Occupation of seats and wearing of restraints
59.—(1)  For every flight of a large aeroplane, the AOC holder must ensure that —
(a)every person on board the aeroplane is seated and restrained in accordance with regulation 51 of the Air Navigation (91 — General Operating Rules) Regulations 2018; and
(b)if cabin crew is required in accordance with regulation 138 —
(i)every person assigned as a cabin crew member for the flight is seated with the person’s seat belt, or safety harness when provided, fastened during take‑off, landing and such other times as the pilot‑in‑command may require; and
(ii)any cabin crew member assigned to emergency evacuation duties occupies a cabin crew seat during take‑off, landing and such other times as the pilot‑in‑command may direct.
(2)  An AOC holder must not permit a cabin crew seat in a large aeroplane to be occupied by a person other than a cabin crew member unless the aeroplane is landing in the following circumstances:
(a)where unexpected crew incapacitation results in an insufficient number of cabin crew members who are able to operate the emergency exits;
(b)where an emergency is declared and the person is displaced from a passenger seat to a cabin crew seat to enhance evacuation management.
(3)  An AOC holder must ensure that a person who is not a cabin crew member does not occupy a cabin crew seat in the circumstances described in paragraph (2)(a) or (b) unless —
(a)the person is able-bodied and was briefed on the necessary safety procedures, including the activation of the exit door, before being permitted to occupy the cabin crew seat and to assist in evacuation management; and
(b)the AOC holder has established relevant procedures in its Operations Manual.
(4)  In this regulation, “cabin crew seat” means a seat provided in accordance with regulation 87(4).