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
Please Fasten Your Seatbelts Severe turbulence(湍流)can kill aircraft passengers. Now, in test flights over the Rocky Mountain
Please Fasten Your Seatbelts Severe turbulence(湍流)can kill aircraft passengers. Now, in test flights over the Rocky Mountain
admin
2016-07-17
57
问题
Please Fasten Your Seatbelts
Severe turbulence(湍流)can kill aircraft passengers. Now, in test flights over the Rocky Mountains, NASA(美国航空航天局)engineers have successfully detected clear-air turbulence up to 10 seconds before an aircraft hits it.
Clear-air turbulence often catches pilots by surprise. Invisible to radar, it is difficult to forecast and can hurl(用力抛出去)passengers about the cabin. In December 1997, one passenger died and a hundred others were injured when unexpected rough air caused a United Airlines flight over the Pacific to drop 300 meters in a few seconds.
However, passengers can avoid serious injury by fastening their seatbelts. "It is the only antidote(对策)for this sort of thing, " says Rod Bogue, project manager at NASA’s Dryden Flight Research Center in Edwards, California.
The centre’s new turbulence detector is based on lidar, or laser radar. Laser pulses are sent ahead of the plane and these are then reflected back by particles in the air. The technique depends on the Doppler effect. The wavelength of the light shifts according to the speed at which the particles are approaching. In calm air, the speed equals the plane’s airspeed. But as the particles swirl(打漩)in rough air, their speed of approach increases or decreases rapidly. The rate of change in speed corresponds to the severity(激烈程度)of the turbulence.
In a series of tests that began last month, a research jet flew repeatedly into disturbed air over the mountain ridges(山脉)near Pueblo, Colorado. The lidar detector spotted turbulence between 3 and 8 kilometers ahead, and its forecasts of strength and duration corresponded closely with the turbulence that the plane encountered.
Bogue says that he had "a comfortable amount of time" to fasten his seatbelt. The researchers are planning to improve the lidar’s range with a more powerful beam. The system could be installed on commercial aircraft in the next few years.
In December 1997, a United Airlines flight hit unexpected rough air, ______.
选项
A、causing a lot of damage to the plane
B、throwing its passengers out of the cabin
C、resulting in heavy casualties
D、forcing the pilot to make an emergency landing
答案
C
解析
该题问的是1997年12月联合航空公司的一架班机在碰到这种气流后,遭遇了什么结果?原文讲到造成一人死亡,多人受伤,据此判断,损失惨重,故选C。
转载请注明原文地址:https://kaotiyun.com/show/wbLd777K
本试题收录于:
职称英语理工类B级题库职称英语分类
0
职称英语理工类B级
职称英语
相关试题推荐
Inprevioustimes,whenfreshmeatwasinadequate,pigeonswerekeptbymanyhouseholdsasasourceoffood.
CulturalDifferencesPeoplefromdifferentculturessometimesdothingsthatmakeeachotheruncomfortable,sometimeswithou
CannedFoods:ConvenienceandNutritionMeetingyourfamily’snutritionalneedsmayseemdifficultconsideringtoday’sbusyl
Accordingtothepassage,theriskofachilddevelopinginsulin-dependentdiabetesislinkedtoallthefollowingfactorsEXCEP
AKeepingGoodRelationswithLocalBusinessmenBServiceProvidedbyLocalNewspapersCLargeCirculationoftheNationalNe
TheIcemanOnaSeptemberdayin1991,twoGermanswereclimbingthemountainsbetweenAustriaandItaly.Highuponamount
MobilePhonesMobilephonesshouldcarryalabeliftheyprovedtobeadangeroussourceofradiation,accordingtoRobertBell,
PlantGasScientistshavebeenstudyingnaturalsourcesofmethanefordecadesbuthadn’tregardedplantsasaproducer,notesF
Comparedwithadultslearningaforeignlanguage,childrenlearntheirnativelanguagewithease.Gesturesandfacialexpressio
随机试题
某高速公路工程针对影响道路质量的弯沉值、平整度、摩阻系数、横坡、纵坡、路面宽度和路基宽度7个指标检测了。1380m长的路段,得到这7项指标不合格频数分别为27、22、17、39、21、27、2,按照排列图法分析影响质量的主要因素有()。
在操作热处理炉之前需检查设备、仪表是否运转正常。()
在CIF下。卖方的主要义务。
下列哪项不是薄荷的主治病证
位于腺泡和小导管外,扁平状,有分枝状突起的细胞是
世界上的汇率制度主要有()。
为了最终实现目标系统,必须设计出组成这个系统的所有程序和文件,通常分为两个阶段完成,即过程设计和
下列四条叙述中,正确的一条是__________。
Tomisstillfullofbeansat70.
Thisnewly______dishwashercanhold20percentmoredishesthanthepreviousmodelofthesamesize.
最新回复
(
0
)