Introduction
flight recorder is commonly referred to as the "black box", which recorded information is mainly used for accident analysis, maintenance, flight test flight recorder is commonly referred to as the "black box", which recorded information is mainly used for accident analysis, maintenance, flight test . in many countries in the world, makes provision for civil aviation aircraft accidents must be installed for the analysis of the flight recorder may record it in many countries in the world, makes provision for civil aviation aircraft accidents must be installed for the analysis of the flight recorder may record it .
plane crash within 30 minutes prior to the aircraft altitude, speed, heading, pitch attitude, the in - line dialogue and the time data and the like, in order to analyze the reason of accident so as to provide the basis for the plane crash within 30 minutes prior to the aircraft altitude, speed, heading, pitch attitude, the in - line dialogue and the time data and the like, in order to analyze the reason of accident so as to provide the basis for the . for condition - based maintenance (CBM),Flight test of the recorder according to the task requirements and aircraft type for condition - based maintenance (CBM),Flight test of the recorder according to the task requirements and aircraft type .
flight test aircraft is developed in the research of the theory and the important t flight test aircraft is developed in the research of the theory and the important t . in flight test except for the part of the data by radio telemetry back to earth, with a flight recorder to record, analyze and evaluate the study in flight test except for the part of the data by radio telemetry back to earth, with a flight recorder to record, analyze and evaluate the study .
1 after air disasters, aircraft often disintegrate, even raging fire burned 1 after air disasters, aircraft often disintegrate, even raging fire burned . to - the - spot rescue to the people, always be looking for one thing, its name is celebrated as the "witness" of the black box to - the - spot rescue to the people, always be looking for one thing, its name is celebrated as the "witness" of the black box .
it can give investigators to provide evidence to help them understand the truth of the accident actually it can give investigators to provide evidence to help them understand the truth of the accident actually ., black box is on the plane of the recording instrument,, black box is on the plane of the recording instrument,.
it is a flight data recorder of the aircraft altitude, speed, heading, rate of climb, descent rate, acceleration, gas mileage, retractable landing gear, Greenwich time, the aircraft system status and engine operating parameters such as the flight parameter record almost it is a flight data recorder of the aircraft altitude, speed, heading, rate of climb, descent rate, acceleration, gas mileage, retractable landing gear, Greenwich time, the aircraft system status and engine operating parameters such as the flight parameter record almost . and the other is the cockpit voice recorder, and the other is the cockpit voice recorder, .
it is, as a matter of fact, it is, as a matter of fact, . radio talk recorder in order to withstand the crash of a violent impact and high temperature flames, while the black box of the housing has a very thick steel plate and a plurality of layers of heat insulation anti - impact protective material radio talk recorder in order to withstand the crash of a violent impact and high temperature flames, while the black box of the housing has a very thick steel plate and a plurality of layers of heat insulation anti - impact protective material .
And to be as secure as possible, the black box, typically mounted in the plane's tail was the most secure site,- was the most easily damaged when the wreck site of the crash, the black box of 1100.d egree. C. in a flame can withstand 30 minutes of grilling, can withstand 2 tons of extruded objects 5 minutes can be gasoline, oil, refined oil, battery acid, and subsequently marinated in seawater for several months, in a word, it can in many harsh conditions were safe and sound , even in the absence of such safeguards, some still in the black box was damaged in the crash, so the international mechanism turn - round of more stringent standards, but also from the tape - type recording medium and to improve the ability to withstand larger shocks of static memory recorder, similar to the computer memory chip , even in the absence of such safeguards, some still in the black box was damaged in the crash, so the international mechanism turn - round of more stringent standards, but also from the tape - type recording medium and to improve the ability to withstand larger shocks of static memory recorder, similar to the computer memory chip .
A Historical Survey
"Black Box" is a Melbourne engineer in 1958 invented "Black Box" is a Melbourne engineer in 1958 invented . in 1908, with the U.S. in its first military aircraft accident
thereafter, based on flight accidents have occurred, there is a need for a recall, the accident process causes the instrument thereafter, based on flight accidents have occurred, there is a need for a recall, the accident process causes the instrument . during World War II, the flight instruments in the recording equipment in aircraft applications, and later used by civilian aircraft on the flight recorder during World War II, the flight instruments in the recording equipment in aircraft applications, and later used by civilian aircraft on the flight recorder .
was called a "black box" dates back to 1954, when the aircraft within all of the electronics are placed in a size, shape, and the uniform of all black cube in was called a "black box" dates back to 1954, when the aircraft within all of the electronics are placed in a size, shape, and the uniform of all black cube in . due to modern electronic technology rapid development, in this case an aircraft,People began to advocate direct to the ground through the wireless transmission of data signals and to record, and no longer use the flight recorder, the name of the black box will be returned to the ground, e.g., a car black box data
. in 1987, a military plane exploded over Norway, aircraft crashes, pilot killed in 1987, a military plane exploded over Norway, aircraft crashes, pilot killed .
Norwegian authorities to the accident scene, from the wreckage and the body of the pilot, recognise a Soviet - era military reconnaissance aircraft of the Soviet Union to protest Norway Norwegian authorities to the accident scene, from the wreckage and the body of the pilot, recognise a Soviet - era military reconnaissance aircraft of the Soviet Union to protest Norway ., , .
later denied the former Soviet Union, Norway to find on the black box flight recorders from the black box recording to analyse the data, later denied the former Soviet Union, Norway to find on the black box flight recorders from the black box recording to analyse the data,. revealed the truth of the former Soviet Union in the face of evidence had to eat humble pie revealed the truth of the former Soviet Union in the face of evidence had to eat humble pie .
black box appearance is not black, but orange, surface also has convenient night - vision of retro - reflective markings black box appearance is not black, but orange, surface also has convenient night - vision of retro - reflective markings . because FDR (flight data recorder records the data by using special equipment and playback of downloaded software, and interpretation and analysis, plus the accident data recorder stores the very critical and mysterious, plus some accident recorder in a flame that had been turned black, and it will be referred to as FDR (flight data recorder "black box" because FDR (flight data recorder records the data by using special equipment and playback of downloaded software, and interpretation and analysis, plus the accident data recorder stores the very critical and mysterious, plus some accident recorder in a flame that had been turned black, and it will be referred to as FDR (flight data recorder "black box" .
aircraft is energized, the black box will automatically start to work, recording the relevant aircraft system and the operation state information,Flight operation personnel - related information and audio information, and personnel are not subject to control in accordance with airline requirements aircraft is energized, the black box will automatically start to work, recording the relevant aircraft system and the operation state information,Flight operation personnel - related information and audio information, and personnel are not subject to control in accordance with airline requirements ., black box data information is acquired in real - time aircraft sensors and related systems, must be retained before power - off is at least 25 hours of flight and 2 hours of audio data, recording of data is not changed as , black box data information is acquired in real - time aircraft sensors and related systems, must be retained before power - off is at least 25 hours of flight and 2 hours of audio data, recording of data is not changed as .
aircraft data, objective and comprehensive record - keeping, the box was following the crash to pinpoint the cause of the most reliable, most scientific, most effective means of aircraft data, objective and comprehensive record - keeping, the box was following the crash to pinpoint the cause of the most reliable, most scientific, most effective means of . accompanied by the development of aviation, aircraft black boxes in the daily safety maintenance, flight status monitoring,hidden danger of accident and fault localization is also playing an increasingly important role, and even can be said to act as the indispensable role of the flight of the first to take advantage of the black box is accompanied by the development of aviation, aircraft black boxes in the daily safety maintenance, flight status monitoring,hidden danger of accident and fault localization is also playing an increasingly important role, and even can be said to act as the indispensable role of the flight of the first to take advantage of the black box is .
. military aircraft in 1908, with the U.S. in its first military aircraft accident
, Along with the increase of flight accidents, there was an urgent need for research into the cause of the , Along with the increase of flight accidents, there was an urgent need for research into the cause of the . instrument during World War II, the flight recorders from the formal to military aircraft used postwar instrument during World War II, the flight recorders from the formal to military aircraft used postwar .
, , . began to use the civil aircraft of the early records on the way backward, and is equipped with a mechanical recording method, recording on the photographic paper in the recording in the invention of began to use the civil aircraft of the early records on the way backward, and is equipped with a mechanical recording method, recording on the photographic paper in the recording in the invention of .
, , . becomes convenient and reliable becomes convenient and reliable.
Species
common flight recorder of the engraved foil type, optical type oscilloscope, photography type and a tape type 4 common flight recorder of the engraved foil type, optical type oscilloscope, photography type and a tape type 4 .
Engraved Foil Type
As the recording medium of the metal foil strip by a constant speed, the scrolling device, engraved by needle scribing in the foil strip are to be recorded and record As the recording medium of the metal foil strip by a constant speed, the scrolling device, engraved by needle scribing in the foil strip are to be recorded and record . stylus deflection amplitude is proportional to the size of the recording parameter stylus deflection amplitude is proportional to the size of the recording parameter .
The Optical Type Oscilloscope
using the photographic prints or photographic film as the recording medium, which is driven by a first constant by the drive device through the exposure groove, by a galvanometer mirror of the reflected light beam is precisely in projection exposure, the recording medium for exposure will be recorded and record using the photographic prints or photographic film as the recording medium, which is driven by a first constant by the drive device through the exposure groove, by a galvanometer mirror of the reflected light beam is precisely in projection exposure, the recording medium for exposure will be recorded and record . beam upon deflection of the galvanometer is applied on a current proportional to the current, i.e. they are in contact with an amount proportional to the size of the
Photographic Type
record indicating that the test instrument is mounted on the dashboard, by a camera of the instrument indication record indicating that the test instrument is mounted on the dashboard, by a camera of the instrument indication . film after rinsing, to each picture on a screen, each meter reading film after rinsing, to each picture on a screen, each meter reading .
Tape Type
recorded on a magnetic tape by converting the quantity of the magnetic field changes, the playback parameter are recorded after the data reduction, for analysis of flight recorder recorded on a magnetic tape by converting the quantity of the magnetic field changes, the playback parameter are recorded after the data reduction, for analysis of flight recorder . tape - head multi - channels, such as 14 Road, 28 Road tape - head multi - channels, such as 14 Road, 28 Road .
recording format has a direct analog, pulse - width modulation, frequency modulation and pulse code modulation (digital) and recording format has a direct analog, pulse - width modulation, frequency modulation and pulse code modulation (digital) and . tape recorder for recording large capacity, high precision, easy - to - computer interface with digital automatic data processing tape recorder for recording large capacity, high precision, easy - to - computer interface with digital automatic data processing .
Use
Accident Analysis
People may be recorded before the crash of an aircraft altitude, speed, heading, vertical overload, pitch, roll, and the control surfaces of the deflection angle, lift, drag, and the engine power and the like information as well as the machine inner dialogue and pilots and ground communications, analyze reasons of People may be recorded before the crash of an aircraft altitude, speed, heading, vertical overload, pitch, roll, and the control surfaces of the deflection angle, lift, drag, and the engine power and the like information as well as the machine inner dialogue and pilots and ground communications, analyze reasons of . may also be recorded by the flight recorder information, processed and then transmitted to the flight simulators, which reproduce the crash elapsed, the image analysis of the cause of the accident and may also be recorded by the flight recorder information, processed and then transmitted to the flight simulators, which reproduce the crash elapsed, the image analysis of the cause of the accident and .
- - as in many countries stipulate that the aircraft must be installed for accident analysis for the flight recorders, commonly known as the "black box", but in fact it is often coated on the surface of the eye - catching color such as orange) to find - - as in many countries stipulate that the aircraft must be installed for accident analysis for the flight recorders, commonly known as the "black box", but in fact it is often coated on the surface of the eye - catching color such as orange) to find .
Condition - Based Maintenance (CBM)
Some states have taken the aircraft and engine maintenance systems, i.e., periodic maintenance is changed according to actual demands. The inspection and maintenance of flight recorder data can be recorded for reference important information flight recorder data can be recorded for reference important information .
Flight Test
Flight test aircraft is developed and the theory study of important t Flight test aircraft is developed and the theory study of important t . flight data in the trial of, a portion of the telemetry device against the back ground, most of the flight recorder, for further analysis, for example, a portion of each of the flight data in the trial of, a portion of the telemetry device against the back ground, most of the flight recorder, for further analysis, for example, a portion of each of the .
aircraft flutter behaviour can be strain gauges, accelerometers and a speed sensor are measured and recorded in the tape, and then performs the spectrum and power spectrum analysis, in order to decide on a certain part of the structure of the inertia, stiffness, and the aerodynamic factors whether to modify a certain aircraft flutter behaviour can be strain gauges, accelerometers and a speed sensor are measured and recorded in the tape, and then performs the spectrum and power spectrum analysis, in order to decide on a certain part of the structure of the inertia, stiffness, and the aerodynamic factors whether to modify a certain . as another example, ambient vibration data of the recording and analysis, not only on the fatigue life research is very useful,but may be an onboard instrumentation equipment design as another example, ambient vibration data of the recording and analysis, not only on the fatigue life research is very useful,but may be an onboard instrumentation equipment design .
Development Type
With black box flight safety of aircraft and urgent demands on the level of technology progress and rapid development, industries, there is no comparison of identity within the black box from the naissance to now development of generations of first - generation black box: born in the early 1950s, in the plane's flight - test design is an improvement on the basis of the recording equipment. Its working principle is through the metal foil strip by a needle to score to reflect the change curve of the data, the record only heading, altitude, airspeed, vertical overload and the flight time of five second - generation black box parameter : appeared in the late 1950s, its working principle is similar to that of the ordinary,But on the tape drive is additionally having shock resistance, such as fire on the ability of the protective housing, according to Federal Aviation Administration (FAA) issued the first one of the standard was TSO - C51, requirements for black box capable of withstanding 100 g (gravitational acceleration), duration 11 ms for shock, and 1100. degree. C., 30 minutes of fire
1966 update standard was TSO - C91a C51a, anti strong shock index increased to 1000 g, and increases the penetration resistance, static deflection, resistance to seawater immersion, the immersion liquid corrosion and the like require a second - generation black box 1966 update standard was TSO - C91a C51a, anti strong shock index increased to 1000 g, and increases the penetration resistance, static deflection, resistance to seawater immersion, the immersion liquid corrosion and the like require a second - generation black box . can generally be recorded dozens of parameters,and the change occurred in the cockpit audio recorder can generally be recorded dozens of parameters,and the change occurred in the cockpit audio recorder .
third - generation black box: appeared in the 1990s to third - generation black box: appeared in the 1990s to . As microelectronic technology advanced by leaps and bounds, their voices started to be used for a semiconductor memory recording data, as the aircraft when it crashed on the destruction to the understandings of the black box, black box crash proof ability standard is updated to the TSO - C124, resisting strong impact metrics to the shocking, 1100 DEG C and the burning time was increased to 60 minutes, wherein the outer layer and the immersion time increased from 36 hours to 30 days, increases resistance to 6000 meters in the deep sea pressure requirements As microelectronic technology advanced by leaps and bounds, their voices started to be used for a semiconductor memory recording data, as the aircraft when it crashed on the destruction to the understandings of the black box, black box crash proof ability standard is updated to the TSO - C124, resisting strong impact metrics to the shocking, 1100 DEG C and the burning time was increased to 60 minutes, wherein the outer layer and the immersion time increased from 36 hours to 30 days, increases resistance to 6000 meters in the deep sea pressure requirements .
in 1996,FAA TSO - C124a issued a standard, increasing the resistance to 260. degree. C., 10 - hour requirement of fire 3rd generation of the black boxes are usually in the hundreds, from the function has been used in flight accident investigation, gradually extending to day - to - day monitoring of pilots, aircraft maintenance and fault diagnosis a new generation of 3rd generation of the black boxes are usually in the hundreds, from the function has been used in flight accident investigation, gradually extending to day - to - day monitoring of pilots, aircraft maintenance and fault diagnosis a new generation of .
black box may record video information, recording of the control parameters in the thousands, and is capable of data transmission via satellite, regular black box of the critical data black box may record video information, recording of the control parameters in the thousands, and is capable of data transmission via satellite, regular black box of the critical data . but because of the need to take account of the bandwidth and signal blind spots and meteorological environment and the like, data real - time transfers cannot completely replace the traditional role of but because of the need to take account of the bandwidth and signal blind spots and meteorological environment and the like, data real - time transfers cannot completely replace the traditional role of .
black boxes, and - -Novel polishing and in the style of the black box is already present and can be in the plane crash is automatically separated from the company, as well as floating and radio, satellite positioning function black boxes, and - -Novel polishing and in the style of the black box is already present and can be in the plane crash is automatically separated from the company, as well as floating and radio, satellite positioning function . Along with the quick development of science and technology, the black box is constantly updated in Along with the quick development of science and technology, the black box is constantly updated in .
1960s advent of voyage data recorder (FDR), could onlybe recorded 5 parameters, the error is large at the beginning of the 70s 1960s advent of voyage data recorder (FDR), could onlybe recorded 5 parameters, the error is large at the beginning of the 70s . tape using digital recording, writes down more than 100 parameters, save the last 25 hours of flight data tape using digital recording, writes down more than 100 parameters, save the last 25 hours of flight data .
in the 1990s after the integrated circuit memory, like computer memory, recording 2 hours sounds of CVR and FDR 25 hours of flight,crash analysis greatly improves the accuracy of the in the 1990s after the integrated circuit memory, like computer memory, recording 2 hours sounds of CVR and FDR 25 hours of flight,crash analysis greatly improves the accuracy of the .
Information Record
the Wright brothers had first use of the L - 3 Communications Inc., of the instrument this black box of an airplane propeller rotation however, until after World War II, aviation recorder only for the wider use of however, until after World War II, aviation recorder only for the wider use of .
since then, in order to obtain more information about the work of the aircraft, the black box of the recording medium to the development of since then, in order to obtain more information about the work of the aircraft, the black box of the recording medium to the development of . most of the black box of an airplane using two recording media, a magnetic tape is, invented in the 1960s; the other is electrically stored crystal plate, invented in the 1990s most of the black box of an airplane using two recording media, a magnetic tape is, invented in the 1960s; the other is electrically stored crystal plate, invented in the 1990s .
tape work like the tape recorder tape work like the tape recorder . mylar tape traction electromagnet - type head,magnetic tape for recording data on mylar tape traction electromagnet - type head,magnetic tape for recording data on .
because airlines have begun to turn to electronic technology, manufacturers are no longer manufactured magnetic tape recorder manufacturers Honeywell spokesman because airlines have begun to turn to electronic technology, manufacturers are no longer manufactured magnetic tape recorder manufacturers Honeywell spokesman . black box, an electronic recorder of reliability is much higher than that of the tape recorder | electronic recorder using the stacked arrangement of the memory chip, so that they do not have any of the pieces of the device,This also results in a decrease in the daily maintenance work during the occurrence of the accident and all of a sudden interruption of the chances black box, an electronic recorder of reliability is much higher than that of the tape recorder | electronic recorder using the stacked arrangement of the memory chip, so that they do not have any of the pieces of the device,This also results in a decrease in the daily maintenance work during the occurrence of the accident and all of a sudden interruption of the chances .
CVR and FDR data collected are recorded in a crash survivable memory unit (CSMU) in the stack memory in accordance with CVR and FDR data collected are recorded in a crash survivable memory unit (CSMU) in the stack memory in accordance with . L - 3 Communications, Inc., recorder, CSMU
stacked memory chip in the form of a cylinder having a diameter of about 1.75 inches (4 cm),high 1 inch (2.54 cm) memory chip has sufficient storage space for recording a digital CVR providing 2 hours of audio information and FDR provided 25 hours of flight data memory chip has sufficient storage space for recording a digital CVR providing 2 hours of audio information and FDR provided 25 hours of flight data .
aircraft is mounted on the sensor data acquisition of aircraft is mounted on the sensor data acquisition of . sensors detected aircraft acceleration, airspeed, altitude, wing setting, outside temperature, cabin temperature and pressure, engine performance and the like sensors detected aircraft acceleration, airspeed, altitude, wing setting, outside temperature, cabin temperature and pressure, engine performance and the like .
tape recorder can track the approximately 100 parameters,while electronic recorder can record a larger aircraft on more than 700 parameter tape recorder can track the approximately 100 parameters,while electronic recorder can record a larger aircraft on more than 700 parameter . all these sensor data are sent to the front end of the aircraft flight data acquisition unit ( all these sensor data are sent to the front end of the aircraft flight data acquisition unit (.
) of this instrument is often placed in the cockpit under the electronic device in the cofferdam ) of this instrument is often placed in the cockpit under the electronic device in the cofferdam . flight data acquisition unit acquires the whole data recording process in the middle of a manager, that is, from the sensor information, and then to a black box Blackbox flight data acquisition unit acquires the whole data recording process in the middle of a manager, that is, from the sensor information, and then to a black box Blackbox .
generally by one or two engine acquires energy from the engine power drives a generator generally by one or two engine acquires energy from the engine power drives a generator . is a 28 volt DC power supply, the other one is a 115 volt, is a 28 volt DC power supply, the other one is a 115 volt,.
400 Hz AC L - 3 Communications Corporation's director of engineering, says these are the standard of the aircraft power supply configuration 400 Hz AC L - 3 Communications Corporation's director of engineering, says these are the standard of the aircraft power supply configuration .
CVR
cockpit voice recorder (CVR) was a radio call recorder, can be recorded on the call that the cockpit voice recorder (CVR) was a radio call recorder, can be recorded on the call that the . instrument on four tracks were recorded with the ground pilot command organization of the call, that is, between the co - pilot's conversation, the captain, the flight attendants on the passenger speech. threats, bombings, abnormal sound engine, cockpit and all the voices in the
black box is able to provide an aircraft accident investigator before each system operation situation black box is able to provide an aircraft accident investigator before each system operation situation . because the crash happened in a short period, sometimes at the same time all pilots and flight attendants were killed, the investigation of the cause of the accident would have great difficulty,Cockpit recorder language can help people according to the crew of various dialogue and analysis the cause of the accident, the accident in order to make correct conclusions because the crash happened in a short period, sometimes at the same time all pilots and flight attendants were killed, the investigation of the cause of the accident would have great difficulty,Cockpit recorder language can help people according to the crew of various dialogue and analysis the cause of the accident, the accident in order to make correct conclusions .
cockpit voice recorder primarily records the crew and ground personnel of the call, the conversation between the crew and cockpit, various of audio (including operating the aircraft engine sound) cockpit voice recorder primarily records the crew and ground personnel of the call, the conversation between the crew and cockpit, various of audio (including operating the aircraft engine sound) . and the like which are similar to those of an ordinary tape recorder, tape - forever running constantly in a vintage recording new, always having the last recorded half - hour of the various sound and the like which are similar to those of an ordinary tape recorder, tape - forever running constantly in a vintage recording new, always having the last recorded half - hour of the various sound .
flight go through eight phases (takeoff, initial climb, climb, cruise, descent, began to approach, final approach, landing),Each stage of the case, the very concept of "ear" flight go through eight phases (takeoff, initial climb, climb, cruise, descent, began to approach, final approach, landing),Each stage of the case, the very concept of "ear" .
FDR
A flight data recorder (FDR) of various major recording aircraft flight data, including flight attitude, flight path (trajectory), velocity, acceleration, latitude and longitude, heading, and acting on the external force, such as drag, lift, thrust, and the like, a total of about 200 kinds of data, may be retained for a period of 20 hours of flight parameter A flight data recorder (FDR) of various major recording aircraft flight data, including flight attitude, flight path (trajectory), velocity, acceleration, latitude and longitude, heading, and acting on the external force, such as drag, lift, thrust, and the like, a total of about 200 kinds of data, may be retained for a period of 20 hours of flight parameter . this time has elapsed, the data logger will automatically get rid of the stale, old data is overwritten by new data from the flight this time has elapsed, the data logger will automatically get rid of the stale, old data is overwritten by new data from the flight .
providing people with the plane crash and moments before the crash, the aircraft flight condition, an on - board equipment work condition etc. It of aircraft height, speed, heading,rate of climb, descent rate, acceleration, gas mileage, retractable landing gear, Greenwich time, the aircraft system status and engine operating parameters such as the flight parameter record system of the aircraft recorded It of aircraft height, speed, heading,rate of climb, descent rate, acceleration, gas mileage, retractable landing gear, Greenwich time, the aircraft system status and engine operating parameters such as the flight parameter record system of the aircraft recorded .
. operation data from the different regions of the sensor connected to flight data acquisition unit, and may be connected to one switching action when FDR operation data from the different regions of the sensor connected to flight data acquisition unit, and may be connected to one switching action when FDR .
, , . FDR will be recorded electronic recorders due to the fast data transmission,so that as compared with the tape recorder to record more parameters FDR will be recorded electronic recorders due to the fast data transmission,so that as compared with the tape recorder to record more parameters .
electronic FDR can record 25 hours of flight data recorded by FDR electronic FDR can record 25 hours of flight data recorded by FDR . each additional parameter "may provide accident investigators of more clues to the each additional parameter "may provide accident investigators of more clues to the .
in the United States, the Federal Aviation Administration (FAA) requirements for commercial airlines, according to the size of the aircraft, at least 11 - 29 record parameter in the United States, the Federal Aviation Administration (FAA) requirements for commercial airlines, according to the size of the aircraft, at least 11 - 29 record parameter . tape recorder picks up to 100 parameters, and the electronic appliance can be recorded more than 700 parameter tape recorder picks up to 100 parameters, and the electronic appliance can be recorded more than 700 parameter .
1997 and 17 July, the FAA published a federal standard,The standard for 2002 on 19 August after manufacture of the aircraft parameter to be recorded at least 88 1997 and 17 July, the FAA published a federal standard,The standard for 2002 on 19 August after manufacture of the aircraft parameter to be recorded at least 88 . in the installation position of the black box is typically mounted at the back, in the installation position of the black box is typically mounted at the back, .
because, by scientists for so many flight accident is analyzed by means of the aircraft tail portion are not easily damaged, so the black box mounted at the back, because, by scientists for so many flight accident is analyzed by means of the aircraft tail portion are not easily damaged, so the black box mounted at the back, .
Salvage Positioning
The current black box in the terrestrial positioning mainly depends on manual visualization, to locate the plane's wreckage, the black box looks bright, unique colors and retro - reflective markings in a search and The current black box in the terrestrial positioning mainly depends on manual visualization, to locate the plane's wreckage, the black box looks bright, unique colors and retro - reflective markings in a search and . black boxes underwater positioning mainly depends on the underwater locator beacon (ULB, Underwater Locator Beacon) black boxes underwater positioning mainly depends on the underwater locator beacon (ULB, Underwater Locator Beacon) .
it is a battery - powered underwater ultrasonic pulse generator, firmly attached to the outside once the black box recorders it is a battery - powered underwater ultrasonic pulse generator, firmly attached to the outside once the black box recorders . into water, the beacon on the water - sensitive switch to activate the beacon, the beacon passes through the metal housing of the frequency of 37 kHz ultrasonic signal is emitted to the surrounding waters, into water, the beacon on the water - sensitive switch to activate the beacon, the beacon passes through the metal housing of the frequency of 37 kHz ultrasonic signal is emitted to the surrounding waters,.
one pulse per second from a built - in battery can work continuously for at least 30 days, 30 days after the charge is gradually depleted, and the ultrasonic signal will be more muted, until the stop work one pulse per second from a built - in battery can work continuously for at least 30 days, 30 days after the charge is gradually depleted, and the ultrasonic signal will be more muted, until the stop work . 6096 meters beacons may be within the depth of the emitted ultrasound, but at a distance of 1800 to 3600 m beacon is in the range of the instrument can be detected, the state of the sea, ships, marine animals, oil pipelines and other factors caused by the surrounding noise can affect the beacon signal of the detected range 6096 meters beacons may be within the depth of the emitted ultrasound, but at a distance of 1800 to 3600 m beacon is in the range of the instrument can be detected, the state of the sea, ships, marine animals, oil pipelines and other factors caused by the surrounding noise can affect the beacon signal of the detected range .
underwater locator beacon is signalled,may be implemented by using sonar detectors positioned underwater locator beacon is signalled,may be implemented by using sonar detectors positioned . due to beacon signal detectable range with respect to the sea for extremely limited, usually to be positioned approximately in the range of the wreckage, and then by narrowing the range of that tow sonar positioning, and ultimately by using signal source can be positioned in the direction of the hydrophone, positioning the recorders' pings due to beacon signal detectable range with respect to the sea for extremely limited, usually to be positioned approximately in the range of the wreckage, and then by narrowing the range of that tow sonar positioning, and ultimately by using signal source can be positioned in the direction of the hydrophone, positioning the recorders' pings .
if under shallow seas, the divers salvaging the black box if if under shallow seas, the divers salvaging the black box if . sank to the ocean depths, and then exceed manual diving depth, the use of specialized search, salvage equipment, general practice to use a drop - by - wire (BBW) ship underwater robot, the operator on the ship through the integrated display of the console,control of the robot carrying scan sonar equipment of submarine, the orientation of the locator beacon, deep black box camera positioning, by the manipulator salvage the black box sank to the ocean depths, and then exceed manual diving depth, the use of specialized search, salvage equipment, general practice to use a drop - by - wire (BBW) ship underwater robot, the operator on the ship through the integrated display of the console,control of the robot carrying scan sonar equipment of submarine, the orientation of the locator beacon, deep black box camera positioning, by the manipulator salvage the black box .
in the United States, when the accident investigators found the black box, it is immediately sent to the NTSB's computer laboratory with in the United States, when the accident investigators found the black box, it is immediately sent to the NTSB's computer laboratory with . in order to avoid any damage to the recording medium, the transport process in such a device is subject to special protection in the event of an accident underwater in order to avoid any damage to the recording medium, the transport process in such a device is subject to special protection in the event of an accident underwater .
, the recorder is stored in the water to prevent drying , the recorder is stored in the water to prevent drying . "everything for the purpose of preserving the status of the recorder until it is properly handled," said, "it places the recorder in a bucket of water, which is typically cold,i will be found in the local environment, until being served can be sufficiently analyzed black box where "everything for the purpose of preserving the status of the recorder until it is properly handled," said, "it places the recorder in a bucket of water, which is typically cold,i will be found in the local environment, until being served can be sufficiently analyzed black box where .
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Search Equipment
U.S. Navy's website, the TPL - 25 towed sonar towed by the underwater part, cable and desk etc dragging its underwater section has a length of about 30 inches (76 cm), with a diameter of about 35 inches (89 centimeters), weighs 70 pounds (32 kilograms) dragging its underwater section has a length of about 30 inches (76 cm), with a diameter of about 35 inches (89 centimeters), weighs 70 pounds (32 kilograms) .
Just as its name implies, the towed section will be the ships towing at sea and slow speed is usually 1 to 5 and save $1 - per - second (0 m), or the instrument itself can "listen" to the acoustic signal the sonar Just as its name implies, the towed section will be the ships towing at sea and slow speed is usually 1 to 5 and save $1 - per - second (0 m), or the instrument itself can "listen" to the acoustic signal the sonar . "hearing" highly sensitive, the deepest can "hear"black boxes underwater at 20,000 ft (6096 m) when the locator signal "hearing" highly sensitive, the deepest can "hear"black boxes underwater at 20,000 ft (6096 m) when the locator signal .
"listening" to the black signal, the signal will appear in the console of the oscilloscope or the signals may be processed on a computer controlling the "listening" to the black signal, the signal will appear in the console of the oscilloscope or the signals may be processed on a computer controlling the . operator will determine the strongest signal of the position of the recording, again repeatedly after the measurement by "triangulation" to determine the position of the black box recorders typically operator will determine the strongest signal of the position of the recording, again repeatedly after the measurement by "triangulation" to determine the position of the black box recorders typically .
per second to 37 kHz and the frequency of the signal, while the waves can be detected from the 3. 5 kHz to 50 kHz in the frequency band in which the various signal in 2009, the US will use the Towed lent in France,to look for Flight 447 black boxes - in 2009, the US will use the Towed lent in France,to look for Flight 447 black boxes - .
of the us pacific fleet in March 2014 on October 23 and will detect the black box of the Towed signal destined for the drawdown of troops involved in the hunt for the missing Malaysia Airlines plane, the apparatus of the system so as to implement the TPL - 25, may be detected over 6000 meters underwater depth of source of the us pacific fleet in March 2014 on October 23 and will detect the black box of the Towed signal destined for the drawdown of troops involved in the hunt for the missing Malaysia Airlines plane, the apparatus of the system so as to implement the TPL - 25, may be detected over 6000 meters underwater depth of source .
Preservation Method
In most of the crash, can be preserved for the device is a cockpit voice recorder and flight data recorder of the crashed short of the record unit (CSMU) In most of the crash, can be preserved for the device is a cockpit voice recorder and flight data recorder of the crashed short of the record unit (CSMU) . usually, recorder chassis and inner devices of the other portion has been torn away from usually, recorder chassis and inner devices of the other portion has been torn away from .
CSMU is fastened to the recorder of the platform part of a huge cylinder CSMU is fastened to the recorder of the platform part of a huge cylinder . such a device can withstand very high pressure, a very large impact and tons of pressure such a device can withstand very high pressure, a very large impact and tons of pressure .
old tape recorder,CSMU is housed in a rectangular box in old tape recorder,CSMU is housed in a rectangular box in . electronic black box using three layers of the CSMU material stored in the memory of the digital information should be saved in the isolation sheet and electronic black box using three layers of the CSMU material stored in the memory of the digital information should be saved in the isolation sheet and .
. Let's discuss the problem, we need to look at from the inside to the outside of the protected memory of aluminum material shell, surrounds the memory card contains an aluminium thin aluminum material shell, surrounds the memory card contains an aluminium thin .
high temperature insulator, 1 inch (2.54 centimeters) of dry quartz material providing high temperature protection its protection memory prevents the post - accident fire its protection memory prevents the post - accident fire .
stainless steel housing, a high temperature insulator installed at 0. 25 inches (64 cm) thick stainless steel housing, usually made of titanium alloy with in order to ensure the quality and viability of the black box,A manufacturers CSMU conducted thorough tests in order to ensure the quality and viability of the black box,A manufacturers CSMU conducted thorough tests .
remember, in a plane crash, CSMU can only survive if accident investigators to obtain it, and thus it is possible to obtain the information they want and remember, in a plane crash, CSMU can only survive if accident investigators to obtain it, and thus it is possible to obtain the information they want and . CSMU To test, engineers will have data stored in the memory in the CSMU CSMU To test, engineers will have data stored in the memory in the CSMU .
L - 3 Communications Inc., a random model using the data stored in each memory in this model can be read by the reader to determine the impact of the crash, fire and under pressure is made as to whether the data is damaged in this model can be read by the reader to determine the impact of the crash, fire and under pressure is made as to whether the data is damaged .
Follow - Up Research And Development
Jettison The Black Box
On June 1, 2009, the Air France airliner flying from Rio de Janeiro to Paris flight crashed in the Atlantic, due to the black box and sank to the seabed 4,000 metres, over the course of two years before investigators retrieved the black box, which are very expensive to install On June 1, 2009, the Air France airliner flying from Rio de Janeiro to Paris flight crashed in the Atlantic, due to the black box and sank to the seabed 4,000 metres, over the course of two years before investigators retrieved the black box, which are very expensive to install . The Air France plane's black boxes with underwater locator beacon, but due to beacon range is only several kilometres it crashed, possibly with a separate black box, once the fishing time exceeds 30 days, the positioning signal may disappear, the black box locator The Air France plane's black boxes with underwater locator beacon, but due to beacon range is only several kilometres it crashed, possibly with a separate black box, once the fishing time exceeds 30 days, the positioning signal may disappear, the black box locator .
difficulties even if succeeded in positioning, deep sea fishing there is also a difficult, long and expensive, and didn't even need fishing etc. According to the statistics question ,1970 ~ 2009, large civil aircraft crashed in the high seas of 36 in connection with four case found the wreckage of the aircraft, nine found the black box, reflect the underwater locator beacon positioned in such a way that there is certain limitation in addition to the ,1970 ~ 2009, large civil aircraft crashed in the high seas of 36 in connection with four case found the wreckage of the aircraft, nine found the black box, reflect the underwater locator beacon positioned in such a way that there is certain limitation in addition to the .
black box capable of positioning signal is emitted after the accident, aviation regulations require passenger and above the aircraft must be equipped with at least one emergency locator transmitter (ELT),In its post - accident through radio and satellite positioning signals are transmitted in such a manner that the surface of the water but if black box capable of positioning signal is emitted after the accident, aviation regulations require passenger and above the aircraft must be equipped with at least one emergency locator transmitter (ELT),In its post - accident through radio and satellite positioning signals are transmitted in such a manner that the surface of the water but if . wrecked what was left of it is too late to open carry and ELT, or ELT and the wreckage sank with all underwater, they will not hold wrecked what was left of it is too late to open carry and ELT, or ELT and the wreckage sank with all underwater, they will not hold .
statistics, flight accident in ELT has been instrumental in only 29% statistics, flight accident in ELT has been instrumental in only 29% . from the obtained information, a plurality of flight MH370 of ELT equipment no from the obtained information, a plurality of flight MH370 of ELT equipment no .
In addition, although the conventional black box crash proof performance of the standard is improving constantly, however in some serious accidents, damaged black box of the case have taken place from time to time. According to the statistics,Land the plane that crashed in a black box with a survival rate of 82% According to the statistics,Land the plane that crashed in a black box with a survival rate of 82% .
In order to solve the water difficulty positioning the accident after salvaging the black box and black box accident after the survival rate of less than 100%, cast to type In order to solve the water difficulty positioning the accident after salvaging the black box and black box accident after the survival rate of less than 100%, cast to type . such black box Blackbox emerges through its crash sensor monitoring accidents when the aircraft touches the ground or sea and for the moment at which the abnormal change of characteristic parameters can be quickly controlled with rich and throw the separation principle with the car at the moment of impact the airbag release similar such black box Blackbox emerges through its crash sensor monitoring accidents when the aircraft touches the ground or sea and for the moment at which the abnormal change of characteristic parameters can be quickly controlled with rich and throw the separation principle with the car at the moment of impact the airbag release similar .
accident black box in an instant following, if it drops on the land, which can avoid the wreckage of the impact and damage (burning; if falling in the sea, can be avoided with the bottom of the sea,Its design also ensures that the predetermined attitude of the float in the sea after accident black box in an instant following, if it drops on the land, which can avoid the wreckage of the impact and damage (burning; if falling in the sea, can be avoided with the bottom of the sea,Its design also ensures that the predetermined attitude of the float in the sea after ., black box via radio and satellite positioning signal automatic positioning , black box via radio and satellite positioning signal automatic positioning .
shall throw the black box of the process is carried out first by the COSPAS - SARSAT 406 MHz frequency was determined to be the search range, and then by 121 MHz. The frequency of the radio locator for completion of the positioning satellite can achieve global positioning, radio positioning generally in the range of tens to hundreds of kilometres due to having the above characteristics, the casting through type black box not only facilitate the search and salvage after the accident, while the conventional black box of the backup data to improve the survival rate of due to having the above characteristics, the casting through type black box not only facilitate the search and salvage after the accident, while the conventional black box of the backup data to improve the survival rate of .
China's Development
China's aircraft black box technology though started late, but on the international civil aviation standards, product development have also gone through four generations of China's aircraft black box technology though started late, but on the international civil aviation standards, product development have also gone through four generations of . China already has national airliners crash protection performance verification laboratory in 1978, when China and the first audio or video tape recorders; 1990 is a development of the nation's first uses a semiconductor recording medium of the black box; in 1991 by China's first airborne airworthiness; and in 2000 was developed following the successful TSO - C124a standard black box and in 2012 the company has successfully developed anti - aircraft black box of crashed at high speed,A TSO - C91a C124b beyond the standard requirements of its new China already has national airliners crash protection performance verification laboratory in 1978, when China and the first audio or video tape recorders; 1990 is a development of the nation's first uses a semiconductor recording medium of the black box; in 1991 by China's first airborne airworthiness; and in 2000 was developed following the successful TSO - C124a standard black box and in 2012 the company has successfully developed anti - aircraft black box of crashed at high speed,A TSO - C91a C124b beyond the standard requirements of its new .
jettison black box type, and includes a floating, radio and satellite positioning function in Chinese type jettison black box type, and includes a floating, radio and satellite positioning function in Chinese type . shall throw the black boxes in the field of international development shall throw the black boxes in the field of international development .
according to the latest international standards have been developed in the relevant products, has crashed before throwing a playback function, the resistance to impact and fire, having a floating function, there are provided on the inside of the positioning radio beacon, the Beidou satellite locating beacons, can work under complex sea according to the latest international standards have been developed in the relevant products, has crashed before throwing a playback function, the resistance to impact and fire, having a floating function, there are provided on the inside of the positioning radio beacon, the Beidou satellite locating beacons, can work under complex sea . especially built for the Beidou satellite locating beacon that can be positioned immediately after the crash, the performance is superior to the general purpose of the international COSPAS - SARSAT system,1 hour and the latter with the average delay time of the positioning, it is also possible by means of a short message function directly to the ground command center sending alarm and orientation data for the first time accurate positioning and rescue salvage, improves the efficiency of accident rescue, and shorten the course of the accident investigation time especially built for the Beidou satellite locating beacon that can be positioned immediately after the crash, the performance is superior to the general purpose of the international COSPAS - SARSAT system,1 hour and the latter with the average delay time of the positioning, it is also possible by means of a short message function directly to the ground command center sending alarm and orientation data for the first time accurate positioning and rescue salvage, improves the efficiency of accident rescue, and shorten the course of the accident investigation time .
this system of Beidou short message functionalities may also be configured as a normal flight of the plane in the key information of the periodic report this system of Beidou short message functionalities may also be configured as a normal flight of the plane in the key information of the periodic report .
Standard Formulation
Throughout the decades' pings's development of its international standards and the production of the pre - update, always draw on experience and accident investigation focusing on the progress of Throughout the decades' pings's development of its international standards and the production of the pre - update, always draw on experience and accident investigation focusing on the progress of . 2009 Air France 2014 Malaysia Airlines accidents and incidents, has exposed the maritime aviation accident after the emergency positioning function, the conventional black box locator and the salvage of technical deficiencies, is long, costly problems such as how to meet 2009 Air France 2014 Malaysia Airlines accidents and incidents, has exposed the maritime aviation accident after the emergency positioning function, the conventional black box locator and the salvage of technical deficiencies, is long, costly problems such as how to meet .
black box similar to the accident rescue and investigation, the industry has become an important topic in the 2012 black box similar to the accident rescue and investigation, the industry has become an important topic in the 2012 . convened a meeting of the International Civil Aviation Organization (ICAO),a flight recorder from the Group of Experts recommended that in the long distance crossing sea plane operated on, and the installation of emergency positioning function shall throw the black box type convened a meeting of the International Civil Aviation Organization (ICAO),a flight recorder from the Group of Experts recommended that in the long distance crossing sea plane operated on, and the installation of emergency positioning function shall throw the black box type .
relevant airworthiness standards already enacted by a major international manufacturers have already started implementing this work relevant airworthiness standards already enacted by a major international manufacturers have already started implementing this work .
Requirements
In order to ensure the safe recovery of the flight recorder in the structural design on special changes, such as impact - resistant, refractory, corrosion, etc., accident data recorder and the tape used are more particularly stringent technical requirements and harsh environmental conditions require accident data recorder and the tape used are more particularly stringent technical requirements and harsh environmental conditions require .
recorder is subjected to crash impact, penetration, compression, ignition, and a liquid contaminant including seawater immersion (impregnation) after recording tape shall be able to recover recorder is subjected to crash impact, penetration, compression, ignition, and a liquid contaminant including seawater immersion (impregnation) after recording tape shall be able to recover . has a limited number of products of recorder environment test requirement: all the three directions can be subjected to the overload and 1000 g of 23 kN (2,300 kg) force of impact;fire 30 minutes temperature rise up to 1100 c while the interior of the tape does not burn; soaking in water for 36 hours inside the tape has not been made moist; has a limited number of products of recorder environment test requirement: all the three directions can be subjected to the overload and 1000 g of 23 kN (2,300 kg) force of impact;fire 30 minutes temperature rise up to 1100 c while the interior of the tape does not burn; soaking in water for 36 hours inside the tape has not been made moist; .
etc. Furthermore, the recorder falls into the sea shall be 30 days have automatically signals, so that the fishing people and find recorder is generally installed in the body or projectile and to avoid the crash, such as a vertical tail on recorder is generally installed in the body or projectile and to avoid the crash, such as a vertical tail on .
2 2.
Difficulty Of Recovery
black box positioning signals transmitted on land it can stand, can be reached from dozens of kilometers of range, but its signal on the surface of the sea or water will be influenced greatly because of the obstacles, the signal strength is extremely reduced, and in 2009 Air France plane crash search and rescue operation in the subsequent process, the black boxes underwater in kilometers, and is completely unable to pronounce the signal black box positioning signals transmitted on land it can stand, can be reached from dozens of kilometers of range, but its signal on the surface of the sea or water will be influenced greatly because of the obstacles, the signal strength is extremely reduced, and in 2009 Air France plane crash search and rescue operation in the subsequent process, the black boxes underwater in kilometers, and is completely unable to pronounce the signal . explains why the difficulty of searching the crash explains why the difficulty of searching the crash .
so high that if a fall in the sea, and the "black box" as soon as the contact surface, may be signalled, and starts the position function, do not have a high level of rescue and missing areas of the coast in too far, is likely to cause "black box" so high that if a fall in the sea, and the "black box" as soon as the contact surface, may be signalled, and starts the position function, do not have a high level of rescue and missing areas of the coast in too far, is likely to cause "black box". undetected signal 3 black box with strong fire - resistance, compression resistance, impact resistance, vibration resistance to seawater (or kerosene), anti - magnetic disturbance capability, but even in this case, if the explosion occurred, likely in the black box is damaged in the explosion undetected signal 3 black box with strong fire - resistance, compression resistance, impact resistance, vibration resistance to seawater (or kerosene), anti - magnetic disturbance capability, but even in this case, if the explosion occurred, likely in the black box is damaged in the explosion .
4 March 8 2014, the flight from Kuala Lumpur bound for Beijing, said the flight MH370 lost contact, the plane carrying 239 people, including 154 Chinese passengers 4 March 8 2014, the flight from Kuala Lumpur bound for Beijing, said the flight MH370 lost contact, the plane carrying 239 people, including 154 Chinese passengers . after the incident, by the multinational composition of rescue ships have been in the scene to search for, the morning of 9 March, Malaysia Airlines officials speculated,not found the black box could be the cause of the aircraft disintegrated serious after the incident, by the multinational composition of rescue ships have been in the scene to search for, the morning of 9 March, Malaysia Airlines officials speculated,not found the black box could be the cause of the aircraft disintegrated serious .
As of 10 March Zero, Still no result As of 10 March Zero, Still no result . 4 4.
Case
Missing Malaysia Airlines Jet
On March 24, 2014, confirmed the missing Malaysia Airlines plane that crashed, but the cause of the accident was still unknown On March 24, 2014, confirmed the missing Malaysia Airlines plane that crashed, but the cause of the accident was still unknown . Given signals can be transmitted by the flight recorder ("black box") battery life, It's only 12 days, finding the black boxes - - - - how to become more pressing after Given signals can be transmitted by the flight recorder ("black box") battery life, It's only 12 days, finding the black boxes - - - - how to become more pressing after .
media speculated that the airliner's black box is likely to fall into deep water and seawater cause the signal to be shielded media speculated that the airliner's black box is likely to fall into deep water and seawater cause the signal to be shielded . US is looking at one to search specifically for black box of high - tech equipment to search the waters, supporting countries in their search for the missing airliner US is looking at one to search specifically for black box of high - tech equipment to search the waters, supporting countries in their search for the missing airliner .
March 25, 2014 China's Ministry of Transport on the missing Malaysia Airlines plane in maritime search and rescue programme has made new deployment,emphasize the search work are still the first priority and at the same time continue the search and salvage the wreckage of the plane, finding the black boxes from March 25, 2014 China's Ministry of Transport on the missing Malaysia Airlines plane in maritime search and rescue programme has made new deployment,emphasize the search work are still the first priority and at the same time continue the search and salvage the wreckage of the plane, finding the black boxes from . current situation depends on the weather or the geography of the area search, temperature conditions, the search for black boxes is not a simple piece of work, while the black box usually can emit signals for 30 days, from Feb. 8), which has been missing for 18 days, leaving the search party. I didn't have a lot of time
Malaysia's Oct. 25, based on the latest results of the analysis, has narrowed for the Malaysia Airlines flight MH370 search range,Now all rescue efforts focused on the southern corridor south of one of approximately 9 million square nautical mile area 2014 Apr. 5, in the black box close to the life time of 30 days, China's Haixun 01 has wheels at latitude 25 degrees north and longitude 101 degrees near the waters of the southern Indian Ocean to search black box instrument by listening to the frequency of 37 kHz and the pulse signal once per second, the missing jet, might be a correlation, it is fully confirms
2014 the morning of 6 April, equipped with black box searching devices of the US, Australia "Ocean Shield" warships, twice in the search area of the far north of the Great Wall to the pulse signal,the first back - to - 2 hours 20 minutes, the second lasted 13 minutes 2014 the morning of 6 April, equipped with black box searching devices of the US, Australia "Ocean Shield" warships, twice in the search area of the far north of the Great Wall to the pulse signal,the first back - to - 2 hours 20 minutes, the second lasted 13 minutes . April 8, 2014, a total of 14 aircraft and 14 ships in the Australian side to determine the near 77600 sqkm of a corridor search April 8, 2014, a total of 14 aircraft and 14 ships in the Australian side to determine the near 77600 sqkm of a corridor search .
this region is considered part of the aircraft is most likely due to falling of the position of the this region is considered part of the aircraft is most likely due to falling of the position of the . in this area of north and south end, the Chinese and Australian ships reported search respectively received pulse signal in this area of north and south end, the Chinese and Australian ships reported search respectively received pulse signal .
April 2014, with the possible exception of Australia held a briefing MH370 search phase case April 2014, with the possible exception of Australia held a briefing MH370 search phase case . Australia searching for the missing Malaysia Airlines flight flights, general coordinator of the Joint Agency Coordination Center (JACC) based in Houston, announced,Ocean Shield is found to be twice the signal, the first back - to - 5 minutes 32 seconds, the second for a period of 7 minutes, by far, the Ocean Shield found a total of four signals, signals consistent with black box feature Australia searching for the missing Malaysia Airlines flight flights, general coordinator of the Joint Agency Coordination Center (JACC) based in Houston, announced,Ocean Shield is found to be twice the signal, the first back - to - 5 minutes 32 seconds, the second for a period of 7 minutes, by far, the Ocean Shield found a total of four signals, signals consistent with black box feature .
Ocean Shield detected the signals of the time, respectively, by Saturday afternoon local time 4: 45 am, 9: 20 points Tuesday afternoon for the 4: 20, 10: 17 minutes Ocean Shield detected the signals of the time, respectively, by Saturday afternoon local time 4: 45 am, 9: 20 points Tuesday afternoon for the 4: 20, 10: 17 minutes . late found that most of the signal is weak relatively late found that most of the signal is weak relatively .
On April 11, 2014 at noon, taking place in China, the visit of Australian Prime Minister Tony Abbott told the media he believed to have been the capture of the sets of the pulse signal,Malaysia Airlines flight MH370 is by the black boxes emit On April 11, 2014 at noon, taking place in China, the visit of Australian Prime Minister Tony Abbott told the media he believed to have been the capture of the sets of the pulse signal,Malaysia Airlines flight MH370 is by the black boxes emit . Abbott said that many of the search range and the signal source is still "several kilometers" distance, due to the black box, with a power supply may be close to depletion, a race against time to ongoing Abbott said that many of the search range and the signal source is still "several kilometers" distance, due to the black box, with a power supply may be close to depletion, a race against time to ongoing .
This is the case of Australia, the first official announcement of the capture of the previous pulse signals associated with MH370 This is the case of Australia, the first official announcement of the capture of the previous pulse signals associated with MH370 . earlier in the day, is responsible for search and command work of the Joint Agency Coordination Center (JACC) is responsible for any Houston said the search was still not made the breakthrough earlier in the day, is responsible for search and command work of the Joint Agency Coordination Center (JACC) is responsible for any Houston said the search was still not made the breakthrough .
