时代周刊:无人机泛滥引来安全威胁(3)（在线收听）

In the first nine months of 2017 there were 1,696 drone sightings, according to the FAA’s most recent data,

联邦航空局（FAA）最新数据显示，2017年前9个月，飞行员们就目睹了1696起无人机违章飞行事件，

compared with 238 in all of 2014, the first year the data were tracked.

而首次追踪这一数据的2014年全年数据才238起。

The FAA expects the problem will get worse as the number of drones is estimated to triple to 3.5 million by 2021.

该局预计，到2021年，无人机数量还会上涨两倍，达到350万架，届时问题将会更加严重。

The risk of small drones’ flying into sensitive facilities first came into public view in 2015

小型无人机飞入敏感设施的风险首次进入公众视野是在2015年，

when a hobbyist lost control of a drone that crashed on the southeast side of the 18-acre secure zone around White House grounds at about 3 a.m.,

那年某日凌晨3点左右，一名无人机爱好者的无人机失去控制，飞入白宫附近方圆18英亩的安全区东南侧坠毁，

triggering a Secret Service lockdown of the compound.

引发了特勤局对该区域的封锁。

Drones are off-limits in the airspace in the 15-mile radius around Washington

距离华盛顿方圆15英里的空域都是无人机禁飞区，

and also over places like the Hoover Dam, the Statue of Liberty and Mount Rushmore.

胡佛大坝、自由女神像和拉什莫尔山也是如此。

The drone that crashed near the White House, called a DJI Phantom, caused no damage, but it flew in undetected.

于白宫附近坠毁的无人机名为“大疆幻影”，虽未造成任何破坏，问题是该无人机飞入了禁飞区都未被发现。

That highlights one of the greatest challenges to tracking and countering drones deployed by bad actors.

这一问题也彰显了追踪和打击心怀不轨之人部署的无人机所需面临的一大挑战。

Existing radar systems are designed to detect much bigger threats.

由于现有雷达系统的目标是探测体型比无人机大得多的威胁。

Most commercial drones are constructed of plastic and are difficult to spot electronically

而大多数商用无人机的材质都是塑料，加上电子设备很难识别——

because they’re small, fly low to the ground and don’t carry a transponder to signal their positions.

无人机体型很小，贴近地面飞行，加之没有携带会暴露它们位置的应答器。

“It’s only a matter of time before the threat manifests in a violent way,” Defense Secretary James Mattis told a Senate panel in May.

今年5月，国防部长詹姆斯·马蒂斯在参议院的一个小组会议上表示：“无人机造成严重安全威胁只是时间问题。”

The military has already faced the drone danger abroad.

在国外，美国军方已经遭遇无人机威胁。

As American Special Operations commandos fought to retake the Iraqi city of Mosul from ISIS in the fall of 2016,

2016年秋季，美国特种作战突击队试图从ISIS手中夺回伊拉克城市摩苏尔时，

they faced a threat that American ground forces hadn’t dealt with: attack from the air.

就遭遇了美国地面部队从未遭遇过的威胁：来自空中的攻击。

Desperate to break the American-led siege of the city, ISIS militants sent fleets of small drones,

当时，ISIS武装分子不顾一切地想要打破美国主导的对这座城市的包围，便派出了由小型无人机组成的舰队，

often several at a time, carrying grenades and miniaturized explosives, scattering troops and driving them to seek cover.

通常一次性派出数架携带有手榴弹和小型炸药的无人机来分散美方力量，迫使美方寻找掩护。

“At one point there were 12 killer bees, if you will, right overhead,”

“曾经有一次头顶多达12只杀人蜂，”

General Raymond Thomas, head of Special Operations Command, said last year,

去年，特种作战司令部司令雷蒙德·托马斯将军说，

adding that the fighting nearly came to a “screeching halt.”

他还说，战斗几乎“戛然而止”。

The drones were too small for a fighter pilot or a tank gunner to pursue,

那些无人机体型过小，战斗机飞行员或坦克炮手根本无法追击，

which meant the troops’ only defense was to try to shoot the aircraft out of the sky with their rifles.

这就意味着军队唯一的办法就是用步枪将其从空中击落。

Thomas said the small drones were the “most daunting” threat his commandos faced during the house-to-house campaign in Mosul.

托马斯还说，他的突击队员在摩苏尔挨家挨户展开行动时，小型无人机是他们面临的“最令人畏惧”的威胁。

No U.S. casualties were reported.

然未出现有关美国人员伤亡的报道。

No American forces have been killed by an air attack since the Korean War.

自朝鲜战争以来，美国军队还未因为空中袭击出现伤亡。