Aircraft Flight Operation Regulations Article 85
Performance class 3 helicopters shall only be operated in conditions of weather or illumination, and over such routes and diversions there from, that permit a safe forced landing to be executed in the event of engine failure.The conditions in the preceding paragraph apply also to performance class 2 helicopters prior to the take off critical point after take-off and after the landing critical point before landing.
中文原文 航空器飛航作業管理規則第85條
三級性能直昇機為確保動力機件失效時能安全執行迫降，僅得於航路及轉降航路上之天氣或照明條件許可下飛航。
前項於二級性能直昇機在起飛臨界點前及降落臨界點後亦適用之。
前項於二級性能直昇機在起飛臨界點前及降落臨界點後亦適用之。