马航飞机失联：飞行中可能会遇到的问题

There's always a risk in flying, but the phase in which a plane is cruising at high altitude is widely considered to be safe. And that's what makes the mystery of what happened to so confounding.
飞行总是存在风险，但人们普遍认为飞机在较高的高度巡航的阶段是安全的。因此马航MH370的失联才如此让人迷惑。

"Whatever happened happened quickly and resulted in a catastrophic departure from the air," Mark Rosenker, former chairman of the National Transportation Safety Board who is now a consultant with CBS news, told NPR's Melissa Block.
美国国家运输安全委员会的前任主席马克·罗森克目前是CBS新闻的一名顾问，他对NPR的梅丽莎·布洛克表示，“不论发生了什么，一定是在瞬间发生，并且导致了飞机在空中发生了灾难性的事故”。

There have been a number of cases in which planes have fallen from the sky — from factors that include catastrophic failure and sabotage. As Patrick Smith, a commercial pilot who runs the popular:
飞机从空中坠落曾经有一些案例，原因包括严重故障和遭到蓄意破坏。民航飞行员帕特里克·史密斯的分析获得了广泛认同：

"All we know for sure is that a plane went down with no warning or communication from the crew. That the crash did not happen during takeoff or landing — the phases of flight when most accidents occur — somewhat limits the possibilities, but numerous possibilities remain. The culprit could be anything from sabotage to an in-flight fire to a catastrophic structural failure of some kind — or, as is so common in airline catastrophes, some combination or compounding of human error and/or mechanical malfunction."
“我们现在唯一清楚的就是飞机没有发出任何警报或通信就发生了事故。而这个事故并没有发生在起飞或降落的时候，这两个阶段是大部分航空事故发生的阶段，所以可能性减少了，但依然存在许多可能。罪魁祸首可能是蓄意破坏，也可能是飞机起火，也可能是重大的结构损坏，或者是许多空难当中的原因，即人为失误加上机械故障。”

Here are some of the problems an aircraft can experience during flight:
飞机在飞行途中可能会遇到下列问题：

Stresses
压力

An aircraft undergoes two kinds of routine stresses: a mechanical stress on the cabin caused by the pressurization and depressurization cycle that happens on each flight; and stress on the plane when it lands.
一架飞机会承受两种必有的压力：一是每架飞机中的增压降低的循环导致的机舱机械应力，二是飞机落地时的压力。

The structural fatigue and damage they cause "are typically taken care of by periodic maintenance," Todd Curtis, an aviation safety analyst who now runs the AirSafe.com Foundation, said in an email.
由压力导致的飞机结构性疲劳和损失“一般都通过定期维护来解决”，航空安全分析员托德·柯蒂斯在一封电子邮件中说，他现在运营着航空安全基金会。

The Malaysian Airlines Boeing 777 was last inspected just 10 days ago and was said to be in proper condition. The 777 is a long-haul aircraft that is regarded as safe. , it's had about 60 incidents since it entered service in 1995.
这家马航波音777飞机在10天前刚刚检查过，而且据称状况良好。波音777是一种远程飞机，普遍认为安全性很高。从1995年投入使用以来只发生过60次事故。

Takeoff and landing are typically the riskiest portions of the flight. A Boeing 777 operated by Asiana Airlines was involved in the crash at San Francisco Airport last year that killed three people.
起飞和降落通常是飞行过程中最危险的两个时段。一家韩亚航空的波音777去年在旧金山机场降落时就发生了事故，造成3人死亡。

But the en-route portion of the flight, which the Malaysian Airlines flight was on, is seen as the safest. According to a Boeing analysis, only 9 percent of fatal accidents occur at cruising altitude.
但在飞行途中，也就是马航飞机失联的时段，普遍认为是最安全的。根据一份波音公司的分析，只有9%的致命事故发生在巡航高度。

"Cruise is generally a pretty good place," says David Ison, assistant professor at Embry-Riddle Aeronautical University, who was a transport pilot with international and transoceanic experience. "There's stable conditions. The weather at higher altitudes is generally better. The only issue is turbulence and sometimes thunderstorm activity."
埃姆伯里-利德尔航空学院的助理教授大卫·艾森说，“巡航通常是一个非常不错的阶段”。艾森曾经是一名运输机飞行员，有过国际以及跨洋飞行的经历。“这个阶段条件很稳定。高度越高，天气状况通常越好。唯一的问题是气流，偶尔会有雷暴活动。”

Weather
天气

While weather is a factor at higher altitudes, Flight MH370 was traveling in good weather conditions.
虽然在较高的高度飞行时天气也是需要考虑的因素，但是MH370航班当时的天气状况很好。

Referring to the Malaysian Airlines flight, Curtis said:
关于马航失联航班，柯蒂斯说：

"Weather can be a factor, but it is unclear if it was a factor in this event. One factor that was happening during this event was that the aircraft is flying over the ocean at night. Under these visual conditions, the crew may not be able to look out the window and use the horizon as a sort of backup aircraft altitude indicator. This may make it harder for the pilots to recover the aircraft if it gets into an unusual attitude."
“天气会有影响，但在这次事件中还不清楚这是否是其中一个因素。这次事件有一点，飞机当时是在夜间在海洋上空飞行。在这种视觉条件下，飞行员也许无法看清窗外，利用地平线作为飞机高度的参考。这样一旦飞机的高度出现异常，飞行员想要做出调整难度就会加大。”

Technical/Catastrophic Failure
严重的技术故障

Catastrophic failure can affect one or more critical aircraft structures or systems, making it difficult or impossible for the crew to safely land the aircraft.
严重的故障可能会对一处或多处飞机结构或系统造成影响，从而导致飞行员难以甚至无法让飞机安全降落。

There are exceptions to this, of course. The most famous being the "miracle on the Hudson" in 2009, when U.S. Airways Flight 1549 took off from LaGuardia Airport in New York, struck some birds on its way into the sky, lost both engines and was then successfully guided to a safe landing.
当然也有例外。最著名的一次是2009年的“哈德逊河奇迹”，一家全美航空1549航班从纽约的拉瓜迪亚机场起飞，升空后遭遇鸟击，双引擎失灵，最终依然成功平安降落。

Curtis says, "Because many aircraft systems have backup systems or backup procedures, it usually takes multiple failures to occur before those failures are considered catastrophic or potentially catastrophic."
柯蒂斯说，“因为很多飞机系统都有后备系统或后备程序，如果发生严重的毁灭性的故障，那么一定是发生了多重故障。”

One example of this is Air France Flight 447 that crashed over the Atlantic in 2009. An accident report blamed faulty air speed sensors and pilot error for the crash that killed 228 people.
比如2009年在大西洋坠毁的法航447航班。事故调查报告认为，飞行速度传感器和飞行员操作失误共同导致了这次造成228人死亡的空难。

Ison of Embry-Riddle notes that aircraft today are so reliable that technical failures are highly unlikely in regular operations. In 75 percent to 80 percent of such cases, he notes, the error is human — either by the pilot or by air traffic controllers.
埃姆伯里-利德尔航空学院的艾森认为，今天的飞机都非常可靠，正常操作下不太可能出现技术故障。他认为75%-80%的飞行事故都是人为原因造成的，要么是飞行员的失误，要么是空中交通管理员的失误。

Sabotage
蓄意破坏

Sabotage is the single-biggest reason for en-route accidents, writes Max Kingsley-Jones, a reporter for Flight Global, an aviation magazine.
飞行途中发生的事故，蓄意破坏是最大的原因。一家航空杂志《环球飞行》的记者马克思·金斯利琼斯在报道中这样写。