Method of carriage of persons
12.—(1)  A relevant operator must ensure that, when a relevant aircraft is in flight, no person is carried in or on any part of the aircraft which was not designed for the accommodation of persons.
(2)  A relevant operator must not carry any person in or on any object, other than a glider or flying machine, towed by or attached to a relevant aircraft that is in flight.
(3)  Despite paragraphs (1) and (2), a relevant operator may allow a person to have temporary access to any part of a relevant aircraft when the aircraft is in flight —
(a)to take any action necessary for the safety of the aircraft, or the safety of any person or cargo in the aircraft; or
(b)if the part of the aircraft where cargo or stores are carried is designed to enable a person to have access while the aircraft is in flight, to access the cargo or stores carried.