If you wish to contribute or participate in the discussions about articles you are invited to join SKYbrary as a registered user
From SKYbrary Wiki
Airworthiness Directives (ADs) form part of the ongoing obligations of aircraft certification authorities under Part-21 with regard to the continuing airworthiness of aircraft. They address recommendations for improvements or corrective actions to be implemented by the holder of the Certificate of Airworthiness. The issue of an AD has the effect of making such recommendations mandatory.
The ADs contain mandatory instructions to carry out work on aircraft, engine, propeller or component in order to address an unsafe condition which exists, or is likely to exist, or could develop. It may be issued by any NAA which has responsibility for the regulation of design of those aircraft or components. It is usual for an NAA to require compliance with an AD issued by another NAA with such responsibility where such aircraft are operated by or maintained by regulated organisations within its jurisdiction.
In Europe, ADs are issued by the European Aviation Safety Agency (EASA) acting in accordance with Regulation (EC) No 216/2008 on behalf of the European Community, its Member States and of the European third countries that participate in the activities of EASA under Article 66 of that Regulation. The criteria for issuance of an AD are defined in 21A.3B and associated AMC material.
For products, parts and appliances, for which the Agency only exercises the design responsibilities of the State of Registry, its policy is to endorse automatically the airworthiness directives issued by the State of Design, except if it itself issues a different airworthiness directive before the date that the AD of the State of design takes effect.
EASA can adopt ADs from countries outside the coverage of the EASA Regulation arrangements. Any AD issued by the State of Design for an aircraft imported from a third country, or for an engine, propeller, part or appliance imported from a third country and installed on an aircraft registered in a EU Member State, shall apply unless EASA has issued a different decision before the date of entry into force of that AD.
In accordance with Regulation EC 2042/2003 Annex I, Part M.A.301, the continuing airworthiness of an aircraft shall be ensured by accomplishing any applicable ADs. Consequently, no person may operate an aircraft to which an AD applies, except in accordance with the requirements of that AD unless otherwise specified by the EASA [EC 2042/2003 Annex I, Part M.A.303] or agreed with the Authority of the State of Registry [EC 216/2008, Article 14(4) exemption].
ADs applicable to an EASA-approved type certificate are those ADs which have been issued or adopted by EASA.
The dissemination of airworthiness directives to aircraft owners is a responsibility of the State of Registry and does not belong to the Agency.
EASA publishes a complete list of ADs that have been issued by EASA or have received an EASA approval number since 28 September 2003. The EASA publication also contains all Proposed Airworthiness Directives (PAD) and allows for user comments for consultation purposes.
After 15th of September 2008, new Safety Information Bulletins, Foreign State of Design Safety Publications and Foreign State of Design ADs are published.
- Further information on Airworthiness Directives may be found on the EASA website
- See the Airworthiness Directives issued by FAA at: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/MainFrame?OpenFrameSet
- AAIB Safety Study - 1/2016: Airworthiness of Aircraft Registered Overseas and Resident in the UK, published January 2016.