Black Box

When you hear the term ‘Black Box’, what’s the first thing that comes to mind?  Most would say an Airplane’s Flight Recorder.  Then wonder, what does this have to do with a blog posted by a data recovery service provider Well, it has everything to do with our business.  In fact, many would consider this the capstone of the data recovery business. The very moment when years spent working in the field culminates in a job that’s importance rivals all work done before it.  The greatest challenge a data recovery provider might ever encounter would be related to the Black Box, also known as an Airplanes Flight Recorder. But, this is not a story about an emergency call in the night or a tragic story of some horrific accident. It is about how an orange metal box, capable of withstanding the most extreme type of damage from fire, pressure or impact, became an object of interest for a data recovery service provider.  This interesting object called the Black Box.

 

The Black Box

 

By definition, a Black Box is a device, system or object which can be viewed in terms of its inputs, outputs or transfer characteristics, without any knowledge of its internal workings. By this definition, one might conclude that almost anything could be referred to as a Black Box: a transistor, software, the human brain, even life itself. The opposite of a Black Box is a system in which the inner components or logic are available for inspection and is most commonly referred to as a White Box.  Before we go any further, let’s discuss a few of the main functions in the system.  All type of aircraft, regardless of the condition of it’s flight can be viewed in terms of its input parameters and output parameters. The flight data recorder (FDR) is an independent device that preserves the recent history of the flight through the recording of dozens of parameters collected several times per second. The cockpit voice recorder (CVR) preserves the recent history of the sounds in the cockpit including the conversation of the pilots. The two recorders give a testimony, narrating the flight history with accuracy and impartiality, to assist in an investigation should that need ever arise.

black-box

Modern Flight Data Recorders (FDR) store data on solid state memory in much the same way as a Solid State Drive or SSD. SSD usually refers to a set of a Flash NAND memory chips accompanied with its controller. Since FDR are typically specified to withstand an impact of 3400 g and temperatures of over 1,000 °C (1,830 °F) there are no better data storage devices in use today than ones based on solid state technology. Like SSD controllers, the FDR features technologies such as compression, de-duplication and high-level encryption protocols. They provide greater data protection than the leading enterprise hard disk drives (excluding magnetic material, which has no chance of withstanding the immense heat that occurs when an airplane crashes). These complex and highly proprietary features can create some of the greatest challenges faced in data recovery. One such challenge is the chip-off flash NAND data recovery procedure.

Although tedious and time consuming data recovery from an FDR is a crucial task. It involves precision, the ability to work with raw data and the patience of a saint,  which then allows crash investigators and airplane manufacturers to better understand the specfics of the event.  By looking at the diagram above, you will notice that the memory module is well proteced inside of the FDR case. Once the Printed Circuit Board (PCB) is separated from the actual case the data recovery process can begin. In most cases the data related to the translation layer which is used for the flash memory is available from the manufacturer. Only in very rare cases would this data be withheld from the data recovery lab.  In those rare cases, processes such as reverse engineering would be applied.

In many cases an SSD data recovery will involve using what is known as a techno mode. Although there are other cases where it is necessary to apply a differenct method known as the chip-off technology. In this case the data recovery technician has to de-solder all memory chips off the board and read them separately into a file known as a “Dump”. From the Dump data will be extracted in a time consuming process involving specialized software tools.  This process requires a high level of experience and the ability to work with raw data.  In the data recovery world there is no greater challenge, making the process of recovering data from a Flight Data Recorder the absolute pinnacle of endeavors faced in our business.

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