VDR is a ship’s equivalent to the black box in an aeroplane. It documents all the details of a maritime accident, including the date, time as well as the location, speed and the course of the vessel. The data gathered can be used to identify potential safety hazards and improve operations procedures.
According to IMO regulations, the standard VDR is required to store an array of information. This includes: date and time referenced to Coordinated Universal Time (UTC), vessel position (latitude longitude, latitude, coordinate reference) speed and heading, bridge audio (acquisition of voice messages recorded by one or more microphones installed on the bridge for recording conversations and audible alarms) and Very High Frequency radio communications (VHF) and radar data (a faithful representation of the display that was visible at the time of the recording) the rudder’s order and response as well as engine response and order watertight doors as well as their status, as well as the hull’s accelerations and stresses.
The system is composed of a concentrator which processes and encodes data streams, sensors that send data to the concentrator and a final recording media (FRM) which is able to survive accidents and permit the recovery of voyage information. The FRM can be a fixed unit on the vessel or a floating unit that is connected to an EPIRB to allow for early detection in the event of an accident.
The best way to make sure that a vdr is operating properly is to include its use in every bridge crew’s drills and training exercises. The data saved can be used to determine areas that require training and to enhance bridge procedures and operational safety.
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