VDR (Voyage Data Recorder) is the maritime equivalent of the black box airlines use. It is typically made up of two parts that include a data collection unit and a deck-mounted safety pod that is designed to resist shock, fire, deep-sea pressurized, and penetration. It is used to document 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 with VDR/SVDR meet the minimum requirements of regulatory compliance. However, members are encouraged to use the equipment to document near misses, conduct incident investigations as well as for preventative maintenance. There are also programs that can dramatically extend the duration for which VDR data is available beyond the current minimum of 12 hours and a decision must be taken on whether or not to upgrade to this.
The system is constructed around an industrial computer that carries out a number of functions including processing and encoding information gathered by the sensors. The capsule is designed to withstand any disaster and keep the data. The VDR system consists of an data collection device situated on the bridge as also a dedicated power supply, an interface unit, and backup batteries. The unit collects all data from integrated sources including microphones to record bridge audio and sends it to a Concentrator where a sequence of NMEA 0183 sentences is interpreted and encoded for transmission to the final recording media.
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