The US and UK are banning laptops from cabin baggage on flights from certain countries in the Middle East and North Africa, as well as Turkey.
美英两国正对由中东、北非地区某些国家及土耳其入境的航班实施禁止随身携带笔记本电脑登机的禁令。
The US ban on electronic devices larger than a smartphone is being imposed as an anti-terrorist precaution.
美国禁止随身携带大于智能手机的电子设备登机的禁令是为了防范恐怖袭击。
The US ban applies to 10 airports in eight Muslim-majority countries. It covers inbound flights on nine airlines. Phones are not affected.
该禁令针对8个穆斯林为主要人口国家的10座机场，涉及9家航空公司的入境航班。手机不受影响。
The British ban, announced hours after the American measure, is similar but applies to different airlines.
几小时后，英国紧随美国公布了类似的禁令，但是涉及的航空公司不同。
Downing Street said airline passengers on 14 carriers would not be able to carry laptops in cabin luggage on inbound direct flights from Turkey, Lebanon, Jordan, Egypt, Tunisia and Saudi Arabia.
英国政府表示，乘坐14家航空公司从土耳其、黎巴嫩、约旦、埃及、突尼斯以及沙特阿拉伯直飞英国入境航班的乘客将无法随身携带笔记本电脑。
The Turkish government said the US ban was wrong and should be reversed.
土耳其政府称，美国的禁令是个错误，应该被撤销。
Large electronic devices will still be allowed on board in checked baggage.
大型电子设备仍然可以托运带上飞机。
Canadian Transport Minister Marc Garneau said his country was also considering restrictions on electronics in the cabins of planes.
加拿大交通部长马克•加尼奥称，加拿大也在考虑限制飞机客舱内的电子产品。
Which flights are affected?
哪些航班受到影响？
The nine airlines affected by the US ban:
受美国禁令影响的9家航空公司：
Royal Jordanian, EgyptAir, Turkish Airlines, Saudi Arabian Airlines, Kuwait Airways, Royal Air Maroc, Qatar Airways, Emirates, Etihad Airways
皇家约旦航空、埃及航空、土耳其航空、沙特航空、科威特航空、摩洛哥皇家航空、卡塔尔航空、阿联酋航空以及阿提哈德航空。
The 14 Carriers affected by the UK ban:
受英国禁令影响的14家航空公司：
British Airways, EasyJet, Jet2.com, Monarch, Thomas Cook Airlines, Thomson Airways, Turkish Airlines, Pegasus Airways, Atlas-Global Airlines, Middle East Airlines, EgyptAir, Royal Jordanian, Tunis Air, Saudi Arabian Airlines
英国航空，易捷航空，Jet2.com，君主航空，托马斯库克航空，汤姆森航空，土耳其航空，天马航空，阿特拉斯环球航空，中东航空，埃及航空，皇家约旦航空，突尼斯航空，沙特航空
The airlines included in the US decision have been given a deadline of 07:00 GMT on Saturday to impose the ban, officials said, adding that the restriction had no end date.
美国政府官员称，接到该国指令的航空公司需在25日格林尼治时间7点前执行禁令，并称该禁令没有截止日期。
However, an Emirates spokeswoman told Reuters news agency the airline understood that the US directive would come into effect on 25 March and remain valid until 14 October 2017.
然而，阿联酋航空的一位发言人告诉路透社，该公司获悉美国的禁令将于3月25日生效，执行至今年10月14日。
Why now?
为什么在此时推出禁令？
The restriction is based, we are told, on "evaluated intelligence", BBC security correspondent Frank Gardner writes.
BBC安全事务通讯员弗兰克•加德纳称，BBC被告知这项禁令基于“已经过评估的情报”。
That means that US intelligence has either intercepted discussion of a possible extremist plot or has been passed word of one by a human informant.
这意味着美国情报部门要么截获了一则潜在的极端主义阴谋情报，要么有线人向其传递了消息。
The Middle Eastern and North African airports affected are nearly all ones with close, friendly relations with Washington, so this will be seen by some as a drastic and unpopular measure. Wealthy Gulf Arab business leaders flying to the US, for example, will no longer be able to work on their laptops mid-flight.
中东、北非地区受影响的机场几乎都与美国保有密切友好的关系，所以一些人认为此项禁令是激进而不得人心的措施。富有的波斯湾地区商业领袖在飞往美国途中再也不能使用笔记本电脑办公了。
But aviation security experts were alarmed by an incident in Somalia last year when the insurgent group al-Shabaab smuggled an explosive-filled laptop on a flight out of Mogadishu, blowing a hole in the side of the plane. The aircraft was still low enough that the pilot was able to land the plane safely.
去年索马里发生的一起事件让航空安全专家们惊恐万分。当时武装组织索马里青年党将一台装满爆炸物的笔记本电脑偷偷带上了摩加迪沙的离港航班，将飞机一侧炸开了一个窟窿。由于飞机还在低海拔飞行，飞行员才得以安全降落。
How is the ban being justified?
禁令是否正当合理？
In a statement, the DHS cited attacks on planes and airports over the past two years.
美国国土安全部在一份声明中援引了过去两年针对飞机和机场的袭击。
Bombs, it said, had been hidden in such items as a soft drink can, in the downing of a Russian airliner over Egypt in October 2015 with the loss of 224 lives, and the laptop used in the unsuccessful Somali attack last year.
国土安全部表示，2015年10月一架俄罗斯客机在埃及上空爆炸坠落，炸弹藏在了软饮料罐中。去年，有人利用笔记本电脑策划索马里袭击未遂。
"Evaluated intelligence indicates that terrorist groups continue to target commercial aviation, to include smuggling explosive devices in various consumer items," the DHS said.
“情报评估表明，恐怖组织一直把民用航空作为攻击目标，利用各种各样的消费品将爆炸装置偷运上飞机。”
A British Government spokesperson said: "The additional security measures may cause some disruption for passengers and flights, and we understand the frustration that will cause, but our top priority will always be to maintain the safety of British nationals."
英国政府的一位发言人表示：“这项附加的安全措施可能会对乘客和航班造成一定困扰。我们完全理解因此引发的不满。但是我们始终将维护英国公民安全作为第一要务。”
Will the ban be effective?
禁令有用吗？
Turkish Transport Minister Ahmet Arslan told reporters the ban was "not a right move".
土耳其交通部部长艾哈迈德•阿尔斯兰告诉记者，禁令“不是恰当的措施”。
"We particularly emphasise how this will not benefit the passenger and that reverse steps or a softening should be adopted," he added.
他说：“我们特别强调，这样做将对乘客不利，应该将禁令取消或采取温和措施。”
Philip Baum, editor in chief of Aviation Security magazine, told the BBC: "If we cannot, in 2017, distinguish between a laptop that contains an IED (improvised explosive device) and one that does not, then our screening process is completely flawed.
《航空安全》杂志主编菲利普•鲍姆对BBC表示：“如果我们现在还不能区分含有临时爆炸装置的笔记本电脑和普通的电脑，那么这说明我们的审查程序存在缺陷。”
"And encouraging people to check laptops, and other such items, into the luggage hold simply makes the challenge even harder. Cabin baggage can, at least, be inspected piece by piece and the accompanying passenger questioned."
“鼓励人们托运笔记本电脑以及其他电子产品只会让挑战难上加难。至少，随身行李可以一件件检查，也可以对行李携带者进行盘问。”
Simon Calder, travel editor of the UK's Independent newspaper, suggested the British ban would affect travellers differently because it included budget flights.
英国《独立报》的旅行编辑西蒙•考尔德认为，该国禁令会对旅行者产生不同的影响，因为禁令也涉及廉价航班。
"It's easy for the Americans, they don't have as many flights as us coming in and furthermore they don't have things like low-cost flights where I'm not going to pay to check in a bag," he told the BBC.
他对BBC称：“这对美国人来说很简单，他们的入境航班不像我们这么多，此外，他们没有廉价航班，我搭乘这类航班时不会付费托运行李。”
"And suddenly I've got my laptop, I'm going to have to put that in a little bag and hand it in. Oh, and by the way, good news for petty thieves all over the airports of the world because lots of rich pickings are going to be around."
“而现在突然要托运笔记本电脑，我要把它放进小行李袋里交上去。哦，顺便说一下，这对于各国机场的众多小偷来说是个好消息，因为很多值钱的东西等着他们大显身手。”