GM 21.A.431A(e) Repairs to European technical standard order (ETSO) articles other than auxiliary power units (APUs)

• ED Decision 2019/018/R found in: Initial Airworthiness and Environmental Protection (748/2012) Part-21 Part-21L (Jul 2024)

GM 21.A.431A(e) Repairs to European technical standard order (ETSO) articles other than auxiliary power units (APUs) ED Decision 2012/020/R A repair to an ETSO article other than an APU can be either be seen: 1.       Under [21.A.611](#_DxCrossRefBm1649097039) in the context of an ETSO authorisation, i.e., when an article as such is specifically approved under Subpart O, with dedicated rules that give specific rights and obligations to the designer of the article, irrespective of any product type design or change to the type design. For a repair to such an article, irrespective of installation on any aircraft, Subpart O, and [21.A.611](#_DxCrossRefBm1649097039) in particular, should be followed; or 2.       When an airline or a maintenance organisation is designing a new repair (based on data not published in the TC holder or Original Equipment Manufacturer documentation) on an article installed on an aircraft, such a repair can be considered as a repair to the product in which the article is installed, not to the article taken in isolation. Therefore Subpart M can be used for the approval of this repair, that will be identified as ‘repair to product x affecting article y’, but not ‘repair to article y’. ##### GM 21.A.431A(e) Repairs to European technical standard order (ETSO) articles other than auxiliary power units (APUs) *ED Decision 2012/020/R* A repair to an ETSO article other than an APU can be either be seen: 1. Under [21.A.611](#_DxCrossRefBm485230530) in the context of an ETSO authorisation, i.e., when an article as such is specifically approved under Subpart O, with dedicated rules that give specific rights and obligations to the designer of the article, irrespective of any product type design or change to the type design. For a repair to such an article, irrespective of installation on any aircraft, Subpart O, and [21.A.611](#_DxCrossRefBm485230530) in particular, should be followed; or 2. When an airline or a maintenance organisation is designing a new repair (based on data not published in the TC holder or Original Equipment Manufacturer documentation) on an article installed on an aircraft, such a repair can be considered as a repair to the product in which the article is installed, not to the article taken in isolation. Therefore Subpart M can be used for the approval of this repair, that will be identified as ‘repair to product x affecting article y’, but not ‘repair to article y’.