21L.A.221 Scope

Manuals and other instructions for continued airworthiness (such as the manufacturer’s structural repair manual, maintenance manuals and engine manuals provided by the declarant for a declaration of design compliance) for operators contain useful information for the development and approval of repairs. When that data is explicitly identified as being declared applicable for use, it may be used by operators without further actions to cope with anticipated in-service problems arising from normal usage provided that it is used strictly for the purpose for which it has been developed. Declared design data is data which is declared as being applicable for use by the declarant of a declaration of design compliance. Approved data is data which is approved by an appropriately approved design organisation.