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

admin2015-06-23  20

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°F. 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D

解析 推理题。由题干中的the black box定位在文章开头。从这一段对黑匣子的描述,每次乘飞机都和它在一起,能记录下你要去的地点、飞行建度以及飞机上的一切是否正常运转,能经受任何灾难等特点。从而推断出黑匣子是飞机上必不可少的设备,故本题选D。黑匣子是记录飞机是否正常发挥功能,而不是保证其发挥功能,故A项错误,文中提到漫画书是为了突显黑匣子的神奇,而不是说发明黑匣子的是感源于漫画书,选项B的说法不正确。文中是说黑匣子能经受任何灾害,并不是说他具有防灾避难的能力,属于推理过度,故选项C也错误。
转载请注明原文地址:https://jikaoti.com/ti/Ia3FFFFM
0

相关试题推荐
最新回复(0)