[Beijing at 1:20 on March 8 from Kuala Lumpur to Beijing，Malaysia Airlines MH370 flight lost contact with the ground. There were 239 people on board, including 153 Chinese passengers. Beijing at 22:00, March 24, Malaysian Prime Minister Najib held a news conference to announce the aircraft in the South Pacific "The End."What happened about the “lost contact “in this Boeing 777-200? What is the truth of this incident? For now, finding the black box is opened Malaysia lost contact with flight only hope. So, what is the black box in the end? How does it work? After the crash, how did it work?
Understanding: What is the Black Box?
Black box, full name is the flight data recorder; it was used to record all information and details of the aircraft during flight. Modern aircraft generally installed two black boxes; one is the "cockpit voice recorder," the other is "flight data recorder." The former is used to record the pilot cockpit and cabin, cockpit between the pilot and the passenger's speech recording, and all voice heard. "Flight data recorder" records the flight parameters, such as the horizontal speed, vertical speed, acceleration as well as magnetic angle of flight data.Although the black box is called "black”, but is really orange-red. Black Box is length of about 40 cm, width and height of 20 cm, rectangular shape. Each weighs about 20-30 kilograms.
Principle: How to Work
Black box generally be installed in the plane's tail, because the tail of the plane crash, usually intact. Underwater signal black box comes with its own identifier, once falling into the water, it automatically activates the battery-powered systems, uninterruptible emission frequency of 37.5 kHz waves, that is useful for searchers to confirm its position.
Performance: mandatory standard of the Black Box
According to International rules and regulations, from falling into the water to run out of battery, black boxes transmit signals must be guaranteed for at least 30 days. The battery power of the black box is different, but also it must issue 15 days or more noise to help people search to it.
Difficulties: positioning of the Black Box
In the ocean, the hardest part is to determine the exact position of the aircraft crashed. Battery runs out before the black box, while black box's signal cannot be downloaded, searchers need to use sonar system suspected of bottom waters; analysis echoes draw undersea graphics work. Through graphics, rescuers were on the waters of any unusual or non-conventional morphology, detection the Sonar, and then by the miniature unmanned submarine dive, scan abnormal area to determine whether it is the fact that the aircraft wreckage.
Everyone wants: to find the black box MH370
After Malaysia Airlines Flight 370 “lost contact" on March 8th, some countries have started to search the black box. The U.S. military provided the name "Ocean Shield" number and "Echo" towed underwater sonar, it the deepest can "hear" the signals emitted by the black box from about 6096 meters underwater; Australia “Ocean Shield" supply ship and British "Navy's "tracking ship were also used to search ; China sent " Coast Guard 01 "with portable instrument to search the black box , it can find the acoustic underwater locator beacon within the range of 3000-5000 m .All these hope to determine the crashed aircraft location according the sound strength of black box. Black box emits electromagnetic waves; this is the way to communicate with people. Some international experts’ worry that 37.5 kHz is not exclusive for black box, some underwater locating device also uses it, which makes people difficulties to find out the black box.