It is one of the most important pieces of forensic evidence after a plane crash: the so -called “Black box”
Actually, there are two of these remarkably resistant devices: the cabin voice recorder and the Flight Data Remember. And typically they are oranges, not black.
Federal researchers recovered on Friday the black boxes of the passenger plane that crashed in the Potomac River on the outskirts of Washington on Wednesday, while the authorities were still looking for similar devices in the military helicopter that also fell.
A recovered flight data recorder was in good condition and your information is expected to be downloaded shortly. The water had entered the voice recorder of the cabin, which will make it difficult to download the data. The collision killed 67 people in the most fatal American aviation disaster since 2001.
Here is an explanation of what are black boxes and what they can do:
What are black boxes?
The voice recorder of the cabin and the flight data recorder are tools that help researchers reconstruct the events that lead to a plane crash.
They are orange coloration so that they are easier to find in the remains, sometimes at the great depths of the ocean. Normally, the Cola section of an airplane is installed, which is considered the most surviving part of the aircraft, according to the NET site of the National Transport Security Board.
They are also equipped with beacons that are activated when submerged in water and can transmit from 14,000 feet depths (4,267 meters). While the battery feeding the Beacon will be reduced after approximately one month, there is no definitive useful life for data itself, NTSB researchers said Related Press in 2014.
For example, the black boxes of an Air France flight that crashed in the Atlantic Ocean in 2009 were found two years later from a depth of more than 10,000 feet, and the technicians were able to recover most of the information.
If a black box has been submerged in seawater, technicians will keep them submerged in fresh water to wash corrosive salt. If the water is filtered, the devices should be carefully dried for hours or even days using a vacuum oven to prevent memory chips from cracking.
Electronics and memory are marked and the necessary repairs are made. Chips are analyzed under a microscope.
What does the cabin voice recorder do?
The cabin voice recorder collects transmissions and radio sounds, such as the voices and noise of the pilot’s engine, according to the NET site of NTSB.
Depending on what happened, researchers can pay close attention to engine noise, stop warnings and other clicks and pops, said the NTSB. And from these sounds, researchers can often determine the engine speed and the failure of some systems.
Researchers are also listening to conversations between pilots and crew and communications with air traffic management. Experts make a meticulous transcription of voice recording, which can take up to a week.
What does the flight data recorder? The flight data registrar monitors the altitude of an airplane, speed and header, according to the NTSB. These factors are between at least 88 parameters that must monitor newly built planes.
Some can collect the state of more than 1,000 other characteristics, from the formation of a wing to smoke alarms. The NTSB said it can generate an animated video reconstruction of the flight computer from the information collected.
NTBS researchers told the AP in 2014 that a flight data recorder transports 25 hours of information, including previous flights within that period of time, which can sometimes provide suggestions on the cause of a mechanical failure on a flight later. An initial evaluation of the data is provided to the researchers within 24 hours, but the analysis will continue for more weeks.
What are the origins of the black box?
At least two people have accredited the creation of devices that record what happens in an airplane.
One is the French aviation engineer Francois Hussenot. In the 1930s, he found a way to record the speed, altitude and other parameters of a plane in the photographic film, according to the NET site of the European Airbus aircraft manufacturer.
In the 1950s, the Australian scientist David Warren occurred to him the though of the cabin’s voice recorder, according to his 2010 AP obituary.
Warren had been investigating the accident of the world’s commercial plane plane, the comet, in 1953, and thought it would be useful for airline accident investigators to have a recording of voices in the cabin, said the Department of Defense of Australia in a statement after a statement later. His death.
Warren designed and built a prototype in 1956. But several years passed before officials understood how valuable the device could be and began to install them in commercial airlines worldwide. Warren’s father had been killed in a plane crash in Australia in 1934.
Why the name ‘Black Field’?
Some have suggested that the Hussenot device is derived because he used a movie and “continuously ran in a tight box, hence the name ‘Black Field’”, according to Airbus, who said that Orange period the chosen coloration of the box from the beginning Even make it easy to find.
Other theories include the boxes that become black when they carbonize in an accident, Smithsonian magazine wrote in 2019.
“The truth is much more mundane,” the magazine wrote. “In the electronic circuit field after World War II, Black Field became the ubiquitous term for an autonomous electronic device whose entry and exit were more defining than their internal operations.”
The media continue to use the term, the magazine wrote, “due to the feeling of mystery that transmits after an air disaster.”
