M.A.504
M.A.504(a) Unserviceable and unsalvageable components
(a) Unserviceable and unsalvageable components shall be segregated from serviceable components, standards parts and materials.
M.A.504(b) Unsalvageable components
(b) Unsalvageable components shall not be permitted to re-enter the component supply system unless the mandatory life limitation has been extended or a repair solution has been approved in accordance with Regulation (EU) No 748/2012.
AMC1 M.A.504 Responsibilities- segregation of components
(a) Unserviceable components should be identified and stored in a separate secure location that is managed by the maintenance organisation until a decision is made on the future status of such components. Certifying staff outside maintenance organisations (M.A.801(b)(1), or M.A.801(c)) that release aircraft maintenance should send, with the agreement of the aircraft owner/lessee, any unserviceable component to a maintenance organisation for controlled storage. Nevertheless, the person or organisation that declared the component unserviceable may transfer its custody, after identifying it as unserviceable, to the aircraft owner/lessee provided that such transfer is reflected in the aircraft logbook, or engine logbook, or component logbook.
(b) ‘Secure location under the control of an approved maintenance organisation’ refers to a location that is managed by the approved maintenance organisation that prevents the component from being reused or tampered with. This may include facilities that are established by the organisation at locations different from the main maintenance facilities. These locations should be identified in the relevant procedures of the organisation.
(c) In the case of unsalvageable components, the person or organisation should:
(1) retain such components in the secure location referred to in paragraph (b);
(2) arrange for the component to be mutilated in a manner that ensures that it is cannot be restored for use, before disposing it; or
(3) mark the component indicating that it is unsalvageable, when, in agreement with the component owner, the component is disposed of for legitimate non-flight uses (such as training and education aids, research and development), or for non-aviation applications, mutilation is often not appropriate. Alternatively to marking, the original part number or data plate information can be removed, or a record kept of the disposal of the component for legitimate non-flight uses.
GM1 M.A.504 Mutilation of components
(a) Mutilation should be accomplished in such a manner that the components become permanently unusable for their originally intended use. Mutilated components should not be able to be reworked or camouflaged to provide the appearance of being serviceable, such as by replating, shortening and rethreading long bolts, welding, straightening, machining, cleaning, polishing, or repainting.
(b) Mutilation may be accomplished by one or a combination of the following procedures:
(1) grinding;
(2) burning;
(3) removal of a major lug or other integral feature;
(4) permanent distortion of parts;
(5) cutting a hole with cutting torch or saw;
(6) melting;
(7) sawing into many small pieces; and
(8) any other method accepted by the competent authority.
(c) The following procedures are examples of mutilation that are often less successful because they may not be consistently effective:
(1) stamping or vibro-etching;
(2) spraying with paint;
(3) small distortions, incisions, or hammer marks;
(4) identification by tags or markings;
(5) drilling small holes; and
(6) sawing in two pieces only.