flight operations personnel (e.g., dispatch, flight following, or other persons authorized to exercise operational control) in accordance with the aircraft operator’s approved MEL or CDL procedures.
11.5.2 L ogging and Notification Requirements. Each missing CDL item is entered into the aircraft maintenance logbook and listed on a placard, which is then affixed in the cockpit in clear view of the flightcrew, per the AFM. Principal Operations Inspectors (POI) may allow operators to use their MEL procedures for addressing an aircraft’s CDL status and limitations. Such procedures will conform to the AFM CDL placarding requirements.
11.5.3 Fuel and Performance. Fuel and performance penal ties, limitations, and restrictions associated with each CDL item are calculated and entered in the appropriate flight documentation (e.g., dispatch, flight release, or flight plan). If flight documentation has been issued prior to the application of the CDL item, the operator will ensure that fuel and performance planning are recalculated in accordance with the CDL item, if applicable. Operators conducting part 121 operations should issue a new or amended dispatch or flight release to include these penalties.
Advisory Circular Feedback Form If you find an error in this AC, have recommendations for improving it, or have suggestions for new items/subjects to be added, you may let us know by contacting the Air Transportation Division at 9-AFS-200-Correspondence@faa.gov or the Flight Standards Directives Management Officer at 9-AWA-AFB-120-Directives@faa.gov.
Subject: AC 120-125, Development and Use of an Operator’s MEL, NEF Program, and CDL for Operations Under 14 CFR Parts 91K, 121, 125, and 135 Date: _____________________ Please check all appropriate line items:
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