首页
登录
职称英语
[originaltext] For centuries men dreamed of achieving vertical flight, The a
[originaltext] For centuries men dreamed of achieving vertical flight, The a
游客
2024-02-14
22
管理
问题
For centuries men dreamed of achieving vertical flight, The ancient dream was finally, realized in 1940 when a Russian engineer piloted a strange looking craft of steel tubing with a rotating fan on top. It rose awkwardly and vertically into the air from a standing start, hovered a few feet above the ground, went sideways and backwards, and then settled back to earth. The vehicle was called a helicopter.
Imaginations were fired. Men dreamed of going to work in their own personal helicopters. People anticipate that vertical flight transports would carry millions of passengers as the airliners of today do. Such fantastic expectations were not fulfilled. The helicopter has now become an extremely useful machine. It excels in military missions, carrying troops, guns and strategic instruments where other aircraft cannot go. Corporations use them as airborne offices, many metropolitan areas use them in police work, construction and logging companies employ them in various advantageous ways, engineers use them for site selection and surveying, and oil companies use them as the best way to make offshore and remote work stations accessible to crews and supplies. Any urgent mission to a hard-to-get-to place is a likely task for a helicopter. Among their other multitude of uses: deliver people across town, fly to and from airports, assist in rescue work, and aid in the search for missing or wanted persons.
选项
A、For high speed transportation.
B、For extremely high altitude flights.
C、For overseas passenger transportation.
D、For urgent mission to places inaccessible to other kinds of craft.
答案
D
解析
Under what conditions are helicopters found to be absolutely essential?
转载请注明原文地址:https://tihaiku.com/zcyy/3449113.html
相关试题推荐
[originaltext]Scientistshaveobservedthatplantsthemselvesproducemany
[originaltext]W:EnglishLanguageCenter.HowmayIhelpyou?M:Yes.I’mcalli
[originaltext]W:Hello.Mr.Summerfield.Howareyoutoday?M:Verywell.Thank
[originaltext]W:Hello.Mr.Summerfield.Howareyoutoday?M:Verywell.Thank
[originaltext]W:Hello.Mr.Summerfield.Howareyoutoday?M:Verywell.Thank
[originaltext]M:I’dliketoorderpieandicecreamfordessert.Wouldyouwan
[originaltext]M:I’dliketoorderpieandicecreamfordessert.Wouldyouwan
[originaltext]M:I’dliketoorderpieandicecreamfordessert.Wouldyouwan
[originaltext]Withtheintroductionofradio,newspaperpublisherswondered
[originaltext]Withtheintroductionofradio,newspaperpublisherswondered
随机试题
WhatisthepurposeofMrs.Harris’visittotheheadmaster?[br][originaltext
Today,somecriticsarguethatprogressonenvironmentalproblemshasbeene
Therulesofthegameareanarbitraryimpositionofdifficulty.这个游戏的规则就是将困难武断地强
关于隧道防水设施施工监理事项,铺设塑料防水板应在初支护变形基本稳定和在二次衬砌灌
A.3个 B.4个 C.6个 D.9个 E.12个
银行在受理借款人个人抵押授信贷款业务时,不能接受的抵押物是()。A.借款人全
中小企业板块的设计要点有()。 Ⅰ.暂不降低发行上市标准 Ⅱ.尽可能扩大行
Thechangeinthatvillagewasmiraculou
A房地产开发商开发的居住小区一期已经入住,当时的物业管理工作由A房地产开发商的物
森林里一群猴子发现水里有个月亮,以为月亮掉水里会引发森林灾难。于是大家组织捞月,
最新回复
(
0
)