23Conversely, it is clear from the Court’s case-law that the premature failure of certain parts of an aircraft does not constitute extraordinary circumstances, since such a breakdown remains intrinsically linked to the operating system of the aircraft. That unexpected event is not outside the actual control of the air carrier, since it is required to ensure the maintenance and proper functioning of the aircraft it operates for the purposes of its business (see, to that effect, judgment of 17 September 2015, van der Lans, C‑257/14, EU:C:2015:618, paragraphs 41 and 43).