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CHAPTER 59  airworthiness directive management process and ALTERNATIVE METHOD OF COMPLIANCE

Section 3 Safety Assurance System: Processing Alternative Methods of Compliance Proposals to Airworthiness Directives

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3-4800    REPORTING SYSTEM(S). For all Title 14 of the Code of Federal Regulations (14 CFR) parts, use Program Tracking and Reporting Subsystem (PTRS) activity codes 3346 and 5346.

3-4801    OBJECTIVE. This section explains how to manage alternative method of compliance (AMOC) proposals for Airworthiness Directives (AD) for Flight Standards Service (AFS) aviation safety inspectors (ASI) and Aircraft Evaluation Group (AEG) personnel. This process includes guidance for:

    Advising AMOC requesters if an AMOC is necessary.

    Identifying who can approve an AMOC proposal.

    Differentiating between a transferable and non-transferable AMOC.

    Approving, denying, or revoking an AMOC.

    Handling AMOC proposals from other Civil Aviation Authorities (CAA) and foreign owners/operators.

    Handling requests for global AMOCs (also known as AMOCs of general applicability).

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    Requesting 24/7 support for AMOCs.

3-4802    BACKGROUND.

A.    Federal Aviation Administration (FAA) Authority. The FAA authority regarding the promotion of safe flight for civil aircraft may generally be found in Title 49 of the United States Code (49 U.S.C.) § 44701 et seq. (formerly, Title VI of the Federal Aviation Act of 1958 (FA Act) and related statutes). One of the ways the FAA has implemented its authority is through 14 CFR part 39, Airworthiness Directives. Specifically, the FAA issues ADs when an unsafe condition is found to exist in a product of a particular type design and the condition is likely to exist or develop in other products of the same type design.

B.    Conditions for Continued Operation. The FAA uses ADs to notify aircraft owners and operators of unsafe conditions and the actions required to address those conditions. ADs prescribe the conditions and limitations, including inspection, repair, or alteration under which the product may continue operation. ADs are authorized under part 39 and issued in accordance with the public rulemaking procedures of the Administrative Procedures Act (APA).

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NOTE:  Per 14 CFR part 21, § 21.1(b)(6), the word “product” means an aircraft, aircraft engine, or propeller. In addition, for the purposes of part 21 subpart L only, it includes components and parts of aircraft, aircraft engines, and propellers. This includes parts, materials, and appliances approved under the Technical Standard Order (TSO) system.

3-4803    APPLICABILITY OF ADs. Each AD contains an applicability statement specifying the product, including its make and model, to which it applies. Type certificate (TC) and airworthiness certification information are used to identify the product affected. Limitations may be placed on applicability by specifying the serial number or number series to which the AD is applicable. When there is no reference to serial numbers, all serial numbers are affected. FAA-IR-M-8040.1, Airworthiness Directives Manual, Chapter 8 defines the criteria for applicability.

A.    AMOC.

1)    An AMOC is an FAA-approved method of compliance, other than the one specified in an AD, to resolve an unsafe condition on a product while providing an acceptable level of safety. An AMOC may also change the time required to accomplish an AD.
2)    The AMOC process as prescribed in part 39 is an essential tool for resolving a safety concern. The AMOC process is controlled by the Aircraft Certification Service (AIR) per FAA Order 8110.103, Alternative Methods of Compliance (AMOC). It is important that both AFS ASIs and AIR Aviation Safety Engineers (ASE) understand their role in the AMOC process. To prevent possible conflicting influences, FAA personnel must be consistent in the review, approval, and application of the processes under their responsibility.

B.    When and Why an AMOC is Necessary.

1)    An AMOC may be proposed if an owner/operator cannot comply, or devises a different way to comply, with the actions specified in an AD.
2)    The reasons an AMOC may be necessary include, but are not limited to, the following:

    To accomplish AD actions in a way that better suits an owner/operator’s business processes.

    An owner/operator devises another or better way of addressing the unsafe condition.

    An owner/operator wishes to adjust the compliance time to an AD.

    Existing modifications, alterations, or repairs to a product make compliance with AD procedures difficult or impossible.

    To use later revisions of service documents specified in an AD.

    A superseding AD invalidates previous AMOCs to the original AD.

    To address errors in service documents.

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3-4804    THE AMOC APPROVAL PROCESS. The FAA allows an owner/operator to propose an AMOC to an AD, as seen in Order 8110.103, Chapter 3, Figure 1, AMOC Process Flowchart.

NOTE:  Order 8110.103 supersedes this section if conflicts exist between the two documents.

A.    Formal Application Stage.

1)    Handling AMOC Proposals. In accordance with part 39, § 39.19, and unless the FAA authorizes otherwise, requestors send proposals to their principal inspector (PI). The PI may add comments to the AMOC proposal, but cannot approve/disapprove it. The PI must forward a copy of the AMOC proposal to the manager of the FAA office identified in the AD, or its delegated representative. Requesters may at the same time send a copy of their proposal to the manager of the office identified in the AD. However, if requesters do not have a PI, such as a design approval holder (DAH), they must send the proposal directly to the manager of the FAA office identified in the AD.
2)    Proposal Methods. While a letter is preferred, the FAA office identified in the AD may also receive AMOC proposals by other means, such as email, fax, or telephone. (AMOC proposals received by telephone must still be documented.) An AMOC proposal should include the following:
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a)    The requester’s name and complete mailing address.
b)    The affected product(s), model designation(s), serial number(s) (if applicable), flight hours or cycles (if applicable), and State of Registry (if known).
c)    The AD number and specific AD paragraph(s) to which the proposal applies.
d)    A complete and detailed description of the AMOC proposal, including (where applicable):
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NOTE:  The term “article” is defined in § 21.1(b)(2).

    Article names.

    Article numbers.

    Article serial numbers.

    Descriptions of damage (e.g., fatigue cracks or corrosion).

    Existing or affected modifications, alterations, or repairs.

    Alternative inspection methods, including repeat intervals.

    Change in compliance times.

    Technical descriptions of alternative processes or procedures.

    Pictures and drawings.

    Other details necessary to define the acceptable level of safety that the AMOC will achieve.

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e)    Substantiating data showing why the FAA should determine that the proposed AMOC resolves the unsafe condition with an acceptable level of safety. Two examples are:

1.    Data demonstrating that a different inspection method will produce acceptable results.

2.    Analysis showing that a previously modified, altered, or repaired structure in the area addressed by the AD redirects the load paths to eliminate the potential for cracking (i.e., the unsafe condition) identified in the AD.

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f)    If requesters want to change their Airplane Flight Manual (AFM)/Rotorcraft Flight Manual (RFM), instruct them to submit the affected sections of the manual and the proposed changes.
g)    If requesters want to use later revisions of service documents not specified in an AD, then the proposal must include copies of those service documents and how the revised service documents provide an acceptable level of safety.
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h)    If requesters wish to allow the AMOC response to be shared with the DAH, the proposal must include a statement to that effect.
3)    Comments. After reviewing the proposal, the PI may confer with the AEG and should add any comments regarding:

    The unique nature of the operator’s operation.

    The operator’s ability to comply with the AMOC.

    Other information relative to the AMOC’s accomplishment that will assist the AEG and Aircraft Certification Office (ACO) in determining whether to approve the AMOC proposal.

NOTE:  The PI may conduct an on-site evaluation when deemed necessary to identify the compliance status of the AMOC proposal.

B.    Document Compliance Stage. Refer to Order 8110.103.

1)    The FAA assigns an ASE to evaluate the AMOC proposal.
2)    The ASE should ensure that the proposal provides an acceptable level of safety. When reviewing an AMOC proposal, the ASE should notify the requester’s PI as well as other ASIs for help evaluating any unique fleet or operational characteristics.

C.    Determining Whether AMOCs Should Transfer. If the AMOC proposal provides an acceptable level of safety and may be approved, the ASE should next determine if the AMOC is transferable. A transferable AMOC is not strictly tied to the requester/holder and follows a product to any new owners. The holder of a transferable AMOC document can give or sell the document to someone else. The ASE will follow Order 8110.103 when determining transferability.

D.    Notification of Approval. If approving the AMOC, the ASE must send an approval letter to the requester, plus a copy to the requester’s PI, unless it is a global AMOC.

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E.    Denying an AMOC Proposal. If the proposal does not meet the criteria stated in Order 8110.103, paragraph 3-11, then the ASE will send a denial letter to the requester, plus a copy to the requester’s PI.

F.    Revoking an AMOC. Although it should be rare, a previously approved AMOC may be revoked because it does not provide an acceptable level of safety. A revocation letter will not be issued for global AMOCs because it may not be possible to determine who received or used a global AMOC. In this case, it would be necessary to supersede the AD to revoke the AMOC if an unsafe condition exists. Refer to Order 8110.103, paragraph 4-2, for further information.

G.    AMOC Proposals from Other CAAs.

1)    If the AMOC proposal is for an AD issued by other CAAs, the FAA does not approve the proposal because it is the responsibility of the CAA that issued the AD. The ASE drafts a denial response per Order 8110.103.
2)    If an AMOC proposal is for an FAA AD for a foreign-registered aircraft, the ACO can approve the proposal, but authorizing use of the AMOC is the responsibility of the CAA of the State of Registry. Refer to Order 8110.103 for more information on AMOC proposals for foreign-registered aircraft.

3-4805    GLOBAL AMOCs (AMOCs OF GENERAL APPLICABILITY). As used in this order, a “global AMOC” is also defined as an AMOC of general applicability—a term used in some bilateral agreements. A global AMOC applies to two or more operators and can be used to obtain an AMOC for multiple serial numbers or makes and models specified in an AD. Global AMOCs can be useful if the responsible office receives or expects to receive multiple requests for the same AMOC. A global AMOC applies to, and is transferable with, the product to other owners/operators. Anyone, including someone other than an owner/operator, may propose a global AMOC. The following are some examples of global AMOC proposals:

    An operator proposes a global AMOC for the entire range of aircraft cited in the applicability section of an AD, which includes, and can be used by, other operators.

    A company proposes a global AMOC to repair multiple aircraft, even though the company is not the DAH for those aircraft.

    A type club proposes a global AMOC that can be used by multiple owners of a particular aircraft model.

    An individual proposes an AMOC for his or her aircraft that other owners of that same aircraft model can use because the proposal is of general applicability.

    The DAH for all aircraft affected by an AD develops a revision to the Service Bulletin (SB) mandated by the AD and proposes a global AMOC to allow all owners/operators of the aircraft to use the new revision. If the AMOC proposal is approved, the DAH can then notify the affected owners/operators by adding a statement in the SB revision describing which engineering aspects of the SB are an AMOC to the AD.

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A.    Criteria for Support. The 24/7 process is defined in Order 8110.103. This process is intended to provide urgent support and is exercised at the discretion of responsible ACO managers or their designees. This is not intended to be used to accommodate certificate holders who have failed to plan adequately for AD compliance. There are two qualifiers to implement the 24/7 process:

    AMOC support is needed after normal business hours and in order to support AFS inspectors; and

    AMOC support is needed to avoid significant air transportation disruptions or substantial impact to certificate holders.

B.    Request Support. Once the 24/7 criteria is met, AFS ASIs will refer to Order 8110.103 on how to contact AIR for support through the AEG. Since this is an FAA process, only the ASI, not the owner/operator, can request 24/7 AMOC support.


A.    References (current editions):

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    Title 14 CFR Part 39.

    FAA Order 8110.103, Alternative Methods of Compliance (AMOC). Reference AMOCs and the 24/7 process.

    Advisory Circular (AC) 39-7, Airworthiness Directives.

    FAA-IR-M-8040.1, Airworthiness Directives Manual.

B.    Forms. None.

C.    Job Aids. None.

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3-4808    TASK OUTCOMES.

A.    Complete the PTRS Record.

B.    Document The Task. File copies of corresponding documents in the aircraft owner/operator’s office file.


A.    Parts 121 and 135. For parts 121 and 135, follow Volume 10 guidance for planning and conducting future risk-based surveillance.

B.    Other 14 CFR Parts. For all other 14 CFR parts, plan and perform future inspections to ensure compliance, as necessary.

RESERVED. Paragraphs 3-4810 through 3-4822.