首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
There are two main things that make aircraft engineering difficult: the need to make every component as reliable as possible and
There are two main things that make aircraft engineering difficult: the need to make every component as reliable as possible and
admin
2015-12-31
58
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.
The two main requirements of aircraft design are______.
选项
A、ability to stay up in the air and ability to avoid breakdowns
B、making things both light and dependable
C、reliability and passenger comfort
D、speed and inexpensiveness
答案
B
解析
本题问飞机设计时的两个主要要求是什么。文章第一段指出,飞机制造工程面临两个主要难题:一是要把每个部件都做得尽可能可靠,二是尽可能减轻每个部件的重量。飞机一旦到达空中,如若发生故障也不可能停下来,所以,飞机的性能要绝对可靠,这也许是个生死攸关的事情。因此,本题的正确答案应是B“飞机上的部件要重量轻且可靠性强”。
转载请注明原文地址:https://kaotiyun.com/show/3mPO777K
0
在职攻硕英语联考
相关试题推荐
Thebraindrain(人才流失)isauniversalphenomenon,andcountriesthatdon’tfaceuptothenewrealitywillbelosingsomeofthe
Man:Didyoutakeyourchildrenoutlastweekend?Woman:Yes.Andtheyhadthetimeoftheirlivesattheamusementpark.Quest
Woman:Howwasthejobinterview?Ithinkyou’llmakeagoodjournalist.Irememberyouasthebestwriteroftheclass.Man:We
Mostoftheplansandprogramsfordiminishingcrimebymeansofcomprehensivecommunityorganizationhavemadepreventiontheir
Inscience,atheoryisareasonableexplanationofobservedeventsthatarerelated.Atheoryofteninvolvesanimaginarymodel
Theideaofbuilding"NewTowns"toabsorbgrowthisfrequentlyconsideredacure-allforurbanproblems.Itiswronglyassumed
Themostfundamentalgrouptowhichapersonbelongsisthefamily.Theinstitutionofthefamilyexistsinalmosteveryhumanc
Artificialflowersareusedforscientificaswellasfordecorativepurposes.Theyaremadefrom【C1】______ofmaterials,suchas
ThekeytotheindustrializationofspaceistheU.S.spaceshuttle.【C1】______it,astronautswillacquireaworkhousevehicle【C
SpeakerA:I’mgoingtotheparkwithsomefriendsforabarbecueonSunday.Wouldyouliketojoinus?SpeakerB:______
随机试题
A.动脉球嵴B.肌性室间隔C.二者均是D.二者均否原始心室的分隔()
男,11岁。左下后牙疼4天,夜间加重1天,无龋洞。最可能的诊断是
A.补肾安胎饮B.胎元饮C.保阴煎D.加味圣愈汤E.桃红四物汤跌仆损伤而致的早产治疗方剂为
税源是指税收的经济来源或最终出处,各种税收的经济来源相同。()
公路工程施工现场施工人员管理中,编制订员的基本依据是()。
关于耕地占用税的说法。正确的有()。(2010年)
两个以上人民法院都有管辖权的诉讼,原告可以向其中一个人民法院起诉;原告向两个以上有管辖权的人民法院起诉的,由最先收到起诉状的人民法院管辖。()
某企业只生产一种产品,当年的税前利润为20000元。运用本量利关系对影响税前利润的各因索进行敏感分析后得出,单价的敏感系数为4,单位变动成本的敏感系数为-2.5,销售量的敏感系数为5,固定成本的敏感系数为-0.5。下列说法中,正确的有()。(2011
变化与()是图案设计的总则,它来源于对自然规律的辩证分析。
PsychologistsatQowl,aprivatefirmlinkedtotheUniversityofPortsmouthanalyzedthequalityofworkinglifeofabout5000
最新回复
(
0
)