By its very nature, a Voyage Data Recorder is an advanced marine tool expertly conceived to collect and administer a wealth of evidence concerning the ship’s onboard operations.
The array of data provided by the VDR is basically the very essence why incident investigations and performance evaluation is feasible. In fact, the VDR data is considered an ideal tool for assessment in respect to the ship’s safety and efficiency.
To amplify its value as a fleet management measure, substantially, the VDR can be associated with the satellite communication system. With this, the information captured by the VDR can be downloaded to shore offices.
The accessibility of the VDR data from trouble ship can be an exceptional aid to the search and rescue teams/authorities. Basically, yielding the relevant and timely data can assist them in organizing for salvage or support from technical specialists ashore.
Such marine recorder can be interfaced with the other vessel board computer systems for retaining and handling the recorded information. In such way, the data can be checked, monitored, or reviewed in real-time on custom-made graphics screens. Or, the VDR data can be replayed for analysis of the ship and its engine performance.
Furthermore, the playback capacity can furnish an invaluable means for scenario-driven Mariners training and education. For example, the captain can replay a specific maneuvering scheme or harbor approach to pinpoint shortcomings and be able to improve practices and decision-making.
The Interface Specifications
The IEC 61996 of the International Maritime Organization implements detailed instructions concerning the prescribed data sets for both VDR and Simplified VDR.
SHIP’s Position. Initially, the latitude and longitude up to a resolution of 0.00001 minutes of arc and the datum utilized. The identification and condition of the source should be documented in order to be recognized during playback.
Date and Time. These details are in reference to the Coordinated Universal Time (UTC). Such is acquired from an origin external to the vessel or from an internal timekeeping device at least once every hour. The capturing of data must pinpoint which origin is in use. The recording approach should be the timing of all other documented data items. As a result, all information can be taken during the playback with a resolution adequate to reassemble the past events of the marine incident in fact.
Heading. The heading of the vessel with a resolution up to 0.1 degrees, as from the vessel’s compass.
Speed. The speed that is through the water or on the ground, up to a resolution of 0.1 knots, with an implication of which is being utilized.
Bridge Audio. Recorded or captured from one or more microphones situated so that the conversations at or nearby the radar displays, chart tables, conning stations, and other workstations can be sufficiently recorded. When practical, the microphones should as well capture the intercom input and output. Also, the public address systems and bridge audible alarms.
Communications Audio. This is the VHF or Very High-Frequency communications that relate to the vessel operations. This involves received and disseminated or translated audio signals. The communications Audio must be separate from the bridge audio.
Further details explained….
Radar/AIS Data. This is virtually the electronic signal data from one of the vessel’s radars. It records all data that are viewed on the master display of such radar during the time of recording. This encompasses range rings, bearing markers, radar maps, electronic plotting signs. Furthermore, any components of the electronic map or chart being selected, navigational data, voyage plan, radar status info and voyage alarms. The recording procedure should be such that it will administer a truthful replica of the entire display of the radar during replay.
Main Alarms. The status of all the IMO mandatory alarms, captured by the bridge audio. And, as a data frame where feasible.
Depth. This specifies the depth beneath the keel, up to a resolution of 0.1 meters, involving the depth scale presently being employed.
Engine Order and Response. This is substantially up to a resolution of 1 rpm, or a pitch of 1 degree. This involves stern and bows thrusters whenever fitted.
Rudder Order and Response. This is basically up to a resolution of 1 degree. Also indicating the settings and status of the vessel’s autopilot.
Watertight and Fire Door Status. This should also encompass all the IMO mandatory status details prescribed to be viewed on the bridge.
Hull Openings (Doors). Specifications are the same with the watertight and fire door status.
Wind Speed and Direction. This is either the relative or true wind, with an implication of which.