AC 39-10

Advisory circular · Alternative Methods of Compliance

Approved
September 14, 2016
Last reviewed
September 16, 2016
Family
AC 39-10 · 1 version
14 CFR parts
3, 21, 25, 39, 43, 91, 121, 135
Cited by
1 AD

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed October 23, 2026.

Show pages 1–12

3-1 CHAPTER 3. THE AMOC PROPOSAL

3.1 General.

This chapter provides the requirements and the process for submitting an AMOC proposal. It includes the minimum requirements for what an AMOC proposal must contain, and to whom and where to submit the proposal.

3.2 Requirements for an AMOC Proposal.

Anyone may propose an AMOC according to § 39.19. An AMOC proposal is not considered complete until the required information is received. The proposal must include the following:

3.2.1 The requester’s name and complete mailing address.

3.2.2 The affected products, model designations, serial numbers (if applicable), flight hours or cycles (if applicable), and State of Registry (if known).

3.2.3 The AD number and specific AD paragraphs to which the proposal applies.

3.2.4 A complete and detailed description of the AMOC proposal, including the following (where applicable):

3.2.4.1 Article name.

3.2.4.2 Article numbers.

3.2.4.3 Article serial numbers.

Note: The term “article” is defined in 14 CFR 21.1(b)(2), Amendment 21-92.

3.2.4.4 Descriptions of damage (such as fatigue cracks or corrosion).

3.2.4.5 Existing or affected modifications, alterations, or repairs.

3.2.4.6 Alternative inspection methods, including repeat intervals.

3.2.4.7 Change in compliance times.

3.2.4.8 Technical descriptions of alternative processes or procedures.

3.2.4.9 Pictures and drawings.

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

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3.2.5 Substantiating data showing that the proposed AMOC resolves the unsafe condition with an acceptable level of safety. Two examples are—

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

3.2.5.2 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 (the unsafe condition) identified in the AD.

3.2.6 If the requester wants to change their airplane/rotorcraft flight manual, the affected sections of the manual and the proposed changes.

3.2.7 If the requester wants to use later revisions of service documents specified in an AD, copies of those service documents and how the revised service documents provide an acceptable level of safety.

3.2.8 If the requester wishes to allow the AMOC response to be shared with the DAH, a statement to that effect. Refer to paragraph 4.8 of this AC.

3.2.9 If the proposal is for an AMOC to an appliance AD, such as for an approved TSO article, a statement regarding the installation approval of the modified article (that is, whether the modified TSO article has been approved for installation or whether additional approval is required of the installer). Refer to paragraph 4.9 of this AC.

3.3 Who Approves an AMOC?

The manager of the FAA office identified in the AD has the authority to approve AMOCs to the AD. The following are some cases in which other persons may approve an AMOC:

3.3.1 The Aircraft Certification Office (ACO) has authorized a designee. Some ACOs authorize certain company designated engineering representatives (DER) or type certification Organization Designation Authorization (ODA) holder unit members to review and approve AMOC proposals. For information on what the ODA holder or DER can do within this delegated authority, refer to FAA Order 8100.15, Organization Designation Authorization Procedures, and FAA Order 8110.37, Designated Engineering Representative (DER) Handbook.

3.3.2 A different FAA office manager is responsible. Sometimes the responsibility for the type design of a product transfers from one FAA office to another FAA office, such as when a type certificate is transferred. When this happens, the responsibility for approving AMOCs for that product also transfers with the type design. Therefore, when the office identified in the AD receives an AMOC proposal for a product that has transferred, that office is responsible for forwarding the AMOC proposal to the currently responsible certificate managing office for approval/denial of the AMOC.

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3.4 Where to Submit.

Send your AMOC proposal to—

3.4.1 Your local PI. If you are an owner or operator, or otherwise have an airworthiness PI for either maintenance or avionics, you must submit your proposal through your PI.

Your PI is the person in the FAA most familiar with your operations and can add insight into your request that may be helpful to the ACO when reviewing your proposal. In addition, you may send your proposal to the manager identified in paragraph 3.4.2 below; however, this does not relieve you of your obligation to send your proposal to your PI.

3.4.2 The manager of the FAA office identified in the AD. If you do not have a PI (for example, if you are a DAH), you must submit your proposal directly to the office responsible for approving AMOCs. Send your proposal to the attention of the person identified in the Related Information section of the AD. Alternatively, if the FAA has notified the public (typically via letter to industry organizations) of the transfer of either the type certificate or of continued operational safety responsibilities, your proposal should be sent to the newly identified office to avoid unnecessary delays.

3.4.3 An authorized designee of the FAA. The AD will identify if AMOC approval authority is delegated. For older ADs that do not include an AMOC delegation section, contact the office identified in the AD to see if AMOC approval has been delegated.

3.4.4 The manager of the Military Certification Office (MCO), ACE-MCO-100M, if your proposal concerns a military commercial derivative aircraft (MCDA). Refer to paragraph 4.6 of this AC for more information.

3.5 AMOC Submittal Methods.

The FAA office or authorized designee identified in the AD may receive AMOC proposals via the following methods: letter, email, fax, or telephone call. Please note that the FAA or authorized designee may request that any AMOC proposal made via telephone be followed up by one of the other methods mentioned above. In any case, you must provide the information identified in paragraph 3.2 of this AC.

3.6 The AMOC Response.

All complete AMOC proposals will receive one of the following responses:

3.6.1 AMOC responses will either be in email or letter format, at the discretion of the FAA.

3.6.2 An authorized designee will provide a signed FAA Form 8110-3 or 8100-9 as appropriate.

3.6.3 Any proposal that does not provide an acceptable level of safety will be denied.

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3.6.4 If the FAA or authorized designee determines that the proposal provides an acceptable level of safety, it will issue an approval response. You may not use an AMOC until you have actually received a copy of the AMOC response. A verbal response from the FAA or authorized designee is not acceptable.

4-1 CHAPTER 4. OTHER AMOC CONSIDERATIONS.

4.1 General.

This chapter provides guidance on the following topics:

 Global AMOCs,  Returning aircraft to service,  Revoking an AMOC,  Foreign registered aircraft,  MCDA,  24/7 AMOC support,  Sharing AMOCs with DAHs,  AMOCs for appliances including TSO-approved articles, and  Previously approved AMOCs.

4.2 Global AMOCs (AMOCs of General Applicability).

A global AMOC applies to the product and is transferable with the product to other owners/operators. Anyone, including someone other than an owner/operator, may propose a global AMOC.

4.2.1 The following are some examples of global AMOC proposals:

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

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

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

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

4.2.1.5 The DAH for all aircraft affected by an AD develops a revision to the 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 may then notify the affected

4-2 owners/operators by adding a statement in the SB revision describing which engineering aspects of the SB are an AMOC to the AD.

4.2.2 Is an AMOC Applicable to an Operator’s Fleet of Aircraft the same as a Global AMOC?

An AMOC applicable to an operator’s fleet of aircraft is not a global AMOC, but rather an individual AMOC that applies to multiple aircraft operated by a single operator.

4.2.3 Frequently Asked Questions.

4.2.3.1 Question: Who can apply for a global AMOC?

Answer: Anyone may apply for a global AMOC.

4.2.3.2 Question: The DAH of my aircraft received a global AMOC for the engineering aspects of its service document. Do I need to propose another AMOC if I use the same service document?

Answer: No. If you use the service document as an AMOC, you are responsible for notifying your PI (or lacking a PI, the manager of the FSDO/Certificate Holding District Office [(CHDO]) before using it.

4.3 Returning Aircraft to Service.

4.3.1 You are responsible for notifying your PI (or lacking a PI, the manager of the FSDO/CHDO) before you use an AMOC. You may have additional requirements for maintenance recordkeeping for methods of compliance to an AD (for example 14 CFR 43.9, 14 CFR 91.417(a)(2)(v), 14 CFR 121.380(a)(2)(vi), or 14 CFR 135.439(a)(2)(v)).

4.3.2 You may approve your aircraft for return to service after accomplishing an AMOC only if you record the AMOC in your aircraft maintenance records as your method of compliance with the AD. Annotate the maintenance records with an applicable statement as follows:

4.3.2.1 “AMOC approval from the [XXX] ACO (or Directorate) approval authority, dated [MM-DD-YYYY],” or

4.3.2.2 “AMOC approval, FAA Form 8110-3, Statement of Compliance with the Federal Aviation Regulations, dated [MM-DD-YYYY] from [company DER name and employer],” or

4.3.2.3 “AMOC approval, FAA Form 8100-9, Statement of Compliance with Airworthiness Standards, dated [MM-DD-YYYY] from [ODA holder’s name],” or

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4.3.2.4 “Global AMOC approval from the [XXX] ACO (or Directorate) approval authority to [global AMOC requester’s name], dated [MM-DD-YYYY],” or

4.3.2.5 “Global AMOC approval from the [XXX] ACO (or Directorate) approval authority to [global AMOC requester’s name], pursuant to paragraph [XXX] of FAA-approved Service Bulletin [XXX], revision [XXX], dated [MM-DD-YYYY].”

4.3.3 Question: Do I need an AMOC if I deviate from the AD before the required compliance time?

Answer: Maybe. Before the AD compliance time, changes/modifications to a product may be accomplished via acceptable methods (such as an operator’s approved maintenance program). However, if AD compliance will be noted upon completion of this maintenance, even if it is before the required compliance time, and you have deviated from the steps required by the AD, you need an AMOC. If you do not note compliance with the AD at this time, no AMOC is necessary. Compliance with the AD, and a corresponding AMOC, will be required by the compliance time noted in the AD.

4.4 Revoking an AMOC.

If the FAA determines that a previously approved AMOC no longer provides an acceptable level of safety, the AMOC will be revoked.

4.4.1 The AMOC holder will receive a certified letter from the FAA with details regarding the revocation and any timeframes associated with it.

4.4.2 If an AMOC is revoked and a new AMOC is not approved in its place, the compliance actions stated in the AD must be met.

4.4.3 The FAA will not revoke a global AMOC because it may not be possible to determine who received or used it. If a global AMOC is found to no longer provide an acceptable level of safety, a new AD will be issued to revoke the AMOC.

4.5 Foreign Registered Aircraft.

Anyone may apply for an AMOC for a foreign (non-U.S.) registered aircraft.

The FAA issues AMOCs on foreign registered aircraft because it can minimize urgent proposals in the future should the aircraft join the U.S. registry.

4.5.1 The FAA only approves AMOCs to FAA ADs.

4.5.2 The FAA cannot approve AMOCs to another civil aviation authority’s AD.

4.5.3 Submit the required information in paragraph 3.2 of this AC to the appropriate person identified in paragraph 3.4.2 or 3.4.3 of this AC.

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4.6 Military Commercial Derivative Aircraft.

The responsible military airworthiness authority may request an AMOC to meet the provisions of an AD differently than the civil sector.

4.6.1 Submit the information in paragraph 3.2 of this AC to the MCO.

4.6.2 The FAA cannot approve AMOCs to any mandatory airworthiness action issued by the military.

4.6.3 If the AMOC is approved, a copy of it must be kept in the aircraft maintenance records. This will facilitate an AD compliance determination if the aircraft owner/operator later requests civil registration.

4.7 24/7 AMOC Support.

4.7.1 In September 2010, the FAA implemented a process to support an urgent need for AMOC issuance after normal business hours to avoid significant air transportation disruptions or substantial impact to an operator. Although a 24/7 AMOC support process is available, it is not intended to be used to accommodate air carriers or owners/operators that have failed to adequately plan for AD compliance (refer to FAA Order 8110.103, Alternative Methods of Compliance (AMOC)).

4.7.2 Use of the 24/7 process is at the discretion of the FAA office responsible for approving AMOCs to the AD. Requests to use the process must come from the Aircraft Evaluation Group after identification of the need for urgent AMOC support by the PI/FSDO/CHDO/IFO.

4.8 Sharing AMOCs with Design Approval Holders.

Some DAHs keep a database of global AMOCs that is available to their operators.

The database allows operators to search previously approved global AMOCs that may apply to their aircraft. To assist DAHs in identifying AMOCs that might be candidates for a global AMOC, requesters may provide consent in the AMOC proposal letter to permit the responsible office to share the AMOC approval response with the DAH.

The responsible office will share with the DAH all AMOC approval responses for proposals that include such consent. The consent must include a statement allowing the FAA to provide the AMOC approval response to the DAH for consideration for a global AMOC.

Example: Operator XYZ grants the FAA approving office permission to share the AMOC approval response with the DAH for their consideration in proposing a global AMOC.

4.9 AMOCs for Appliances Including TSO-Approved Articles.

The FAA has the authority to issue ADs that apply to appliances, including articles approved via TSO authorization (TSOA). As with any other AD, the responsible

4-5 office has the authority to approve AMOCs for an appliance AD. However, there are certain considerations that must be made for this type of AMOC.

4.9.1 Any person, including the TSOA holder, may propose an AMOC for a design change to a TSO article. For more information regarding changes to TSOA articles, refer to FAA Order 8150.1, Technical Standard Order Program.

4.9.2 The design change holder must indicate whether the requested AMOC proposal includes installation approval for the modified TSO article or whether additional approval is required.

4.9.3 The installer of a TSO article modified with an approved AMOC does not require a separate AMOC for the installation of that article.

4.10 AMOCs for Rotable or Unserialized Parts.

When proposing an AMOC that affects a rotable or unserialized part, be sure to carefully check the applicability statement required by paragraph 3.2.2 of this AC.

Because the installation of these types of parts may be eligible for multiple serialized products in an operator’s fleet, it may be appropriate to list more than one serial numbered product on the AMOC proposal. Doing so may avoid having to obtain an identical AMOC if that part is installed on a different serial number product.

4.11 Previously Approved AMOCs.

The following are some frequently asked questions regarding previously approved AMOCs:

4.11.1 Question: I have a previously approved AMOC for a different repair method that applies to my aircraft. I was not the original AMOC proposer, but it is transferable.

Do I need to obtain ACO, directorate, or company DER approval before using it on my aircraft?

Answer: No. However, if the AMOC has not yet been accomplished, you are responsible for notifying your PI (or lacking a PI, the manager of the FSDO/CHDO) before you use it.

4.11.2 Question: Can the new owner/operator of my aircraft use my AMOC?

Answer: Only if the AMOC approval identified it as transferable and you make it available to them.

4.11.3 Question: Can other owners/operators use my AMOC?

Answer: Only if their aircraft are identified in your AMOC approval response.

The AMOC can only be used for the specific aircraft, AD, and paragraph(s) cited in the AMOC approval document. The owner/operator must determine that the AMOC applies to their product (that is, to the model and serial number), whether they can meet any restrictions identified, and that they can accomplish the specific instructions

4-6 in the AMOC. They are also responsible for notifying their PI (or lacking a PI, the manager of the FSDO/CHDO) before using the AMOC.

4.11.4 Question: Is there a fee for using AMOCs?

Answer: The FAA does not charge fees to use AMOCs. However, some AMOC holders may charge fees for allowing others to use their AMOC procedures.

4.11.5 Question: Where can I find information about previously approved AMOCs?

Answer: Pursuant to § 39.21, the office listed in the AD can provide information about AMOCs it has previously approved. Information that can be shared includes the name of the AMOC holder, the date the AMOC was approved, applicable make and model, and the AD number and paragraph(s) to which the AMOC applies. The office cannot provide specifics on the technical nature of the AMOC, nor can it provide you with a copy of an AMOC approval letter. If you seek a copy of an AMOC approval letter, you must request it from the AMOC holder.

Appendix A A-1 APPENDIX A. LIST OF ACRONYMS ACRONYM Acronym Meaning 14 CFR Title 14 of the Code of Federal Regulations AC Advisory circular ACO Aircraft Certification Office AD Airworthiness directive AIR Aircraft Certification Service AMOC Alternative method of compliance CHDO Certificate Holding District Office DAH Design approval holder DER Designated engineering representative FAA Federal Aviation Administration FSDO Flight Standards District Office IFO International Field Office MCDA Military Commercial Derivative Aircraft MCO Military Certification Office ODA Organization Designation Authorization PAH Production approval holder PMA Parts manufacturer approval PI Principal inspector RC Required for compliance SB Service bulletin TSO Technical standard order TSOA Technical standard order authorization

Appendix B B-1 APPENDIX B. RELATED FAA PUBLICATIONS B.1 Where to Find Publications.

Publications referenced throughout this document refer to the latest revision level.

You can get copies from the FAA website at http://www.faa.gov and our Regulatory and Guidance Library (RGL) at http://rgl.faa.gov.

B.2 FAA ACs.

 AC 39-9, Airworthiness Directives Management Process.

B.3 FAA Orders.

 FAA Order 8100.15, Organization Designation Authorization Procedures.

 FAA Order 8110.37, Designated Engineering Representative (DER) Handbook.

 FAA Order 8110.101, Type Certification Procedures for Military Commercial Derivative Aircraft.

 FAA Order 8110.103, Alternative Methods of Compliance (AMOC).

 FAA Order 8150.1, Technical Standard Order Program.

B.4 FAA Manuals.

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