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VDR (Voyage Data Recorder) is the maritime version of the black box that airlines use. The system is typically two-parts comprised of a data-collection device and a deck-mounted protective pod that is designed to withstand shock as well as fire, deep-sea pressing and penetration. It is used to record the events of navigation, but can also provide valuable information for analysis of damage caused by heavy weather, performance monitoring and crew training.
Up-grading
Many ships equipped with VDR/SVDR satisfy the minimum requirements of regulatory compliance. However, Members are encouraged to use the equipment to document near misses, conduct investigation into incidents as well as for preventative maintenance. There are also programs which can extend the period for which VDR data will be accessible beyond the minimum of 12 hours. It is important to make a decision taken on whether to upgrade.
The system is built on an industrial-grade computer that can perform various functions, including processing and encoding data received from sensors. The capsule is designed to withstand any disaster and keep the data. The key components of the VDR system are a data collection unit, which is situated on the bridge, a separate power source as well as an interface unit and backup batteries. The unit collects all information from integrated sources such as microphones to record bridge audio and transmits it to a Concentrator where a sequence of NMEA 0183 sentence is interpreted and then coded to be sent to the final recording media.