题目内容
（请给出正确答案）
[单选题]
In what cases flights can’t take off on time？
A.登机口变更
B.航班延误
C.航班取消
D.正常登机
提问人：网友flyxisi
发布时间：2022-01-07
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【填空题】Lesson 5 听力填空-1 What is AIr Traffic Control 1. Listening to the recording and answer the following questions: (自己口头回答，不用写答案） Question One : What services does air traffic control provide？ Question Two: What kinds of separation are applied by ATC？ Question Three: Who has the final responsibility for flight safety？ Question Four : Can the flight crew deviate from ATC instructions？ 2. Listening to the recording again and fill in the blanks with words you have heard: Air traffic control is a service provided by ground-based controllers for the aircraft on the ground and in the air. It has three primary purposes: first, to separate aircraft to 1 ; second, to organize and 2 the flow of traffic; third, to 3 and other support for pilots when able. Preventing collisions is referred to as separation. Separation is a term used to prevent aircraft from coming too close to each other by use of 4 vertical and 5 separation minima. Many aircraft now have 6 systems installed to act as a backup to ATC observation and instructions. Aircraft may fly with or without the use of the air traffic control system. If with, the airspace they fly within is called " 7 "airspace, if without, then “ 8 ”airspace. ATC may 9 that pilots are required to follow, or advisories to 10 pilots operating in the airspace. In all cases, however, the pilot in command has 11 for the safety of the flight, and may 12 from ATC instructions in an emergency.
