飛機上到底能不能使用電子設備？

Love it or hate it, flying is necessary if we want to get to a faraway destination. For those of us who love to read e-books or listen to music on our phone to pass the time, however, taking a flight in China can be a boring experience.

不論你喜歡與否，想要到一個遙遠的地方去，搭乘飛機就成了必要的選擇。然而，對于我們之中喜歡在手機上看電子書或者聽音樂的人而言，在中國坐飛機是場很無聊的體驗。

This is because Chinese airlines didn’t allow smartphones to be powered on during flights, even in flight mode. However, since Oct 1, airlines are now allowed to lift the ban if they wish.

這是因為中國的航空公司不允許乘客在飛行期間打開手機，甚至連飛行模式也不行。但從今年10月1日開始，航空公司可以自行選擇取消這項禁令。

The reason behind the ban is something called electromagnetic interference. This is when electrical signals mess with other electronic equipment, causing them to react in unusual ways.

這項禁令背后的原因在于一種名為電磁干擾的現(xiàn)象。當電子信號遇上其他電子設備時，會產(chǎn)生一些不尋常的反應。

And according to a study by plane manufacturer Boeing in 2014 published by CNN, electromagnetic interference can sometimes cause flight equipment to react, too.

根據(jù)CNN2014年發(fā)布的一份飛機制造商波音公司的研究顯示，電磁干擾有時也會對飛行設備產(chǎn)生影響。

During the study, Kenny Kirchoff, a Boeing engineer, measured the radio signals sent out by a laptop’s Wi-Fi radio.

在研究中，波音公司工程師肯尼·基爾霍夫測量了一臺筆記本電腦的無線上網(wǎng)功能所發(fā)出的無線電信號。

“You can see that some of the signals from the laptop actually jump over the limit,”Kirchoff told CNN at the time.

“你可以發(fā)現(xiàn)，筆記本電腦的一些信號事實上已經(jīng)超出了界限，”基爾霍夫當時在接受CNN采訪時表示。

“So that means there’s a potential that this piece of equipment could interfere with [plane instruments].”

“所以這意味著，這臺設備很有可能會干擾(飛機上的儀器)。”

This issue is worse with mobile phones, which constantly send and receive strong signals while they search for a connection to the network. Even in flight mode, many phones still do this.

這個問題在手機上表現(xiàn)得更為嚴重：當手機在搜索網(wǎng)絡連接時，會不斷發(fā)出并接收強信號。就算使用了飛行模式，不少手機也是如此。

Despite this, there were just 29 cases of electromagnetic interference caused by mobile phones reported worldwide between 2003 and 2009, according to CNN.

據(jù)CNN報道，盡管如此，在2003-2009年間，全球范圍內(nèi)記錄的由手機引起的電磁干擾現(xiàn)象只有29例。

Besides, the instruments in modern planes are protected from electromagnetic interference by metal “shields”.

此外，現(xiàn)代飛機上的儀器都被“金鐘罩”保護著，不受電磁干擾。

You’ve probably already seen this technology if you’ve ever seen the inside of a TV cable.

如果你曾看過電視電纜的內(nèi)部結構的話，大概就已經(jīng)見識過這一技術了。

Covering the main wire in the center are often two or three layers of metal that protect the TV signal from outside interference caused by other devices.

中間的主接線之外通常還包裹著兩三層金屬，保護電視信號不受其他設備的外來干擾。

Similarly, the metal box design of microwave ovens keeps the interference they create from escaping.

同理，微波爐金屬盒子的外形設計也鎖住了其自身產(chǎn)生的電磁干擾。

Many Chinese airlines are now expected to allow passengers to use their smartphones freely, meaning that we can finally catch up on our favorite books and songs while at 30,000 feet in the air.

國內(nèi)的許多航空公司如今都希望能夠允許乘客隨意使用智能手機，這意味著，我們終于能在30000英尺的高空中看書和聽歌了。