Singapore legislation
Regulation 137
of Air Navigation (121 — Commercial Air Transport by Large Aeroplanes) Regulations 2018
Regulation 137
Flight crew operating limitations
Subregulation 1
An AOC holder must specify in its Operations Manual any flight crew operating limitations for a flight crew member on a large aeroplane.
Subregulation 2
Unless otherwise approved by the Director‑General of Civil Aviation under the Air Navigation (98 — Special Operations) Regulations 2018, an AOC holder must ensure that every person who may be assigned duty in the following flight crew member roles is assigned to that role in only one aircraft type or, where there are significant differences between variants of a type, one variant:
a pilot, not being a pilot who may be assigned to a Mixed Fleet Flying operation in accordance with the Air Navigation (98 — Special Operations) Regulations 2018;
a flight engineer.