VDR is the equivalent of a black box on an airplane. It documents the events of a maritime incident which includes the time and date of the accident, the location of the ship at the moment of the incident, its speed, course and so on. The information recorded is a valuable resource in identifying potential safety hazards and enhancing operational procedures.
In accordance with IMO regulations, the standard VDR is required to store a variety of information. These include the date and time that is referred to Coordinated Universal Time (UTC), vessel position (latitude longitude, latitude, coordinate reference), speed and heading and bridge audio (acquisition of voice messages recorded by one or more microphones placed on the bridge to record conversations and sound alarms) and Very High Frequency radio communications (VHF) and radar information (a faithful replica of the display that was in view at the time of recording), rudder order and response as well as engine response and order, watertight doors and their status, as well as the accelerations and hull stresses.
The system is composed of a concentrator, which encodes and processes data streams, sensors that input data to the concentrator and the final recording medium (FRM) which can withstand incidents and allow the recovery of voyage data. The FRM could be a fixed unit positioned on the vessel, or a retrievable floating device that is connected to the EPIRB to allow for the identification of the vessel quickly in the event of a catastrophe.
The most efficient way to ensure the integrity of an vdr system would be to make its use an integral component of bridge drills and training sessions for crews. The saved data can also be used to identify areas where training is needed as well as to improve bridge procedures and operational safety.
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