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
2024-10-15
2
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 airplane 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 an aircraft that can be made to fly. Out of that weight as much as possible is wanted for fuel, radio navigational instruments, passenger seats, or freight 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 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.
When a plane has passed all the tests it can get a government certificate of airworthiness, without which it is illegal to fly, except for test flying.
Making the working parts reliable is as difficult as making the structure strong enough. The flying controls, the electrical equipment, the fire precautions, etc. must not only be light in weight, but must work both at high altitudes where the temperature may be below freezing point and in the hot air of an airfield in the tropics.
To solve all these problems the aircraft industry has a large number of research workers, with elaborate laboratories and test houses, and new materials to give the best strength in relation to weight are constantly being tested. [br] The maximum possible weight of an aircraft is determined by______.
选项
A、the engine power
B、the amount of freight room
C、the number of passengers
D、international regulations
答案
A
解析
本题询问飞机的重量取决于什么因素。相关信息在文章第二段,关键语句为“Given a certain power of engine,and consequently a certain fuel consumption,there is a practical limit to the total weight of an aircraft that can be made to fly”。
转载请注明原文地址:https://tihaiku.com/zcyy/3802477.html
相关试题推荐
Therearetwomainthingsthatmakeaircraftengineeringdifficult,theneed
Therearetwomainthingsthatmakeaircraftengineeringdifficult,theneed
Therearetwomainthingsthatmakeaircraftengineeringdifficult,theneed
Ifyoufindthisitemtoodifficulttoitisadvisabletoleaveasitisandmov
_______isthecenterofourplanetarysystemwasadifficultconcepttograspi
Theteacheraskedaverydifficultquestion,butfinallyTed_____asatisfactory
Whatcausesasorethroat?Manythingscancauseasorethroat.Theseca
Whatcausesasorethroat?Manythingscancauseasorethroat.Theseca
Whatcausesasorethroat?Manythingscancauseasorethroat.Theseca
Theyovercameallthedifficultiesandcompletedtheprojecttwomonthsaheadof
随机试题
Don’t______thatrope,oryoumightfall.A、getridofB、letgoofC、letaloneD、p
BritishColumbiahasgreatervariationsinclimatethananyotherprovinceinCa
[originaltext]W:IthoughtIwasspeakingEnglishfairlywell,butpeoplekeep
Youshouldspendabout20minutesonQuestions1-13,whicharebasedonReading
书面需求报告包括对客户需求的分析报告和()两种。
生态位
与“赠地学院”的出现有关的院校职能是()。A.科研 B.社会服务 C.教学
患者,男性,70岁。冠心病史10余年,冠状动脉造影检查后出现恶心、食欲缺乏。尿量
患者,男,56岁,肝硬化。因使用大剂量排钾利尿剂后,并发肝性脑病,出现烦躁不安,
“确定排水体制”属于下列哪一项规划阶段的内容?( )A.城市总体规划 B.城
最新回复
(
0
)