Rules of the Air Article 49
An aircraft operated as a controlled flight shall maintain continuous air-ground voice communication watch on the appropriate communication channel of, and establish two-way communication as necessary with, the appropriate ATC unit, except as may be prescribed by the appropriate ATS authority in respect of aircraft operating in the manoeuvring area or in the vicinity of a controlled aerodrome.
中文原文 飛航規則第49條
除適當飛航服務主管機關對管制機場操作區內活動及機場附近飛航之航空器另有規定外，管制飛航之航空器應守聽航管單位適當之陸空語音無線電頻率，並視需要建立雙向通信。