Direct Answer — AD Alternative Method of Compliance
An Alternative Method of Compliance (AMOC) is an FAA-approved way to address an airworthiness directive's unsafe condition that differs from the method written into the AD. Under 14 CFR §39.19, anyone may propose an AMOC — or a change in the compliance time — if it provides an acceptable level of safety; the proposal goes to your principal inspector, who forwards it to the manager of the office identified in the AD (or you send it directly to that manager if you have no principal inspector), and you may use the alternative only if the manager approves it. 14 CFR §39.17 forces you into that same process whenever a change in the product — a modification, an STC, a repair, a parts substitution — affects your ability to accomplish the AD's required actions. The request alone changes nothing: until the written approval exists, the only lawful method is the one printed in the AD, and operating out of compliance violates §39.7. The records that prove AMOC compliance are the §43.9 maintenance entry plus the AMOC approval document, with the AMOC recorded as the method of compliance in the permanent §91.417(a)(2)(v) AD status record.
A pending AMOC request is not a deadline extension
Under 14 CFR §39.9, you violate §39.7 each time you operate the aircraft when the AD requirements have not been met. §39.19 permits a proposal to change the compliance time, but you may use that revised time only after the manager approves it. Submitting an AMOC request does not authorize flying past an AD deadline.
What an AMOC Is — and What It Is Not
An airworthiness directive exists because the FAA found, under 14 CFR §39.5, that an unsafe condition exists in a product and is likely to exist or develop in other products of the same type design. The AD then specifies the inspections, conditions and limitations, and corrective actions you must take to resolve that unsafe condition. The directive usually prescribes a specific way to do that — replace a part, inspect on an interval, apply a service bulletin. An AMOC is the formal channel for addressing the same unsafe condition by a different means that the FAA agrees provides an acceptable level of safety.
14 CFR §39.19 opens the door and immediately sets the limit. Anyone may propose to the FAA an alternative method of compliance, or a change in the compliance time, if the proposal provides an acceptable level of safety. But the section closes with the operative constraint: you may use the alternative you propose only if the manager of the responsible office approves it. An AMOC is therefore best understood as a conditional permission that does not exist until it is granted in writing. It is not a waiver of the AD, not a blanket exemption, and not something a mechanic, an owner, or even a repair station can self-certify.
An AMOC is
- A different method of addressing the AD's unsafe condition, approved in writing by the FAA
- Potentially a change in the compliance time, if the manager approves it
- Proposable by anyone — owner, operator, repair station, manufacturer
- Routed through your principal inspector to the responsible office's manager
- A document that must be retained with the aircraft records
An AMOC is not
- A waiver or exemption from the AD
- Self-executing — the request does not authorize anything on its own
- A judgment call a mechanic can make in the field without FAA approval
- A license to fly past an AD deadline while approval is pending
- Valid without the written approval document on file
Primary regulations cited in this section: 14 CFR §39.5 (When FAA issues ADs), §39.11 (What actions ADs require), §39.19 (Alternative methods of compliance).
This page is the AMOC-mechanism companion to our guide on documenting AD compliance so it survives a ramp check — which covers the exact logbook wording, recurring next-due math, and §91.417 retention chain for ordinary AD compliance. Read that one first if you need the AD-records fundamentals; read this one for the additional discipline an AMOC requires.
When §39.17 Forces You Into the AMOC Process
14 CFR §39.17 answers the question "What must I do if a change in a product affects my ability to accomplish the actions required in an airworthiness directive?" The rule: if a change in a product affects your ability to accomplish the AD's required actions in any way, you must request FAA approval of an alternative method of compliance. Unless you can show the change eliminated the unsafe condition, your request should include the specific actions you propose to address the unsafe condition, and you submit it in the manner described in §39.19. The key trigger is a product change that collides with an AD's written steps.
A supplemental type certificate (STC) changes the affected area
An STC installation is a major alteration recorded on FAA Form 337. If the STC modifies, replaces, or relocates the component an AD targets, the AD's literal instructions may no longer map to the as-modified configuration. §39.17 directs you to request an AMOC rather than improvise a close-enough accomplishment. The Form 337 documenting the alteration and the resulting AMOC approval should be cross-referenced in the records so the configuration change and its AD consequence are traceable together.
A repair or parts substitution alters the AD-affected part
A repair, a different approved part, or a configuration deviation can change whether or how an AD step is physically possible. If the change affects your ability to accomplish the AD in any way, §39.17 applies. The exception is narrow: you do not need an AMOC if you can show the change eliminated the unsafe condition — and "show" means evidence the FAA accepts, documented in the records, not an assumption.
The compliance time itself needs to move
Separately from a product change, §39.19 lets anyone propose a change in the compliance time if it provides an acceptable level of safety. This is still an AMOC — it follows the same routing and the same approval gate. A revised interval or deadline becomes effective only on the manager's written approval, and the approved revised time then becomes the figure you track in the §91.417(a)(2)(v) status record for that AD.
"The change eliminated the unsafe condition" is an evidence claim, not a convenience
§39.17 relieves you of the AMOC request only if you can show the change eliminated the unsafe condition. That is a substantiation burden carried in the records — typically an engineering determination acceptable to the FAA — not a field judgment. If you cannot document why the unsafe condition no longer applies to your aircraft, the AD still applies and the §39.19 process is the path.
Because an STC installation is a major alteration, the configuration record matters as much as the AD record here. See our guides on the FAA Form 337 major repair and alteration record and the major-versus-minor repair/alteration determination for how a configuration change is documented before it ever reaches an AD question.
Not sure whether a modification on your aircraft has opened an AD question you never closed? A records snapshot is the fastest way to surface it.
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The §39.19 Approval Routing — Who Decides, and How
14 CFR §39.19 describes the path precisely. Unless the FAA authorizes otherwise, you send your proposal to your principal inspector; the principal inspector may add comments and will send your request to the manager of the office identified in the AD. You may send a copy to the manager at the same time. If you do not have a principal inspector, you send your proposal directly to the manager. And the proposal must include the specific actions you are proposing to address the unsafe condition. The approval authority is the manager of the responsible office — not the inspector, not the operator, not the repair station.
Step-by-Step: From Proposal to Approved AMOC
- 1
Identify the responsible office named in the AD
Every AD identifies the office responsible for approving alternative methods of compliance. Per §39.21, that office can also tell you about AMOCs it has already approved — start there before drafting a fresh proposal.
- 2
Document the proposed alternative and why it is safe
The proposal must include the specific actions you propose to address the unsafe condition and must support an acceptable level of safety. This is the substantive engineering case — usually prepared by or with the design-approval holder, a DER/ODA, or the manufacturer — and it is the foundation of the record.
- 3
Submit through your principal inspector (or directly to the manager)
Send the proposal to your principal inspector, who may add comments and forwards it to the manager of the identified office. You may copy the manager simultaneously. If you have no principal inspector, send it directly to the manager.
- 4
Wait for written approval before using the alternative
You may use the alternative you propose only if the manager approves it. Until that written approval is in hand, comply by the method printed in the AD — or, if you cannot, do not operate the aircraft (see §39.7 and §39.9).
- 5
File the approval with the aircraft records and reference it at every compliance event
The AMOC approval document becomes the method of compliance recorded under §91.417(a)(2)(v). Each §43.9 entry that relies on the AMOC must identify it, and the approval document must stay with the records for as long as compliance under that AD rests on it.
Finding an existing AMOC — §39.21
14 CFR §39.21 answers "Where can I get information about FAA-approved alternative methods of compliance?" Each AD identifies the office responsible for approving AMOCs, and that office can provide information about alternatives it has already approved. Sometimes the FAA issues a broadly applicable ("global") AMOC; sometimes an AMOC is specific to one aircraft and serial number.
The records discipline is the same either way: confirm in writing that the existing AMOC applies to your specific aircraft and configuration, and keep that confirmation with the AD status record. An AMOC approved for a different operator or a different configuration does not automatically cover yours.
Repositioning the aircraft to do the work — §39.23
If the aircraft is out of compliance and must be flown to a facility to accomplish the AD work (by the printed method or an approved AMOC), 14 CFR §39.23 governs the movement. Some operators hold operations specifications authority that includes a provision to fly to a repair facility for AD work; operators without it may be issued a special flight permit by the local Flight Standards District Office unless the AD states otherwise. The FAA may attach special requirements or decline the permit if the aircraft cannot be moved safely.
The permit or OpSpec authority, and any conditions on it, belong in the records for that flight. See our special flight permit / ferry permit records guide for how that authorization is documented — and remember a permit authorizes the flight, not AD compliance.
For the broader maintenance-entry rules that govern the record an A&P or repair station makes when accomplishing AMOC work, see the 14 CFR §43.9 maintenance record entry guide and, for the inspection schedule that surfaces open ADs, the 14 CFR §91.409 annual inspection requirements.
The AMOC Records — §43.9 Entry + Approval Document + §91.417 Status
AMOC compliance is documented like ordinary AD compliance, plus one dependency that creates its own failure points. The two core records are the maintenance entry and the permanent AD status line; the AMOC adds the requirement that a separate FAA approval document exists and remains findable.
Complied with Airworthiness Directive AD [year-week-seq] using FAA-approved Alternative Method of Compliance (AMOC) per [responsible office], AMOC reference [number/letter], dated [date]. AMOC approval document on file with aircraft records. [Recurring AMOC interval, if any.] Airframe total time: [hours]. [Date]. [A&P name]. Certificate No. [number], [kind of certificate]. [Signature].
- Names the AD by full designation — so an inspector can pull the FAA AD record and confirm applicability
- States that compliance was by an FAA-approved AMOC and identifies the AMOC reference and date
- Notes that the AMOC approval document is on file — pointing to the supporting record
- Per §43.9(a): description of work, date of completion, performer name, and the approver's signature, certificate number, and kind of certificate
Example entry format for illustration only — exact wording, applicable paragraphs, and the kind of certificate held depend on the AD, the AMOC, and the person approving return to service. The AD designation shown in brackets is a placeholder, not a real AD.
14 CFR §91.417(a)(2)(v) requires the permanent record to show, for each applicable AD, the current status including the method of compliance, the AD number and revision date, and — if the AD involves recurring action — the time and date when the next action is required. When compliance was by AMOC, the method of compliance recorded there is the AMOC (identified by its reference and date), not the AD's printed method.
- Method of compliance field reads "AMOC [reference], dated [date]" rather than a paragraph or service-bulletin number
- AD number and revision date still recorded exactly as for any AD
- For a recurring AMOC, the next-due time and date reflect the AMOC's interval — which may differ from the base AD interval
- Under §91.417, this status record is retained and transferred with the aircraft when it is sold
The §43.9 entry and the §91.417 status line both reference the AMOC. The AMOC approval document itself — the written approval from the responsible office — is a separate record that must travel with the aircraft and be presented to any inspector reviewing that AD. Without it, the entry that relies on it has no evidentiary support: an inspector who cannot locate the AMOC approval is, in practice, looking at an unsupported compliance claim.
This is the single most common AMOC-specific records failure. The maintenance got done correctly and the entry was made — but the approval letter was filed in a project folder, a shop's STC package, or an email thread, and never made it into the permanent aircraft records that transfer at sale. Keep the approval indexed to the AD it modifies.
AMOC at Aircraft Sale — the Chain Has to Transfer
Under 14 CFR §91.403(a), the owner or operator is primarily responsible for maintaining the aircraft in airworthy condition, including compliance with part 39. When an aircraft changes hands, the AMOC approval documents are part of what makes the AD status record meaningful — a status line that says "complied via AMOC" is only as good as the approval behind it. A buyer who accepts an aircraft whose status record references AMOCs should verify each referenced approval is physically in the records, applies to this aircraft, and matches the as-flown configuration. A missing AMOC approval can turn an apparently compliant AD into an undocumented one the new owner must re-establish.
The risk concentrates where AMOCs intersect with configuration changes — STCs, repairs, parts substitutions that triggered §39.17 in the first place. A pre-purchase records review by an IA should specifically reconcile the configuration record (the Form 337s and ARROW documents) against the AD status record, so any AMOC driven by a modification is accounted for.
FileFlo as the AMOC Records Layer
FileFlo is a compliance document intelligence platform — a read-only proof layer that sits alongside your maintenance tracking stack. It does not approve AMOCs, perform maintenance, hold your certificate, or replace your CAMP, your IA, or your A&P's work-order system. What it does is keep the documents that prove AMOC-based AD compliance findable when an inspector — or a buyer — asks.
- Classifies uploaded AMOC approval documents and links them to the AD they modify, so the approval is never orphaned from its compliance entry
- Classifies the §43.9 entry and the §91.417 status record against the governing 14 CFR reference (§39.19, §39.17, the specific AD)
- Tracks next-due dates for recurring AMOCs separately from the base AD interval, with expiration alerts at 90/60/30 days
- Surfaces the configuration record (Form 337, STC paperwork) alongside any AMOC the change triggered under §39.17
- Generates an inspector-format AD-and-AMOC status binder on demand — each AD with its method of compliance, the AMOC reference, and the supporting approval visible together
FileFlo classifies 600+ aviation document types and manages records across Part 91, Part 135, and Part 145 operators in a single platform. Pricing: Starter $89/mo, Professional $299/mo. 5-day free trial, no credit card required. FileFlo does not provide or run a safety management system, dispatch system, or flight operations system — it keeps the documents that prove compliance audit-ready.
Who Carries the AMOC Records — Part 91, Part 135, Part 145
The AMOC mechanism in §39.19 is the same for every operator of a US-registered aircraft, because the underlying duty in §39.7 is universal and §39.13 makes ADs part of the CFR. What differs is who owns the records function and who routes the proposal.
Who is responsible
Owner/operator (§91.403)
Owner is personally responsible for the AMOC request and for keeping the approval document with the records. Often the most exposed to a missing-approval gap on a sold aircraft.
Who is responsible
Director of Maintenance via OpSpecs
The DOM typically owns AD/AMOC tracking under the approved maintenance program; the Principal Maintenance Inspector is the usual routing point for the §39.19 proposal.
Who is responsible
Repair station (entry) + operator (retention)
A repair station accomplishing AMOC work makes the §43.9 entry; the operator retains the §91.417 status record and the AMOC approval. Both sides must keep the chain intact.
For the operator-side records picture, see what records a Part 135 operator must keep and Part 91 aircraft records requirements. For the repair-station side that produces and retains the maintenance record of an AMOC accomplishment, see Part 145 repair station recordkeeping requirements and the Part 145 audit binder inspectors ask for.
AD and AMOC status is also a standard line item in a Part 135 surveillance review. Our guides on preparing for a Part 135 FAA surveillance audit and the Part 135 CAMP maintenance recordkeeping requirements put AMOC documentation in the context of a full records review.
Frequently Asked Questions
What is an Alternative Method of Compliance (AMOC) under 14 CFR §39.19?
An AMOC is an FAA-approved way of addressing the unsafe condition that differs from the corrective action written into the body of the airworthiness directive. 14 CFR §39.19 is titled "May I address the unsafe condition in a way other than that set out in the airworthiness directive?" and answers yes — anyone may propose to the FAA an alternative method of compliance, or a change in the compliance time, if the proposal provides an acceptable level of safety. The section is specific about routing: unless the FAA authorizes otherwise, you send the proposal to your principal inspector, who may add comments and forwards it to the manager of the office identified in the AD; if you have no principal inspector, you send it directly to that manager. The decisive sentence is the last one: you may use the alternative you propose only if the manager approves it. Until that written approval exists, the only lawful way to comply is the method printed in the AD itself.
Does an AMOC let me skip an airworthiness directive or extend a deadline on my own?
No. An AMOC is not a waiver and it is not self-executing. 14 CFR §39.7 states that anyone who operates a product that does not meet the requirements of an applicable airworthiness directive is in violation of that section, and §39.9 adds that you violate §39.7 each time you operate the aircraft or use the product when the AD requirements have not been met. §39.19 does allow a proposal for a change in the compliance time, but the same approval gate applies — you may use the alternative (including a revised compliance time) only after the manager of the responsible office approves it. Flying past an AD deadline on the assumption that an AMOC request is pending, or treating your own engineering judgment as an AMOC, is operating out of compliance. The written AMOC approval is what changes your obligation; the request alone changes nothing.
What record proves AMOC-based AD compliance to an inspector?
Two records together. First, the maintenance entry made under 14 CFR §43.9(a) — a description of the work performed, the date of completion, the name of the person who performed the work (if different from the approver), and the signature, certificate number, and kind of certificate of the person approving the work for return to service. Best practice is to name the AD by its full designation and state that compliance was accomplished per the FAA-approved AMOC, identifying the AMOC approval by its reference and date. Second, the AMOC approval document itself — the written approval from the responsible office — retained with the aircraft records. 14 CFR §91.417(a)(2)(v) requires the permanent AD status record to show, for each applicable AD, the method of compliance, the AD number and revision date, and for recurring action the time and date when the next action is required. The method of compliance recorded there is the AMOC. An entry that references an AMOC the inspector cannot locate is, in practice, an unsupported entry.
What does 14 CFR §39.17 require when a product change affects AD compliance?
Section 39.17 is titled "What must I do if a change in a product affects my ability to accomplish the actions required in an airworthiness directive?" It provides that if a change in a product affects your ability to accomplish the actions required by the AD in any way, you must request FAA approval of an alternative method of compliance. Unless you can show the change eliminated the unsafe condition, your request should include the specific actions you propose to address the unsafe condition, and you submit it in the manner described in §39.19. In plain terms: when a modification, a supplemental type certificate installation, a repair, or a parts substitution makes the AD's written steps no longer fit your aircraft, you cannot quietly do something close to the AD and move on — you go through the §39.19 AMOC process. From a records standpoint, the change that triggered §39.17 and the resulting AMOC approval both belong in the aircraft records so a future reader can see why the as-flown configuration differs from the literal AD text.
Where do I find AMOCs that the FAA has already approved for an AD?
Each airworthiness directive identifies the office responsible for approving alternative methods of compliance. 14 CFR §39.21 is titled "Where can I get information about FAA-approved alternative methods of compliance?" and states that the office identified in the AD can provide information about alternatives it has already approved. Global AMOCs (approvals the FAA intends to apply to an entire fleet or model, rather than to one aircraft) are sometimes published or referenced in the AD or in subsequent FAA correspondence. The practical workflow is to read the AD's AMOC paragraph, note the responsible office, and contact that office — or your principal inspector — before assuming an existing AMOC covers your situation. Even when a previously approved AMOC appears to apply, the safe records practice is to confirm in writing that it applies to your specific aircraft and to keep that confirmation with the AD status record.
Can I fly the aircraft to a shop to accomplish AD work, or to use an AMOC?
Possibly, but only under a specific authority — flying an out-of-compliance aircraft is otherwise prohibited by §39.7. 14 CFR §39.23 is titled "May I fly my aircraft to a repair facility to do the work required by an airworthiness directive?" It explains that some operators hold operations specifications authority that includes a provision allowing them to fly the aircraft to a repair facility to do the work required by an AD; if you do not have that authority, the local FAA Flight Standards District Office may issue a special flight permit unless the AD states otherwise. The FAA may add special requirements for the flight and may decline to issue a permit if the aircraft cannot be moved safely. The permit or the OpSpec authority, plus any conditions attached to it, should be retained with the records for that movement. A special flight permit is not AD compliance — it is temporary authorization to reposition the aircraft so compliance (whether by the AD method or an approved AMOC) can be accomplished.
Who is responsible for AD and AMOC compliance, and what are the penalties for getting it wrong?
Under 14 CFR §91.403(a), the owner or operator of an aircraft is primarily responsible for maintaining that aircraft in an airworthy condition, including compliance with part 39 of the chapter — which is the airworthiness directives part. ADs apply because of the unsafe-condition findings described in §39.5 (an unsafe condition exists in the product and is likely to exist or develop in other products of the same type design), and §39.13 confirms ADs are part of the Code of Federal Regulations even though they are published in the Federal Register rather than codified in the annual edition. If an aircraft is operated without the AD complied with — by the printed method or an approved AMOC — §39.7 is violated each flight under §39.9, and civil penalties under 49 U.S.C. §46301 apply. As reflected in 14 CFR §13.301, for a violation occurring on or after December 30, 2024, the maximum civil penalty is $75,000 for a person other than an individual or small business concern, and $1,875 for an individual or small business concern. The records are what stand between "we complied via an approved AMOC" and "we cannot prove it."
How is documenting an AMOC different from documenting ordinary AD compliance?
Ordinary AD compliance is documented by naming the AD and the paragraph or service-document method used, plus the §43.9 entry and the §91.417(a)(2)(v) status line. AMOC compliance adds a dependency: the entry relies on a separate FAA approval document that must exist, must be findable, and must remain with the aircraft for as long as compliance under that AD rests on it. There are three extra failure points compared with a normal AD: the AMOC approval letter can go missing, the entry can fail to identify which AMOC was used, and a recurring AMOC can carry its own interval or terms that differ from the base AD and must be tracked separately. For the underlying AD compliance mechanics — exact logbook wording, recurring next-due math, and retention — see our companion guide on documenting AD compliance so it survives a ramp check. This page focuses specifically on the §39.17 and §39.19 AMOC mechanism and the additional records it creates.
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Written by Chad Griffith, Founder, FileFlo — compliance document intelligence. Reviewed June 13, 2026. FileFlo is a compliance document intelligence platform — not legal counsel, an A&P, or the FAA. AMOC approval, AD applicability, and acceptable compliance methods must be confirmed with a certificated A&P or IA and with the FAA office identified in the specific AD.