第四章 空中交通管理 第五节空域管理和流量管理 Control zones class ‘D’: Control areas class ’D’: separation IFR and VFR flights Air traffic control service provided to IFR and VFR flights traffic information IFR flights received traffic information in respect of VFR flights traffic information VFR flights received traffic information in respect of all other flights 空域管理 空中交通流量管理 Over 5,000 aircraft operating at the same time in the U.S. 空中交通流量管理 capacity Initial demand capacity Regulated demand Overload !