Singapore legislation
Regulation 48
of Air Navigation (91 — General Operating Rules) Regulations 2018
Regulation 48
Reporting of weather and hazardous conditions
Subregulation 1
The pilot-in-command of a relevant aircraft must make a report to the appropriate aeronautical station as soon as possible when any of the following conditions are encountered or observed during flight:
moderate or severe turbulence;
moderate or severe icing;
severe mountain wave;
thunderstorm (with or without hail), that are obscured, embedded, widespread or in squall lines;
heavy duststorm or heavy sandstorm;
volcanic ash cloud;
pre‑eruption volcanic activity or a volcanic eruption;
any hazardous conditions other than those associated with meteorological conditions, that in the pilot‑in‑command’s opinion is likely to affect the safety of other aircraft.
Subregulation 2
The report made under paragraph (1) must provide such details as may be pertinent to the safety of other aircraft.