题目内容
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提问人：网友zhenghua809
发布时间：2022-01-06
[主观题]
A．designB．designingC．designedD．designs
A．design
B．designing
C．designed
D．designs
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【填空题】Lesson four Text A Cloze magnetic instrument threshold designation pavement stripes continuous centerline arranged Runway Markings Runway ___1___ markings are numbers and letters that identify a runway. The number is determined from the approach direction. It is based on the ___2____ heading of the runway centerline. The letters differentiate between left (L), right (R), or center (C) parallel runways, as applicable. Runway ___3___ markings identify the center of the runway and provide alignment guidance to aircraft during takeoff and landing. The stripes are 120′ in length with 80′ gaps. Runway aiming point markings serve as a visual aiming point for a landing aircraft. These two rectangular markings consist of a broad white stripe located on each side of the runway centerline and approximately 1,000′ from the landing threshold. The markings are 100′ to 150′ in length depending on the runway length. Runway touchdown zone markers identify the touchdown zone for landing operations. These markings provide distance information in 500′ increments. These markings consist of groups of one, two, and three rectangular bars symmetrically ___4____ in pairs about the runway centerline. Runway side stripe markings consist of ___5___ white stripes located on each side of the runway. These markings provide a visual contrast between runway ___6____ and the ground. Runway shoulder markings consist of continuous yellow ____7__ that are used when needed to identify pavement next to the runway that is not intended for use by aircraft. Runway ___8____ markings identify the beginning of the runway that is available for landing. Runway threshold markings come in two configurations. These markings have eight stripes of uniform dimensions, or the number of stripes is related to the runway width. Visual runways, those without an___9____ approach, do not have threshold markings.
