The VDR (Voyage Data Recorder), is the maritime equivalent to the black box that is used by airlines. The system is usually two-part, comprising an information-collecting unit that is connected to a capsule that is deck-mounted designed to withstand fire, deep-sea pressure and shock, as well as penetration. It is used primarily to record incidents during navigation, but also provides useful data for heavy weather damage analysis and performance monitoring as well as for crew training.
Up-grading
Many ships fitted with VDR/SVDR technology meet the bare minimum regulatory requirements however, Members are urged to consider using the equipment for incident investigation as well as preventive maintenance and bridge team training as well as for recording near misses. There are also software options that could significantly extend the amount of time for which VDR data is accessible from the current minimum of 12 hours and a decision needs to be made about whether or not to upgrade to this.
The system is constructed around an industrial computer that performs a number of functions including processing and encoding information gathered by the sensors. It then stores the data in a capsule that is designed to survive an accident and provide proof of what occurred onboard the ship. The key components of the VDR system comprise a data collection unit that is located on the bridge, a dedicated power source as well as an interface unit and backup batteries. The unit gathers data from all integrated sources such as microphones that record bridge audio, and then sends it to the Concentrator, where the resulting NMEA 0183 sentences are interpreted and encoded to be transmitted to the final recording medium.
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