ED Decision 2003/13/RM
Means must be provided to allow:
(a) inspection of principal structural elements and control systems;
(b) replacement of parts normally requiring replacement; and
(c) adjustment and lubrication as necessary for continued airworthiness.
The means of inspection must be practicable for the inspection intervals established for the item during certification. This must be stated in the maintenance manual required under CS 22.1529.