2022年高考英语最新热点阅读:飞机黑匣子是什么?为何叫黑匣子?外刊原文

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2024年5月21日发(作者：)

Airplane fatalities are statistically rare. When they do happen, however, they

are often fatal and people want answers as to why their loved ones lost their lives,

and that is where black boxes come into play.

What is a black box?

A black box is an electronic recording device placed in an aircraft for to

facilitate the investigation of aviation accidents and incidents.

Black boxes are actually known as flight recorders.

There are two different flight recorder devices: the flight data recorder

preserves the recent history of the flight through the recording of dozens of

parameters collected several times per second; the cockpit voice recorder (CVR)

preserves the recent history of the sounds in the cockpit, including the

conversation of the pilots.

The two devices may be combined in a single unit. A black box is the size of a

shoe box.

What does a black box do?

The flight data recorder and cockpit voice recorder are compulsory on every

commercial flight or corporate jet, and are usually kept in the tail of an aircraft,

where they are more likely to survive a crash.

FDRs record things like airspeed, altitude, vertical acceleration and fuel flow

and has about 25 hours of recording storage.

Together, the FDR and CVR objectively document the aircraft’s flight history,

which may assist in any later investigation.

The CVR records the conversation between the pilots as well as with the air

traffic control tower. The sounds of switches and engine are also recorded by the

device.

However, a cockpit video recorder can store only two hours of cockpit voice

recording.

The CVRs store the crew’s interactions with each other and air traffic control,

but also background noise that can give vital clues to investigators in case of a

crash.

How is a black box traced?

Equipped with an underwater locator beacon (ULB), if an aircraft crashes into

water, the beacon sends out an ultrasonic pulse that is detectable by sonar and

audio equipment to depths to approximately 14,000 feet.

Incredibly, the beacon is powered by a battery that has a shelf life of six years;

once the beacon begins pinging, it pings once per second for 30 days until its

battery runs out.

The black box works in depths up to 6,000 metres of saltwater.

If a plane crash takes place on land and not on water, the locator beacons of

the black box will not send out the ultrasonic pings, signalling the investigators to

look for the unit around the crash site.

Black box is not black

The term “black box” was a World War II British phrase, originating with the

development of radio, radar, and electronic navigational aids in British and Allied

combat aircraft. These often-secret electronic devices were literally encased in non-

reflective black boxes or housings, hence the name “black box”.

These black boxes are of fluorescent flame-orange in colour.

The recorders are bright orange so to make them more visually conspicuous

in the debris after an accident.

How robust are these units?

These are highly resilient pieces of kit, able to withstand extreme heat, jarring

crashes and tonnes of pressure.

Before being put into use, they are tested to see if they can withstand an

impact with a concrete wall at 750 kilometers per hour (about 466 miles / hour), a

static load of 2.25 tons for at least five minutes, a maximum temperature of 1,100

degrees Celsius (2,012 Fahrenheit) for one hour and water pressure found in depths

of up to 6,000 meters (about 19,700 feet).

Will black box be replaced?

It’s looking increasingly likely that the little black box will be replaced by

streaming all essential data directly to a ground-based station.

Air-to-ground systems can send flight data to a home base via satellite, which

help to eliminate the desperate search for a box, and saving time that might lead

to support being provided to a flight in trouble much sooner — possibly averting

a crisis.

However, satellite and GPS capacity, data storage speeds and the length of

battery life are all areas that are being developed by scientists to support new

innovations that are faster and lighter.

The challenge is the need to build the systems to manage the high volumes of

data that are needed to make it possible to track all commercial flight activity,

especially the use of satellites and data storage.

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