Flight recorder
Flight recorders (colloquially referred to as black boxes ) are recording devices carried on board larger aircraft ( aircraft and helicopters ), which store relevant flight data and aircraft parameters as well as acoustic information in a chronologically assigned manner during a flight. After an aircraft accident , they use the stored data to provide an additional opportunity to understand the course of the accident based on the behavior of the aircraft and its crew .
There are two types of black boxes: the flight data recorder (English: flight data recorder , shortly FDR) and the cockpit voice recorder ( cockpit voice recorder , just CVR). Both devices can also be combined in one Cockpit Voice and Data Recorder (CVDR).
Their construction is designed to ensure that the data is stored even after the high accelerations ( g-forces on impact) and temperatures that often occur . The housing of the CSMU (Crash-Survivable Memory Unit) with the storage unit (s), which is particularly resistant to deformation, must withstand a very high hydrostatic pressure ( water pressure in mWS ) for a long time , especially after accidents over deep sea areas .
Each recorder has an underwater direction finder transmitter for quick localization of devices that may have sunk into the water . In the worst case, however, this can be separated from the storage unit in the event of an accident, which makes it much more difficult or even impossible to find it.
technology
Today, the devices are usually installed in the middle or in the rear of the machine, which experience has shown is the least likely to be destroyed in an accident. Today's models are about the size of a shoebox, painted in a striking bright orange (similar to RAL 2005 ) and with equally striking inscriptions "FLIGHT RECORDER DO NOT OPEN" on one side in English and on the other in French "ENREGISTREUR DE VOL NE PAS OUVRIR "provided. The recording or storage unit (CSMU) must withstand heat effects of 1100 ° C for at least 60 minutes and be waterproof to a water depth of at least 6000 meters. Static permanent forces of 23 kN must be permitted from the outside. The device specifications are set out in the standardization guidelines for electronics in aviation of the European Organization for Civil Aviation Equipment in the document EUROCAE ED-112 ( Minimum Operational Performance Specification for Crash Protected Airborne Recorder Systems ). EUROCAE is the European equivalent of the US RTCA , which both work closely together.
Flight data recorder
The flight data recorder (FDR) or digital flight data recorder (DFDR) records a few to over a hundred flight parameters, depending on the technology. The most important of these are altitude (see also: Barometric altitude measurement in aviation ), airspeed relative to the air ("Airspeed") and ground speed ("Groundspeed"), positions of the rudders and lift aids ( slats / flaps / " flaps ”) as well as course and the roll-pitch-yaw angle . In addition, there may be data from the autopilot and flight management system (FMS) as well as values such as speed, oil and exhaust gas temperature ( EGT ) from the engine (s) ( piston engine , turboprop , jet turbine ).
Different storage media are used for this. In the early FDR, this was a metal foil made from Inconel , a heat-resistant nickel -based alloy . The Inconel foils had to be changed regularly because they could only be written on once. Such an FDR drew z. B. on these four parameters: barometric altitude , airspeed relative to the air (airspeed), compass - heading and rate of climb or descent (see also: Variometer ). The recording time of the 200 foot (61 meter) long imaging plate was 400 hours. Later the recording came on magnetic tape , which could register more parameters, whereby the oldest data records were overwritten on the endless loop.
The SSFDR ( solid state flight data recorder), which has been used since the 1990s, contains flash memories (more precisely: flash EEPROMs ) in which the oldest data records are overwritten. The memory chips, similar to a solid-state drive, are protected from environmental influences and housed in a particularly stable housing. The individual parameters are listed in the EUROCAE document ED 112. For example, the flight data recorder must withstand impacts of 3400 g for at least 6.5 milliseconds (full braking from 796 km / h over a distance of 72 cm), at temperatures of 1100 ° C there must be no loss of data and flames within the first 60 minutes and the housing must withstand heat of up to 260 ° C for 10 hours. The data must not be lost even in a water depth of 6000 meters.
The first aircraft accident in which an FDR played a role in determining the cause was the plane collision in New York City on December 16, 1960.
Flight profile recorder
Flight profile recorders (FPR) are recording devices that are known in the military field and can store detailed information about flights.
Voice recorder
The voice recorder ( English Cockpit Voice Recorder , CVR, German driver's cab sound recorder ) continuously records the last 30 to 120 minutes in an endless loop. This must begin automatically before the aircraft starts moving under its own power and continues uninterrupted until the pilots leave the aircraft. The acoustic signals are recorded chronologically on a magnetic tape or a semiconductor memory, depending on the version .
Cockpit voice recorders usually save all important acoustic events on board: The entire radio communication of the cockpit crew - in emergencies also via the microphones in the pilots' oxygen masks , conversations via the on-board intercom (s), announcements in the passenger area via the Cabin loudspeaker system as well as conversations in the cockpit via the cockpit microphone (s). The latter can also detect the actuation of levers or switches as well as acoustic signals from the flight management system and the navigation devices. These include B. during the approach, the message from the instrument landing system (ILS) when overflighting the leading or main entry mark ( outer marker / middle marker ).
The voice recorder often plays a crucial role when it comes to possible mistakes made by the crew (“pilot errors”) as the cause of an aircraft accident. You can also find out whether the alarm functions were active; Investigating the frequency spectrum of the background noise using a spectrum analyzer can provide additional information on interference in the engines.
Underwater location
Each flight recorder (CVR and FDR) is equipped with its own underwater locator beacon ( ULB for short , similar to an emergency beacon ). This transmitter (English pinger ) switches on when it comes into contact with water ( fresh or sea water ) and then periodically emits an ultrasonic signal with a frequency of 37.5 kHz. The 10 millisecond “ping” is sent once per second. This means that the signal can be differentiated from the otherwise usual frequency spectrum in the sea - i.e. the general noise under water caused by animals, ships or wave movements.
The sound pressure level at the transmitter is 160 decibels . As a result, the signal can typically be registered within a radius of 2000 meters at a specified maximum depth of 14000 feet (4370 meters) when it is emitted freely . The signal search is carried out with a special receiver in a towed pinger locator about 2000 m above the sea floor . Each ULB unit has its own lithium battery with a minimum shelf life of 6 years. Their capacity is large enough to ensure transmission operation for at least 30 days after activation. Newer ULBs have a guaranteed transmission time of 90 days.
Telemetry
The cause of the crash of Air France flight 447 in June 2009 could not be finally clarified for a long time, as flight data recorders and voice recorders were not found until the beginning of May 2011. Even before the flight recorder was found, Airbus began developing a flight recorder based on telemetry . The data is transmitted from the aircraft to a ground station by radio via satellite . The Airbus A220 are said to be the first aircraft to be equipped with this technology.
evaluation
Well-known research institutes that can evaluate flight recorders are:
- the Federal Bureau of Aircraft Accident Investigation (BFU) in Braunschweig
- the National Transportation Safety Board (NTSB) in the United States
- the Bureau d'Enquêtes et d'Analyses pour la sécurité de l'aviation civile (BEA) in France
- the Air Accidents Investigation Branch (AAIB) in the UK.
Demarcation
- ACARS delivers live data from large aircraft to ground stations via radio or satellites , but these messages must i. d. Usually sent manually by the crew and they contain very little data. With the AF 447 , the ACARS data could already be evaluated while the flight recorder was still being searched for.
- Engine Condition Monitoring (ECM) sends engine data to the manufacturers at regular intervals. On flight MH 370 , the ECM data gave the first indications that the aircraft involved in the accident must have flown longer than initially assumed.
- MODE-S transponders provide the aircraft's license plate number and altitude, but only if this data is requested from a ground station.
- ADS-B provides, among other things, the GPS position, altitude and the aircraft registration number, but only extends about 370 km.
Manufacturer
A leading manufacturer of flight recorders and voice recorders is L3 Aviation Products in Sarasota (Florida), of the division ( Division ) L3 Commercial Aviation of the US company L3 Technologies belongs. The company supplies equipment for the Airbus A350 , among other things .
Other providers are Hamilton Sundstrand (part of UTC Aerospace Systems since 2012 ), which manufacture flight data recorders for Boeing and McDonnell Douglas (part of the Boeing Company since 1997 ), Honeywell Aerospace ( Allied Signal until 1999 ) and Universal Avionics . Flight recorders cost between $ 10,000 and $ 15,000 .
history
The flight recorder was invented by the Australian aeronautical engineer David Warren of the Aeronautical Research Laboratories of Australia. As an investigator, he was involved in the investigation of an initially completely puzzling series of crashes involving the then ultra-modern De Havilland "Comet" jet planes in 1953 and 1954, in which there were neither survivors nor eyewitnesses who could be questioned about the cause. Warren, who had recently seen the then new, compact minifon - miniature wire-sound device at a trade fair , came up with the idea of developing a device that could record conversations in the cockpit and important instrument data on tape and save them after an accident to give the accident investigators important information. In 1954, Warren wrote a text with the title “A Device for Assisting Investigation into Aircraft Accidents” (Eng. A device for supporting aircraft accident investigations ). In 1957, Warren completed a prototype that was tested in flight. However, the Australian aviation authorities initially showed no great interest. It was not until 1960 that a Fokker Friendship crash in Queensland , which had never been resolved and in which all 29 occupants were killed, led to a lawsuit in which the judge ordered all Australian airlines to equip all aircraft with a voice recorder from 1963 onwards. In 1967, Australia became the first country in the world to require voice recorders and flight recorders on airplanes. The Hawker Siddeley Trident was from 1964 the first aircraft type that was equipped with a flight recorder as standard.
The first flight data recorders only recorded the barometric altitude and the airspeed, measured by means of a pitot tube, relative to the air.
Today's minimum equipment for the transport of people and things in commercial air traffic is regulated in JAR -OPS 1 and OPS 3.
criticism
In connection with aircraft accidents in the 2010s, such as the disappearance of MH370 in 2014 or the crash of Germanwings flight 9525 in 2015, criticism was expressed of the lack of further development of the flight recorders. The possibilities of today's technology were by no means exhausted, which was occasionally attributed to "convenience, stinginess and excessive bureaucracy".
Others
Since July 2002 certain ships have also had to be equipped with a similar device. It's called Voyage Data Recorder . The Federal Maritime and Hydrographic Agency writes on its website:
“Technically, these voyage data recorders are far superior to the flight data recorders, as they store a significantly larger variety of data. In addition to the usual voice recording, all important navigation and machine data as well as the display of the radar image, which is recorded four times per minute, are saved without loss in the VDR. [...] the "black box" [will] play a particularly important role as a reliable data source in the reconstruction of marine casualties. It will help to avoid the repetition of mistakes and to increase overall safety on ships. "
Pictures of black boxes
Cockpit voice recorder of EgyptAir flight 990 after recovery from the sea
Open flight data recorder, behind the cockpit voice recorder (CVR)
Flight recorder (FDR)
Diving robot with found flight recorder
Honeywell flight recorder
Web links
- How Black Boxes Work
- David Warren - Inventor of the Black Box Flight Recorder (en.)
- Cockpit Voice Recorder Database (en.)
- Flight data recorder and voice recorder of the TU-154M (11 + 02) in the Military History Museum of the Bundeswehr - Berlin-Gatow airfield (entry on Museum-digital.de)
See also
Individual evidence
- ↑ http://clacsec.lima.icao.int/Reuniones/2014/Sem-CAAS/Presentaciones/Ingles/Session%209.pdf
- ↑ History of Flight Recorders ( Memento from March 28, 2014 in the Internet Archive ) accessed on March 30, 2015 (English)
- ↑ The secret sauce of airplanes black box video on gizmodo.com, accessed April 2, 2015 (video in English)
- ↑ Endless Loop 1/4 Inch Magnetic Tape Assembly Image of a recovered magnetic tape unit on tsb.gc.ca, accessed on March 30, 2015
- ↑ see: Flight Data Recorder Factual Report Investigation of a Fairchild F 1000 FDR on atsb.gov.au, accessed on March 30, 2015 (pdf)
- ↑ FlugRevue August 2017, page 69, Aerospace A to Z, episode 28
- ↑ investigation report EX002-0 / 99th (PDF; 2.45MB) Federal Aircraft Accident Investigation Bureau , September 1999, p. 3 , accessed on July 18, 2016 .
- ↑ FA2100 Series Cockpit Voice and Data Recorders. L3 Commercial Aviation, accessed March 27, 2019 .
- ↑ Plane crash - The Black Box , Süddeutsche.de, May 17, 2010
- ↑ Flight recorder of missing Boeing: beeping from 4500 meters depth , mirror online on April 7, 2014 (accessed on March 31, 2015)
- ↑ DK120 / 90 - Recorder Beacon on dukaneseacom.com , accessed on March 26, 2019
- ↑ CSeries aims to be first with live 'black box' telemetry from September 2, 2010
- ↑ Spiegel-Online report on ECM data
- ↑ FA2100 Series on L3 Commercial Aviation / Avionics / Products
- ↑ A350 on the way to design freeze - In: Airbus Letter , November 2008 ( Memento from June 17, 2009 in the Internet Archive )
- ↑ hamiltonsundstrand.com ( Memento from May 16, 2008 in the Internet Archive )
- ↑ aerospace.honeywell.com ( Memento of the original from April 2, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ uasc.com
- ↑ http://electronics.howstuffworks.com/gadgets/other-gadgets/black-box.htm
- ^ Remarks of Tony Tyler at the IATA OPS Conference, Kuala Lumpur on iata.org April 1, 2014, accessed April 15, 2015
- ↑ The "black box" principle is broken. on Rheinische Post from April 1, 2015, accessed on April 15, 2015
- ↑ Site last changed on September 21, 2007 ( Memento of the original from August 19, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (accessed on July 1, 2013)
