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The VDR (Voyage Data Recorder), is the maritime version of the black box utilized by airlines. The system is typically two-part, consisting of the data-collecting unit, which is connected to a protective capsule mounted on deck designed to withstand fire, deep sea pressure and shock, as well as penetration. It is used to capture incidents of navigation, but it can also provide valuable information to assess damage during heavy weather and monitoring performance as well as crew training.
Up-grading
Many ships equipped with VDR/SVDR satisfy the minimum regulatory requirements. However, members are encouraged use the equipment to document near missed events, conduct investigations into incidents and to conduct preventative maintenance. In addition, there are programs that can dramatically extend the period of time that VDR data is available from the current 12 hour minimum and a decision should be made about whether or not to upgrade to this.
The system is built around an industrial grade computer that can perform a number of functions including processing and encoding data received from the sensors. It then stores the data in a capsule designed to withstand an accident and provide evidence of what took place on the ship. The main components of the VDR system comprise a data collection unit, which is situated on the bridge, a separate power source along with an interface unit as well as backup batteries. The unit collects all information from integrated sources such as microphones for recording bridge audio, and then sends it to a Concentrator which is where a string of NMEA 0183 sentence is interpreted and then coded to be sent to the final recorded media.