Rules of the Air Article 70
Aircraft operated as an IFR flight shall be equipped with suitable instruments and navigation equipment appropriate to the route to be flown.
中文原文 飛航規則第70條
實施儀器飛航之航空器應備有適當之儀器及適合所飛航線之航行裝備。
English translation for reference only; the Chinese text prevails. Not legal advice.