How does turbulence occur on aircrafts, and is it dangerous?
搭機時，亂流是怎麼發生的，那會危險嗎？
Meet family Meier, up in the air and excited, on their way to a fantastic holiday full of sunshine, fun, and relaxation. But suddenly, the whole plane starts to shake. The kids get scared and think it'll crash. Their parents calm them down and explain that these vibrations called turbulence are normal and caused by the irregular motion of airflows. Although it may feel scary, it's completely harmless. And usually, turbulence is over quickly, just like now.
見見梅爾一家人，興高采烈地在萬里高空上，正前往度過充滿陽光、休閒娛樂的美好假期。但突然間，整架飛機開始晃動。孩子們很害怕，覺得飛機就要墜毀了。他們的爸媽安撫他們，向他們解釋這些叫作亂流的震動很正常，那是因為氣流的不規則運動所造成的。雖然可能感覺起來很嚇人，這卻完全不會造成傷害。而且亂流通常很快就結束了，就像現在一樣。
Flight attendant Olivia overhears the family's conversation and is happy to share her knowledge. She explains that planes, especially their wings, are designed to be flexible. This way, they're able to withstand high forces and won't break due to turbulence.
空服員奧莉薇無意間聽到這家人的對話，而她很樂意分享她的知識。她說明飛機，特別是它們的機翼，被設計成具有彈性。這樣一來，飛機就能承受巨大力量，且不會因亂流而損壞。
Additionally, there are three types of turbulence. The first one is thermal turbulence, created by rising air like cumulus clouds or thunderstorms. Mechanical turbulence, however, depends on landscape and obstacles. Along mountains, for example, strong up-and-down winds rise. Olivia mentions that proceeding planes cause mechanical turbulence, too. That's why the pilot had to wait a few minutes before taking off. The third type of turbulence is triggered by wind shears, such as when flying in or out of a jet stream. This has been the case just now.
此外，亂流分成三種。第一種是熱亂流，由積雲或雷雨那類上升氣流生成。而機械性亂流則是視地景與障礙而產生。好比說，沿著山脈會有上下起伏的強風出現。奧莉薇提到前方的飛機也會造成機械性亂流。那就是為什麼飛行員在起飛前要先等幾分鐘。第三種亂流是由風切所引起，例如飛進或飛離一個高速氣流時。這就是現在遇到的情形。
Olivia stresses that there's nothing to worry about. The cockpit crew constantly checks the weather radar for thunderstorm zones. Furthermore, flight controllers inform crews about possible turbulence after getting messages from other planes. So, usually the pilot recognizes turbulence early and is able to fly around it or forewarn passengers.
奧莉薇強調沒有什麼好擔心的。駕艙組員會不斷檢查氣象雷達以知道雷雨活動區。此外，飛行控制器會告知組員可能存在的亂流，在從其它飛機接收到訊息後。因此，飛行員通常會提早發現亂流，並能夠繞過它或提前警告乘客。
The family Meier listens carefully. The kids ask what happens if the cockpit crew can't foresee turbulence. Olivia explains that sometimes, unpredictable clear air turbulences occur, since there are always different airflows. But overall, turbulence usually is not strong. There are four levels: light, moderate, severe, and extreme turbulence. Severe and extreme types occur very rarely. When passengers keep their seat belts fastened throughout the whole flight, nothing can happen at all.
梅爾一家人很認真地聽。小朋友們問道如果駕艙組員沒辦法預見亂流發生會怎麼樣。奧莉薇解釋有時候會有無法預料的晴空亂流發生，因為天空總是存在著不同氣流。但整體來說，亂流通常都不強。亂流有四個等級：輕度、中度、強烈和極度亂流。強烈和極度亂流非常少發生。當乘客們整趟旅途中都繫好安全帶時，就什麼事都不會發生了。
Greatly reassured, the kids and their parents enjoy the rest of the flight and a safe landing. Now, their vacation can begin.
內心感到踏實許多，孩子們和他們的父母享受剩下的搭機旅途以及平安的降落。現在，他們的假期可以展開了。
- 「使...平靜、鎮定下來」- Calm Down
Their parents calm them down and explain that these vibrations called turbulence are normal and caused by the irregular motion of airflows.
他們的爸媽安撫他們，向他們解釋這些叫作亂流的震動很正常，那是因為氣流的不規則運動所造成的。 - 「因為、由於」- Due To
This way, they're able to withstand high forces and won't break due to turbulence.
這樣一來，飛機就能承受巨大力量，且不會因亂流而損壞。 - 「起飛」- Take Off
That's why the pilot had to wait a few minutes before taking off.
那就是為什麼飛行員在起飛前要先等幾分鐘。
