Alternative Method of Compliance (AMOC) to an Airworthiness Directive (AD) - FAQ

What is an Alternative Method of Compliance (AMOC) to an Airworthiness Directive (AD)?

An Alternative Method of Compliance (AMOC) is an EASA approved deviation to an AD.
It is a different way, other than the one specified in an AD, to address an unsafe condition on products, parts and appliances. An AMOC must provide a level of safety equivalent to the level of safety to be restored by  compliance with the original AD.
AMOCs may be issued in respect of, but are not necessarily limited to, the following:

  • Alternative modifications,
  • Alternative inspection procedures,
  • Alternative maintenance intervals and/or procedures,
  • Specific operating procedures or limitations, etc.

What is not an Alternative Method of Compliance (AMOC) to an Airworthiness Directive (AD)?

Requests for extension of compliance time without other alternative compliance methods or compensative factors are in general not eligible for an AMOC application. The operator may wish to contact the responsible national authority and apply for a temporary exemption in accordance with Article 14.4 of Regulation (EC) No 216/2008. A justification document from the type certificate holder may be suitable to support such a time limited exemption on a case by case basis.

Why have provisions for the approval of an AMOC with AD?

Provisions for an 'Alternative Method of Compliance with an AD' are desirable from an aircraft operator's and a TC Holder's point of view when acceptable methods are developed for AD compliance if a limited number of aircraft are eligible to these acceptable methods (and no change to the AD is planned) or while awaiting a planned revision or supersedure of an AD.

For which ADs can an AMOC be approved by EASA?

EASA can accept AMOC applications for any AD that has been issued or adopted by EASA, i.e:

  • ADs that EASA has issued and published online in its AD Tool
  • ADs that EASA has approved  and published in its AD Tool (i.e. an AD previously published in the period 2003-2006 by the EU MS NAAs)
  • ADs that EASA has grandfathered, as per Regulation (EC) No 1702/2003, and,
  • ADs that EASA has adopted i.e. Foreign State of Design ADs on non-EU products.

How is an AMOC application request made to EASA?

All applications for 'Request for acceptance of Alternative Methods of Compliance (AMOC) with Airworthiness Directive (AD)' must be submitted to EASA using Form 42 duly completed and signed.
Unsigned applications cannot be accepted. It should also be noted that every AMOC application request should relate to one AD only.

What if an AMOC application is linked to a Minor or Major Design Change or STC application?

The AMOC will be approved after approval of the related Minor or Major Design Change or STC approval.

Does EASA accept AMOC applications concerning aircraft registered in a non-EU Member State?

EASA cannot accept applications for aircraft that are not registered in an EU Member State, or associated country, as this would be outside of its jurisdiction, unless the applicant is an EU TC Holder.
In these situations EASA advises such operators to, either:

  • Contact their local National Aviation Authority (NAA) for assistance, or
  • Contact the European TC holder of the product to which the AD applies for them to send to EASA an AMOC application request, using Form 42.

For EU registered aircraft being non-EU products, does EASA automatically accept AMOCs approved by the State of Design authority?

  • If the State of Design (SoD) is the USA, Canada or Brazil: EASA has three separate ED Decisions where an AMOC approval held by the TC/STC holder of the product to which the AD applies is confirmed as automatically considered approved by EASA. Therefore, no further application to EASA is necessary for European registered aircraft.
  • For all other State of Design countries, or if the AMOC approval is not held by the TC / STC Holder of the product to which the AD applies: an AMOC application must be submitted to EASA using Form 42. The prior issuance of an equivalent AMOC approval by the State of Design authority is recommended and likely to facilitate the EASA AMOC approval process.  Only after EASA approval could such an AMOC be applied to aircraft registered in EU Member States or associated countries (the latter as per Article 66 of the Basic Regulation, Regulation (EC) No 216/2008).

Under which conditions are Federal Aviation Administration (FAA) AMOCs approved?

Please refer to Article 4 of EASA Decision 2004/04/CF of The Executive Director of The Agency of 10 December 2004 on the acceptance of certification findings made by the Federal Aviation Administration (FAA) for products designed in the United States of America and repealing Decision No 2004/01/RM.

Under which conditions are Transport Canada (TCCA) AMOCs approved?

Please refer to Article 4 of EASA Decision 2004/02/CF of The Executive Director of The Agency of 10 December 2004 on the acceptance of certification findings made by Transport Canada, Civil Aviation Department (TCCA) for products designed in Canada.

Under which conditions are DAC/CTA AMOCs approved?

Please refer to article 4 of EASA Decision 2004/03/CF of The Executive Director of The Agency of 10 December 2004 on the acceptance of certification findings made by the 'Departamento de Aviação Civil,' Centro Tecnico Aeroespacial (DAC/CTA) for products designed in Brazil.

What are EASA's Fees & Charges?

The level of fees payable by applicants for certificates and approvals issued, maintained or amended by the Agency, and of charges for publications, handling of appeals, training and any other service provided by the Agency are determined by Commission Regulation (EC) No 593/2007 as amended by Commission Regulation (EC) No 1356/2008.
The treatment of AMOC applications is regarded as a service. Therefore, applicants for 'Alternative Methods of Compliance (AMOC) with an Airworthiness Directive (AD)' will be charged in accordance with the Commission Regulation (EC) No. 593/2007 of 31 May 2007 on the Fees & Charges levied by the European Aviation Safety Agency (OJ L 140, 1 June 2007, p. 3).
According to Articles 10 and 11 of the afore-mentioned Regulation, the services provided by EASA give rise to charges which shall be equal to the real cost of the service provided, including administrative costs. The real costs associated with the service are determined as follows:
1. Hours performed by EASA technical experts and/or the EASA's contractors (NAAs)
2. Travel costs, which are payable by EASA to its contractors or staff, including:

a) Transport costs (airplane ticket, visa costs, train, car, bus, taxi)
b) Travel time costs (travel time x hourly rate)
c) All other costs (accommodation and meals, incidental expenses and travel allowances paid to  staff in the context of those activities).

The applicable hourly rate is defined in Part II of the Annex of the Regulation, currently 230, 40 Euros.
In the event of cancellation of the application, refusal of a quote (provided on request by an applicant) or refusal to issue the approval, the working hours already spent will be fully recovered. EASA will also recover, if applicable, any travel costs.

When will EASA issue the AMOC approval?

Once the technical investigation is completed and the AMOC request thereby approved, EASA will immediately issue the approval, in electronic format and by email, to the applicant.
The original document will follow by (regular) post, sent together with EASA's invoice for the actual number of hours spent on the technical investigation, and addressed to the 'Financial Contact' person designated by the applicant on Form 42.

Are AMOCs published to EASA's web site?

No, EASA provides the AMOC approval only to the applicant (the AMOC approval holder) that has applied for it and, if relevant, to the authority of state of registry (in case of an application coming directly from an operator).
Therefore EASA does not publish AMOCs to its web site, or add the AMOCs to the AD tool - as it does for PADs and ADs.
Where an AMOC to an EASA AD is of generic nature e.g. not limited to a few aircraft, this should lead to a revision of the affected AD. The AD would then be posted to EASA's website and the alternative method of compliance in that way then made public.

The AD has been superseded: Is the related AMOC still valid?

The supersedure of an AD always and automatically invalidates any AMOC related to that AD.
Even though the technical solution as specified in an AMOC may still be acceptable for compliance with the new AD, this acceptability must be confirmed. To achieve this, the AMOC approval holder (if that organisation wishes to remain the responsible approval holder) would need to apply for an AMOC to EASA, using Form 42.
There is no (other) process in existence to 'transfer' an AMOC approval from one AD to another.

The AD has been revised: Is the related AMOC still valid?

The AMOC is still valid, as a revision of an AD cannot introduce more stringent requirements.

Can an application be submitted for an AMOC to a proposed AD (PAD)?

No. AMOC applications to PADs are not accepted. PADs that are published to EASA's website remain open for consultation and comments prior to publication as an (eventual) AD.
Every AMOC application request should relate to one AD only.

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