韩亚失事客机是波音777首次致命事故

The crash of an Asiana Airlines aircraft marks the first fatal accident and only the second serious incident in the 18-year life of Boeing’s twin-engined 777 – one of the most popular passenger jets in the world today.

韩亚航空(Asiana Airlines)一架客机失事，标志着波音(Boeing) 777投入商业运营18年来的首次致命事故和第二起严重事故。这种双发飞机是当今世界上最受欢迎的喷气式客机之一。

It is also the first fatal crash of a commercial airliner in the US for almost five years and comes at a time when fatal crashes in the developed world are increasingly rare. Last year was the safest in terms of number of accidents since 1945 – according to the Aviation Safety Network – when commercial aviation was in its infancy and a fraction of the number of flights operated compared with today.

这也是美国近五年来首次有商业航空公司发生有乘客罹难的坠机事故，目前发达国家发生致命坠机的情况越来越少见。根据航空安全网络(Aviation Safety Network)的数据，就事故次数而言，去年是自1945年以来最安全的一年；1945年时，商业航空仍处于襁褓时期，航班数量与当今不可同日而语。

Just what caused the Asiana crash in San Francisco, which left two people dead, will take some time for investigators to establish.

究竟是什么原因导致韩亚客机在旧金山坠毁，导致两人死亡，将需要调查人员花费一段时间确定。

The 777 is a widely used long-haul airliner. Boeing says it has delivered 888 passenger variants of the jet. Among these, 421 have been the 777-200ER variant involved in Saturday’s accident.

波音777是一种广泛使用的长程客机。波音表示，至今已交付888架客机型号的777，其中421架是上周六失事的777-200ER型。

Initial reports of what happened to the aircraft as it was on its final approach to San Francisco International Airport suggest some similarities to the only other crash of a 777. In 2008, a British Airways 777-200ER crash-landed just short of the runway at London’s Heathrow airport.

有关失事客机降落旧金山国际机场时最后进场阶段情况的初步报告似乎表明，这起事故与777唯一的另一次坠机事故有一些类似之处。2008年，英国航空(British Airways)一架777-200ER曾在伦敦希思罗机场跑道外紧急降落。

Remarkably, no one was killed in that crash and a subsequent investigation revealed that ice particles had clogged the fuel system, causing both engines to fail on final approach. The problem was identified as specific to the Rolls-Royce engines that powered the BA jet and has since been fixed.

所幸那起坠机事故未导致人员丧生，随后进行的调查发现，燃料系统因结冰而堵塞，导致两台发动机均在最后进场阶段失灵。经查明，这个问题仅发生于英航客机所用的罗尔斯•罗伊斯(Rolls-Royce)发动机，而且在那之后已得到纠正。

The Asiana jet was powered by engines built by Pratt & Whitney of the US and technical experts say that no similar issues were found with those engines. A UK-led investigation into the BA crash recommended that other engine types were checked.

韩亚失事客机所用的发动机出自美国普惠公司(Pratt & Whitney)。技术专家们表示，这些发动机没有发现类似问题。由英国牵头的针对英航坠机的调查建议，对其它型号的发动机也进行检查。

Speculating about the likely causes of the crash this early into the investigation is always difficult. But Jock Lowe, a former BA director of flight operations and the world’s longest-serving Concorde pilot, said the most telling statement so far had come from the chief executive of the South Korean airline.

在调查初步阶段对坠机原因进行猜测始终是困难的。但是，英航前航班运营总监、全球服役时间最长的协和式(Concorde)超音速客机飞行员乔克•罗威(Jock Lowe)表示，迄今最说明问题的声明出自韩亚航空首席执行官之口。

“Currently we understand that there were no engine or mechanical problems,” Yoon Young-doo, Asiana chief executive, told a news conference in Seoul.

“据我们目前所知，失事前没有发动机或机械故障，”韩亚航空首席执行官尹永斗(Yoon Young-doo)在首尔举行的一场新闻发布会上表示。

The advanced systems on the jet will have provided constant feedback to Asiana engineers on the ground monitoring more than 4,000 different aircraft settings every second, according to Mr Lowe.

据罗威介绍，飞机上的先进系统会每秒监测逾4000项飞机运行参数，并向韩亚的地面工程技术人员持续提供反馈。

“Although the Asiana crash looks very similar to the BA incident at Heathrow there are two big differences,” said Mr Lowe. “Firstly, the aircraft had Pratt & Whitney engines, and secondly the airline has said there were no problems with them.”

“虽然韩亚此次坠机看上去很像英航在希思罗发生的事故，但实际上有两大不同点，”罗威表示。“首先，这架飞机配备的是普惠发动机，其次，航空公司已表示，这些发动机没有问题。”

Mr Lowe said that in the immediate aftermath of the BA crash, the pilots who had nursed the aircraft on to the ground, had immediately pointed a finger at the engines.

罗威称，英航发生坠机后，勉强驾驶飞机着陆的飞行员立即指出发动机有问题。

The Asiana pilots will similarly be able to help crash investigators. They were among the survivors of the 291 passengers and 17 crew on board. The two people killed were reported to be Chinese nationals sitting at the back of the aircraft.

韩亚航空的飞行员也将同样能够协助坠机调查。机上291名乘客和17名机组人员生还，飞行员也在生还者之列。两名罹难者据报道是坐在飞机后排的中国公民。

Mr Lowe said the most likely two causes of the crash were problems with the aircraft’s flight control surfaces, which might have been harder to pick up immediately, or pilot error.

罗威表示，此次坠机的两大可能原因是飞机的飞行操纵装置有问题（此类问题可能不易马上发现）或者飞行员失误。

The Asiana aircraft was reported to have been flying far too slowly on approach. It was reportedly flying at an air speed of 98 knots. Normal approach speed is between 135 and 140 knots.

有报道称，失事的韩亚客机在进场时速度过低。当时其空速据报道只有每小时98海里，而正常的进场时速应当在135至140海里之间。