首页
登录
职称英语
There are two main things that make aircraft engineering difficult: the need
There are two main things that make aircraft engineering difficult: the need
游客
2025-03-21
22
管理
问题
There are two main things that make aircraft engineering difficult: the need to make every component as reliable as possible and the need to build everything as light as possible. The fact that an aeroplane is up in the air and cannot stop if anything goes wrong makes it perhaps a matter of life or death that its performance is absolutely dependable.
Given a certain power of engine, and consequently a certain fuel consumption, there is a practical limit to the total weight of aircraft that can be made to fly. Out of that weight as much as possible is wanted for fuel, radio navigational (航行的,航运的) instruments, passenger seats, or freight (货物) room, and, of course, the passengers or freight themselves. So the structure of the aircraft has to be as small and light as safety and efficiency will allow. The designer must calculate the normal load that each part will bear. This specialist is called the "stress man". He takes account of any unusual stress that may be put on the part as a precaution (预防, 预防措施) against errors in manufacture, accidental damage, etc.
The stress man’s calculations go to the designer of the part, and he must make it as strong as the stress man says is necessary. One or two samples are always tested to prove that they are as strong as the designer intended. Each separate part is tested, then a whole assembly—for example, a complete wing, and finally the whole aeroplane. When a new type of aeroplane is being made, normally only one of the first three made will be flown. Two will be destroyed on the ground in structural tests. The third one will be tested in the air. [br] The first three aeroplanes of a new type______.
选项
A、are used for testing purposes
B、are later broken up for spare parts
C、do not fly
D、are all destroyed
答案
A
解析
本题问新型飞机的前三架用于什么目的。文章第三段最后两句话指出,当一个新型飞机制作完毕,一般前三架中仅试飞一架。其中两架将在地面拆毁,用于结构检测,第三架接受空中检测。因此,本题的正确答案应是A“新型飞机的前三架用于测试目的”。
转载请注明原文地址:https://tihaiku.com/zcyy/4006825.html
相关试题推荐
Revengeisoneofthosethingsthateveryoneenjoys.Peopledon’tliketota
Revengeisoneofthosethingsthateveryoneenjoys.Peopledon’tliketota
Revengeisoneofthosethingsthateveryoneenjoys.Peopledon’tliketota
Theconceptof"environment"iscertainlydifficultandmayevenbemisunder
Theconceptof"environment"iscertainlydifficultandmayevenbemisunder
Theconceptof"environment"iscertainlydifficultandmayevenbemisunder
NancyJeschke’ssleepingdifficultiesbeganonvacationafewsummersago.S
NancyJeschke’ssleepingdifficultiesbeganonvacationafewsummersago.S
Moresurprising,perhaps,thanthecurrentdifficultiesoftraditionalmarri
Moresurprising,perhaps,thanthecurrentdifficultiesoftraditionalmarri
随机试题
Mannersaredifferentineverycountry;buttruepolitenessiseverywhereth
【C1】______snakes,lizards,andcrocodiles,turtlesbelongtotheclassof
消防用电设备的配电线路可以明敷的电缆为:()。A.阻燃耐火电缆 B.矿物绝缘
促进非血红素铁吸收的有A.多酚类 B.畜、鱼肉 C.磷酸盐 D.植酸 E
某游客因其同房的另一位游客常常回来很晚,影响其休息,遂向地陪提出住单间的要求。此
共用题干 FreeStatinswithFastFoodcould
关于膜材的表述错误的是A.乙烯-醋酸乙烯共聚物的英文缩写为E.VA. B.PV
下列关于口腔鳞状细胞癌的描述,不正确的是A:是口腔中最常见的恶性肿瘤 B:男性
在道路货物运输组织中,拖挂运输一般可分为定挂运输和()。A.驼背运输 B.半挂
进行技术经济分析,确定最佳的施工方案,属于施工成本管理措施中的()。A.合同措施
最新回复
(
0
)