科普：飞机起降时为什么需要关闭客舱灯？

At this point,pre-flight preparations are routine.
如今 飞行前准备是例行公事
Prior to takeoff, we’ll need all baggage to be stowed properly.
起飞前 我们需要妥善放置所有行李
Your seats move to the upright position and your seat belts securely fastened.
调直座椅靠背并系好安全带
Thank you.
谢谢
Once everyone’s set, the plane lurches away from the terminal
一切准备就绪 飞机就会离开航站楼
and the lights inside the cabin go out.
机舱内的灯也会关闭
It happens without mention.
且没有任何提醒
You may not have even fully noticed that it does happen.
你可能还没有完全注意到 它就发生了
One reason has to do with what’s called the 90 second rule.
这么做的原因之一是所谓的“黄金90秒”原则
It’s a guideline that dictates
这是一个指导方针
many of the mundane, but absolutely crucial in-flight procedures.
它规定了一些平凡却至关重要的飞行程序
In the 1920’s,
在20世纪20年代
the pre-flight routines we now know by heart were non-existent.
我们现在熟知的飞行前程序是不存在的
Basically, pilots would tell passengers to put on a parachute
基本上 飞行员会告诉乘客穿上降落伞
and briefly show them how to use it.
并简要告诉他们使用方法
During that time,
在那段时间里
commercial air traffic saw a death for every 13,500 miles flown.
商业航空运输中 每飞行13500英里就有1人死亡

It’s not good.
这很糟糕
But there was one airline that
但有一家航空公司的表现
performed much better than the industry median.
远远好过行业平均水平
That was the government-owned air mail system
那就是政府拥有的航空邮件系统
and it was run with an eye on safety.
它在运行时考虑到了安全问题
Pilots were selected after careful medical examinations.
飞行员是经过仔细的体检后挑选出来的
Engines were checked once every 100 hours of flight time.
每飞行100小时 人们就要检查发动机
And after every single flight,
并且每次飞行后
there was a 180-point Inspection Checklist.
都要执行一份包含180个要点的检查单
Because of that thoroughness,
由于检查的彻底性
the air mail system
航空邮件系统中
saw a fatality for every 789,000 miles flown.
每飞行789000英里才有1人死亡
The industry took notice and things started to change.
业界注意到了这一点 航空业开始发生改变
By 1935, the Aeronautics Branch, now called the Bureau of Air Commerce
1935年 航空部门 即现在的航空商务局
had a list of new safety regulations.
制定了一份新的安全条例清单
Some of those new rules for planes
其中有一些新的规定
were the requirement of co-pilots, two way radios,
如飞机上要配备副驾驶 双向无线电
limits on the hours pilots can be in the air,
限制飞行员的飞行时间
and that planes needed to have multiple engines,
以及给飞机装上多个发动机
get the ability to fly
以便出现紧急状况时
on one engine in the case of an emergency.
飞机可以依靠单个发动机飞行
By 1937, the number of pilots increased from 1927 by 700 times.
到1937年 飞行员人数比1927年增加了700倍
Meanwhile, deaths went down 10 times over that same time period.
与此同时 空难死亡人数在同一时期下降了10倍
In 1967, the Bureau of Air Commerce became the Federal Aviation Administration.
1967年 航空商务局成为联邦航空管理局
Soon after, they required all airlines to include
随后 他们要求所有航空公司配备
oxygen masks, flotation devices,
氧气面罩 救生衣
and emergency exit markings
以及紧急出口标志
making it clear to passengers where the closest exits are.
以便让乘客知晓最近的紧急出口在哪里
All part of what’s called the 90 second rule.
以上都是“黄金90秒”的规定
The 90 second rule requires airlines
“黄金90秒”原则要求航空公司
using planes with a capacity of 44 people or more
使用可搭载44人以上的飞机
to be able to demonstrate the ability
以证明他们有在90秒
to conduct an emergency evacuation in 90 seconds or less.
或更短的时间内进行紧急疏散的能力
Even if half the exits are blocked.
就算有一半的出口被封锁
Even today airlines have to run tests
即使在今天 航空公司也要经过测试
to prove to the FAA that they comply.
向联邦航空管理局证明他们符合要求
The Discovery Channel filmed a 90 second test for an Airbus A 380.
探索频道拍摄了空客A380的90秒测试
It’s dramatic stuff.
那是很戏剧性的场面
Believe it or not,
信不信由你
one of the major hurdles to being successful in the 90 second rule
“黄金90秒”成功的主要障碍之一
is people trying to grab their belongings to take with them.
是那些试图拿走自己行李的人
Leave your stuff.
留下你的行李
So, that leads to our initial question.
那么 回到了我们最初的问题
Why do planes turn off their lights within the cabin at takeoff and landing?
为什么飞机在起降时 客舱内的灯会关闭？
The lights inside the cabin are turned off because of
关闭客舱内的灯是因为
the time it takes for eyes to adjust to the dark.
眼睛适应黑暗需要时间
If an emergency during takeoff or landing caused the lights
如果在起飞和降落期间突发紧急状况
to suddenly go out,
导致灯突然熄灭
no one’s eyes would be adjusted making it harder to evacuate,
人们的眼睛无法适应黑暗 这使疏散更有难度
especially in 90 seconds.
特别是在90秒之内
The retina at the back of the eye has two kinds of cells,
眼睛后部的视网膜有两种细胞
rods and cones, which take light
杆状细胞和锥状细胞
in turning them into neural signals.
它们接收光并将其转化为神经信号
The cones help when it’s light out
夜间 椎状细胞能起到帮助作用
and rods handle seeing at night.
杆状细胞能处理夜间的视线
When the lights go out, the cones adjust faster within nine to 10 minutes.
灯熄灭时 椎状细胞会在9至10分钟内快速调整
While the rods whose job it is to handle low light can take as long
然而处理较暗光线的杆状细胞
as 30 minutes to see as well as they’ll be able to.
需要30分钟才能看清东西
There’s a good reason
这很好地解释了
why the lights are turned off specifically at takeoff and landing.
为什么飞机起飞和降落时要关灯
That’s when most plane accidents occur,
事故多发生在起飞和降落期间
Boeing looked into accidents that led to
波音公司调查了2006至2017年
fatalities from 2006-2017.
导致死亡的空难事故
They found that 13 percent happened within the first three minutes of the flight,
他们发现13%的事故发生在起飞后的三分钟
which is takeoff in the initial climb.
也就是在最开始的爬升阶段
While 48 percent of accidents that caused fatalities happened during the final descent
而致死的事故中有48%发生在落地前的8分钟
and landing ,which are the last eight minutes of the flight.
也就是飞机下降并准备着陆的时候
Along with the lights being dimmed,
随着灯光变暗
the whole pre-flight routine is providing passengers
整个飞行前的例行程序
with the directions to get to safety as fast as possible.
为乘客尽快到达安全地带指明了方向
The only thing that the 90 second rule can’t plan and test for
“黄金90秒”原则唯一不能计划和测试的
is that during an emergency, people are going to panic.
就是在紧急情况下 人们会惊慌失措
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