亂流顛簸 空中旅行的頭號安全殺手

He had taken a few hard hits as a quarterback for the Ottawa Rough Riders of the Canadian Football League.

擔任加拿大全加足聯渥太華莽騎兵隊四分衛的時候，他也受過幾次重擊。

But when his American Airlines flight on Jan. 25 from Miami to Milan, a Boeing 767 carrying 192 passengers, blew sideways, Jordan Case thought that was it.

不過，1月25日那天，當喬登‧凱斯(Jordan Case)搭着美國航空公司(American Airlines)自邁阿密飛往米蘭的班機遭遇強氣流的時候，他覺得大限到了。那是一架波音767客機，機上有乘客192人。

“I’ve always been a nervous flier and you’re used to bumpy turbulence,” he said. “It happened all of a sudden, just a huge jolt. It was loud and happened twice.”

“我搭飛機時向來緊張，也常遇見亂流顛簸，”凱斯說。“這次來得很突然，機身猛烈顛了一下，發出巨響，總共來了兩次。”

Seated in business class with his wife, Karen, Mr. Case — who owns three luxury car dealerships in Plano, Tex. — said the experience was “horrific.”

凱斯是德州普萊諾市三家高檔汽車經銷店的老闆。亂流發生時，他與妻子凱倫坐在商務艙裏。凱斯說，那次經歷“太可怕了”。

The flight, which hit severe clear air turbulence at 29,000 feet, 420 nautical miles southeast of St. John’s airport in Newfoundland, was diverted to that airport, and two passengers and three flight attendants were taken to the hospital for treatment and observation.

這架飛機遇上激烈的晴空亂流的時候，位於距紐芬蘭聖約翰機場東南420海里、2.9萬英尺的高空。班機變更航線，降落在了聖約翰，機上有兩名乘客及三名空服人員被送到醫院接受治療與觀察。

The couple flew on to Milan the next day, and Mr. Case has flown several times since.

凱斯夫婦第二天繼續飛往米蘭。那以後，凱斯又有過幾次飛行經歷。

Turbulence is the leading cause of injuries to passengers and crew aboard commercial aircraft, according to the Federal Aviation Administration.

根據美國聯邦航空管理局(Federal Aviation Administration)的數據，亂流是導致民航乘客與空服人員受傷的主要原因。

In 2015, 21 people — 14 crew members and seven passengers — were injured by turbulence, according to the F.A.A.; in 2014, 31 people were injured, nine crew members and 22 passengers.

航管局的資料顯示，2015年有21人因亂流受傷，其中有14名乘務員、七名乘客；2014年則有31人受傷，分別爲九名乘務員與22名乘客。

The worst recent year was 2010, when 76 people — 25 crew members and 51 passengers — were injured by turbulence.

近年來最糟的是2010年，那年有25名乘務員、51名乘客，共76人因亂流受傷。

There are many different kinds of turbulence, with the most problematic to predict and to avoid being clear air turbulence (which is very difficult to detect using conventional radar). Much of it is typically experienced at cruising altitude.

亂流有很多種，其中晴空亂流最難預測與迴避，常規雷達很難偵測。飛機大多是在巡航高度時遇上晴空亂流的。

In the last few months, at least three commercial flights, two on American Airlines and one on Air Canada, have experienced severe turbulence that resulted in injuries to those on board. In two instances, the flights were diverted to nearby airports so the injured could receive treatment.

近幾個月以來，至少有三架民航飛機遭遇到嚴重亂流，導致機上人員受傷；其中有兩架美國航空、一架加拿大航空班機。這三次中有兩次，飛機改變航線、就近降落其他機場，以便讓傷患接受治療。

Aviation professionals classify turbulence from light to extreme, a form they say is very rare. The challenge of reporting turbulence, several pilots said, is that the reports themselves are subjective.

航空專業人士將亂流分成輕微至極度嚴重的不同等級；根據他們的說法，極度嚴重的亂流十分罕見。一些飛行員說，報告亂流也存在困難，因爲報告本身是主觀的。

While in flight, pilots file Pilot Reports (Pireps) to alert airline dispatchers and other pilots en route of any turbulence they’ve encountered; what one pilot considers mild might feel moderate to another.

飛行員會在飛航時發佈飛行簡報，讓飛行調度員和航線上的其他飛機知道他們遭遇了亂流，提醒他們注意。一位飛行員認爲屬於輕度的亂流，另一位飛行員可能認爲屬於中度。

What aviation professionals know is that a global network on the ground also helps guide every flight.

而航空專業人士明白，全球地勤工作網絡也能協助指引各架航班。

“I call it the safety net,” said John Lanicci, professor of meteorology at Embry-Riddle Aeronautical University in Daytona Beach, Fla. “You have pilots en route chatting, you have the air control centers and the flight dispatchers for the airlines.” If a flight hits severe enough turbulence that injuries result, a medical professional on the ground is also consulted and a decision quickly made whether to divert, land and take the injured to the hospital.

“我把這叫做‘安全網’，”約翰‧朗尼奇(John Lanicci)說。他是佛羅里達戴通納海灘（代託納比奇）的安柏瑞德航空大學(Embry-Riddle Aeronautical University)的氣象學教授。“你有航線上的飛行員相互通話，還有空管中心與各航空公司的班機調度員。”要是有班機遇上嚴重到足以傷人的亂流，地上也有醫學專家可供諮詢，馬上決定是否該更改航線、降落、將傷患送醫。

When flights like American Airlines 206, the one Mr. Case was on, are forced to divert because of turbulence-related injury, it costs airlines both financially and reputationally, said Mark Miller, senior vice president and general manager, decision support at the Weather Company, an IBM business.

IBM旗下的氣象公司(Weather Company)決策支持部高級副總裁與總經理馬克‧米勒(Mark Miller)認爲，如果航班被迫變更航線，比如凱斯乘坐的美國航空206航班遇到的那次，此類事件會導致航空公司受到經濟與名譽上的雙重損失。

Mr. Miller, a meteorologist, said that turbulence can force aircraft to choose less than optimal routes that use more fuel and are less efficient, and the roughest flights can require additional aircraft checks and maintenance.

米勒還是一位氣象學家。他說，亂流會迫使飛機放棄最優航線，選擇更耗油、效率低的航線。最顛簸的航行還會要求對飛機做額外的檢修。

Brand perception is another issue, he added. “It’s a big problem for emerging markets if new fliers see passengers coming off in a neck brace.” And yet, Mr. Miller and Dr. Lanicci agree, some routes are simply more likely to prove bumpy, like Asia-Pacific flights. “It’s a big problem,” Mr. Miller said. If it looks like a flight is going to be rough “that perception can impact demand for air travel.”

米勒還說，品牌形象是另一個問題。 “對新興市場來說，新客戶看到有人脖子裝着支架下飛機，麻煩就大了。”然而米勒與朗尼奇也承認，有些航線就是比較容易顛簸，比如亞太航線。 “這是個大問題，”米勒說。如果一段航程看起來將會顛簸不平，“這種認識就會影響飛行需求”。

The American Airlines flight that the Cases took encountered only a few seconds of turbulence, said a spokesman for the airline, Ross Feinstein, and the plane was not damaged.

美國航空的發言人羅斯‧范士丹(Ross Feinstein)表示，凱斯搭乘的班機僅僅遭遇到數秒鐘的亂流，且機身並未受損。

Aviation crews admit that experiencing turbulence can be frightening and disorienting, even sometimes for them as well, but they emphasize that planes are designed and manufactured to weather it.

乘務人員承認，遇上亂流很可能既恐怖、又讓人暈頭轉向，有時就連對他們來說也是如此。不過他們也強調，飛機的設計和建造是可以承受住亂流的。

“Our airplanes are built to withstand 3.75 G load before there is any kind of damage — that’s almost four times gravity,” said Doug Alder, a spokesman for Boeing. “Some of the worst turbulence gets in the range of 2 to 2.5 G’s, well below the damage tolerance.”

“我們建造的飛機能承受最高達3.75G的衝擊而不會有任何損傷，幾乎是重力的四倍。”波音公司發言人道格‧阿爾德(Doug Alder)表示。 “最嚴重的亂流的衝擊力一般在2到2.5G之間，遠在飛機的耐損限度之下。”

“Flights are diverted because passengers have been injured by turbulence, not because the airplane has been damaged,” he said.

“班機改變航道是因爲有乘客因亂流受傷，而不是因爲飛機受損的緣故。”阿爾德表示。

After events of severe turbulence, aircraft are also carefully examined for any damage to be sure they remain airworthy.

遇上嚴重亂流之後，飛機也會受到仔細檢查，確認是否有任何損傷，確保它們還能繼續飛行。

A study of upper-level turbulence, examining two million pilot reports between January 1994 and December 2005, showed a spike in reports between 1997 and 1998, Dr. Lanicci said, which the study’s authors suggested could be attributed to El Niño.

在一份關於高空亂流的研究中，研究人員檢視了1994年1月至2005年12月間的200萬份飛行簡報。朗尼奇說，結果顯示，亂流報告在1997與1998年間有一個高峯。該研究的作者認爲，原因可能是厄爾尼諾現象。

This year’s El Niño has affected weather patterns worldwide as well.

這一年的厄爾尼諾現象也影響了全球的氣候常模。

“It’s an interesting question,” Dr. Lanicci said when asked if El Niño is currently causing more frequent or more severe turbulence. “Inconclusive,” said David Hosansky, a spokesman for the National Center for Atmospheric Research, a federally funded research and development center.

“這是個有趣的問題。”當被問及厄爾尼諾現象是否正在造成更爲頻繁和嚴重的亂流，朗尼奇如是說。美國國家大氣研究中心(National Center for Atmospheric Research)發言人大衛‧侯山斯基(David Hosansky)則表示：“尚無定論。”該單位爲美國聯邦政府資助的研究發展中心。

As 2015 was also the hottest year so far on record, is there a link between severe turbulence and climate change?

鑑於2015年亦是有史以來最熱的一年，強烈亂流與氣候變化是否有關聯呢？

While a paper published in 2013 in the journal Nature Climate Change said there was a causal link between the two, Dr. Lanicci said that there are too many complex factors to make this connection directly. “Every year is going to be different, so can we also go back to every turbulence report and correlate it to climate change?” he said. “There are too many things that could contribute to that.”

雖然《自然氣候變化》(Nature Climate Change)在2013年刊載的一份研究宣稱兩者間有因果關係，不過朗尼奇表示，還有太多複雜因素，很難確定亂流與氣候變化的直接關係。 “每一年都會不一樣，難道我們能去追溯每一次亂流報告，然後找出它和氣候變化的關聯嗎？”他說。 “有太多因素會導致亂流。”

Passengers who fly a great deal can become blasé and forget to stay firmly buckled in, or start to ignore warnings when anticipated turbulence doesn’t happen, airline crews said.

乘務人員表示，常乘坐飛機的旅客可能會見怪不怪、忘了全程繫好安全帶，或者因爲預計的亂流沒有發生而無視警告。

It’s a risk to avoid.

應該避免這種風險。

The problem with light turbulence is that it can turn into severe turbulence in a matter of seconds. Those not securely strapped into their seats can, and have, flown into galley carts, arm rests or the ceiling, breaking hips, arms and noses and risking concussion.

輕度亂流的問題在於，它可能在轉瞬間變得十分強烈。那些沒有留在座位上繫好安全帶的乘客，有可能會撞上服務推車、座椅扶手或天花板，撞斷自己的髖骨、手臂、鼻子，甚至有腦震盪的危險。此類狀況已有先例。

In a highly competitive industry, flight crews must balance offering service with keeping passengers and crew safe. Once an announcement has been made instructing crew to remain seated — marking a period of anticipated intense turbulence — anyone not wearing a seatbelt is at risk.

在這個競爭激烈的行業，乘務員一定要在提供服務與維護乘客與同事的安全間取得平衡。一旦廣播指示機組人員留在座位上——這是預計將有強烈亂流的信號——此時任何未系安全帶的人都可能有危險。

Each airline has dozens of meteorologists on staff helping to plan and guide their flights to avoid turbulence whenever possible, and pilots have access to a wealth of real-time information.

各家航空公司編制內都有數十位氣象專家，儘可能協助規劃航班並指引其避免亂流，飛行員也能獲得大量的即時信息。

More than 700 aircraft, such as the 737, 757, 767, 777 and Airbus A319 and 321, are using the Weather Company’s four-year-old software program, Total Turbulence, which collects and shares data with pilots using the system.

有超過700架飛機在使用氣象公司提供的、有四年曆史的“亂流全覽”(Total Turbulance)軟件。這其中有波音737、757、767、777型，還有空中巴士A319與321型飛機。“亂流全覽”能夠收集數據，並與使用這款軟件的飛行員共享數據。

“The challenge of turbulence is that there’s no one answer to the problem,” Mr. Miller said.

米勒說：“亂流的挑戰就在於，應對這個問題沒有唯一答案。”