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
You never see them, but they’re with you every time you fly. They record where you are going, how fast you’re traveling and whet
You never see them, but they’re with you every time you fly. They record where you are going, how fast you’re traveling and whet
admin
2015-02-09
60
问题
You never see them, but they’re with you every time you fly. They record where you are going, how fast you’re traveling and whether everything on your airplane is functioning normally. Their ability to withstand almost any disaster makes them seem like something out of a comic book. They’re known as the black box.
When planes fall from the sky, as a Yemeni airliner did on its way to Comoros Islands in the India ocean June 30, 2009, the black box is the best bet for identifying what went wrong. So when a French submarine(潜水艇)detected the device’s homing signal five days later, the discovery marked a huge step toward determining the cause of a tragedy in which 152 passengers were killed.
In 1958, Australian scientist David Warren developed a flight-memory recorder that would track basic information like altitude and direction. That was the first mode for a black box, which became a requirement on all U.S. commercial flights by 1960. Early models often failed to withstand crashes, however, so in 1965 the device was completely redesigned and moved to the rear of the plane - the area least subject to impact - from its original position in the landing wells(起落架舱). The same year, the Federal Aviation Authority required that the boxes, which were never actually black, be painted orange or yellow to aid visibility.
Modern airplanes have two black boxes: a voice recorder, which tracks pilots’ conversations, and a flight-data recorder, which monitors fuel levels, engine noises and other operating functions that help investigators reconstruct the aircraft’s final moments. Placed in an insulated(隔绝的)case and surrounded by a quarter-inch-thick panels of stainless steel, the boxes can withstand massive force and temperatures up to 2,000℉. When submerged, they’re also able to emit signals from depths of 20,000 ft. Experts believe the boxes from Air France Flight 447, which crashed near Brazil on June 1, 2009, are in water nearly that deep, but statistics say they’re still likely to turn up. In the approximately 20 deep-sea crashes over the past 30 years, only one plane’s black boxes were never recovered.
What does the author say about the black box?
选项
A、It ensures the normal functioning of an airplane.
B、The idea for its design comes from a comic book.
C、Its ability to ward off disasters is incredible.
D、It is an indispensable device on an airplane.
答案
C
解析
转载请注明原文地址:https://kaotiyun.com/show/cOq7777K
0
大学英语四级
相关试题推荐
Forthispart,youareallowed30minutestowriteashortessayentitledStudyingAbroadfollowingtheoutlinegivenbelow.You
PreparingforMoreExpensiveDegreesinEnglandA)Balancingatightbudgetisoneofthemostdifficultaspectsofbeingastude
A、Themanshouldpracticehispronunciationoften.B、Togetoneselfunderstoodismoreimportantthanpronunciation.C、Shehasa
ShoppersonBlackFriday,thetraditionalstartoftheholidayshoppingseasoninAmerica,arenotoriouslyaggressive.Someeven
Lessthan60%ofstudentsnowenteringfour-yearAmericancollegesarelikelytograduate.The【B1】______rateislowerthanfora
Lessthan60%ofstudentsnowenteringfour-yearAmericancollegesarelikelytograduate.The【B1】______rateislowerthanfora
Forthispart,youareallowed30minutestowriteashortessay.Youshouldstartyouressaywithabriefdescriptionofthepi
Wisebuyingisapositivewayinwhichyoucanmakeyourmoneygofurther.Thewayyougoaboutpurchasinganarticleoraservi
A、Lovestories.B、Detectivestories.C、Storiesaboutjailescapes.D、Storiesaboutroyalfamilies.A对话中女士提到I’mtiredofthemovi
Heredity(遗传)isnottheonlythingthatinfluencesourcolour.Whereandhowweliveafterwearebornisimportanttoo.Forinst
随机试题
2岁男孩,发热、咳嗽、恶心、腹痛1天,昏迷半天,呼气中有烂苹果味。该患儿昏迷最可能的原因是
Skepticsofhighereducationoftencomplainthatuniversitiesoffertoomanyboringdegreeswithlittlevalueintheworkplace.【
我国土地权属争议的处理,经过国土资源管理部门多年的努力工作,目前遗留的土地权属争议大都表现为()等特点。
下列关于票据特征的表述中,正确的有()。
利润表中应单独列示的项目有( )。
学生在学习过程中遇到自己无法克服的困难,向别人求助是一种依赖性的表现。()
被认为是推开17世纪现实主义艺术大门的人是意大利画家_______,其代表作有《_______》。
第二次世界大战后,资本主义的新变化是客观事实。正确认识这些新变化,有助于我们洞察资本主义的实质。当代资本主义新变化
某二叉树共有12个结点,其中叶子结点只有1个。则该二叉树的深度为(根结点在第1层)
Whereisthewoman?
最新回复
(
0
)