VDR (Voyage Data Recorder) is the maritime version of the black box that airlines use. The system is typically two-parts, consisting a data-collection unit as well as a deck-mounted protection pod designed to withstand shock, fire, deep-sea pressurized, and penetration. It is used primarily to record navigation incidents but it can also provide valuable information for analysis of heavy weather damage and performance monitoring as well as training for crew members.

Up-grading

Many ships fitted with VDR/SVDR devices meet the minimum regulatory requirements, but Members are encouraged to think about using the equipment for incident investigation, preventive maintenance and bridge team training as well as for recording near misses. There are also packages which can extend the duration during which VDR data is available beyond the current minimum of 12 hours. It is important to make a decision taken as to whether or not to upgrade the equipment.

The system is built around an industrial computer that performs a number of functions including processing and encoding the data gathered from sensors. The data is stored in a capsule that is designed to stand up to an accident and provide evidence of what transpired on the vessel. The major components of the VDR system comprise a data collection unit that is located on the bridge, a separate power source and an interface unit, as well as backup batteries. The unit collects data from all integrated sources including microphones, which record bridge audio, and sends it to the Concentrator where a sequence of NMEA 0183 sentences is interpreted and encoded for transmission to the final recording medium.

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