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 protective capsule mounted on deck designed to withstand fire, deep-sea pressure shock, and penetration. It is used to record the events of navigation, but can also provide valuable information to analyze damage from heavy weather and monitoring performance as well as crew training.

Up-grading

Many ships equipped with VDR/SVDR meet the minimum requirements of regulatory compliance. However, members are encouraged use the equipment to record near misses, conduct investigation into incidents as well as for preventive maintenance. Additionally, there are packages available that can significantly extend the duration for which VDR data is available beyond the current 12 hour minimum and a decision needs to be made on whether or not to upgrade to this.

The system is built on an industrial-grade processor that performs a number functions, including processing and encoding information received from sensors. It then stores the data in a capsule that is designed to stand up to an accident and provide evidence of what transpired on the ship. The primary components of the VDR system include a collection unit that is located on the bridge, a separate power source, an interface unit and batteries for backup. The unit gathers data from all sources integrated including microphones for recording bridge audio and transmits it to the Concentrator where a sequence of NMEA 0183 sentences is interpreted and encoded to be transmitted to the final recording medium.

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