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 isolated (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.

【江苏省2014届高三英语一轮复习 阅读理解攻略训练（7）】相关文章：

★ 2017届高考英语二轮复习课时训练：2（含解析）

★ 贵州省贵阳市2014高考英语（新人教版）一轮阅读训练（35）附答案

★ 四川省2016届高考英语一轮复习课时作业（29） Module 5 The Great Sports Personality 外研版必修5

★ 贵州省贵阳市2014高考英语（新人教版）一轮阅读训练（8）附答案

★ 2017高考四川省广安市英语阅读理解一轮系列训练：16（含解析）

★ 贵州省贵阳市2014高考英语（新人教版）一轮阅读训练（20）附答案

★ 【人教版】2014届高考英语一轮复习指导考点针对练：必修4 unit5《Theme parks》

★ 河南省三门峡市2014高考英语一轮（暑假）基础训练（1）附答案

★ 湖南省长沙县实验中学2016届高三英语二轮复习书面表达复习重点话题指导专题10 旅游探险类话题指导（学生版）

★ 四川省2016届高考英语一轮复习课时作业（46） Module 4 Which English 外研版选修8