5.4 Data Items to be Recorded
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Resolutions - Assembly - IMO Resolution A.861(20) - Performance Standards for Shipborne Voyage Data Recorders (VDRs) - (adopted on 27 November 1997) This Resolution applies to VDRs installed before 01 July 2014 - Annex - Recommendation on Performance Standards for Shipborne Voyage Data Recorders (VDRs) - 5 Operational Requirements - 5.4 Data Items to be Recorded

5.4 Data Items to be Recorded

  5.4.1 Date and Time

Date and time referenced to UTC, should be obtained from a source external to the ship or from an internal clock. The recording should indicate which source is in use. The recording method should be such that the timing of all other recorded data items can be derived on playback; with a resolution sufficient to reconstruct the history of the incident in detail.

  5.4.2 Ship's Position

Latitude and longitude, and the datum used, should be derived from an electronic position-fixing system (EPFS). The recording should ensure that the identity and status of the EPFS can always be determined on playback.

  5.4.3 Speed

Speed through the water or speed over the ground, including an indication of which it is. derived from the ship's speed and distance measuring equipment.

  5.4.4 Heading

As indicated by the ship's compass.

  5.4.5 Bridge Audio

One or more microphones positioned on the bridge should be placed such that conversation at or near the conning stations, radar displays, chart tables, etc., are adequately recorded. As far as practicable, the positioning of microphones should also capture intercom, public address systems and audible alarms on the bridge.

  5.4.6 Communications Audio

VHF communications relating to ship operations should be recorded.

  5.4.7 Radar Data, Post-display Selection

This should include electronic signal information from within one of the ship's radar installations which records all the information which was actually being presented on the master display of that radar at the time of recording. This should include any range rings or markers, bearing markers, electronic plotting symbols, radar maps, whatever parts of the SENC or other electronic chart or map that were selected, the voyage plan, navigational data, navigational alarms and the radar status data that were visible on the display. The recording method should be such that, on playback, it is possible to present a faithful replica of the entire radar display that was on view at the time of recording, albeit within the limitations of any bandwidth compression techniques that are essential to the working of the VDR.

  5.4.8 Echo Sounder

This should include depth under keel, the depth scale currently being displayed and other status information where available.

  5.4.9 Main Alarms

This should include the status of all mandatory alarms on the bridge.

  5.4.10 Rudder Order and Response

This should include status and settings of auto-pilot if fitted.

  5.4.11 Engine Order and Response

This should include the positions of any engine telegraphs or direct engine/propeller controls and feedback indicators, if fitted, including ahead/astern indicators. This should also include status of bow thrusters if fitted.

  5.4.12 Hull Opening Status

This should include all mandator status information required to be displayed on the bridge.

  5.4.13 Watertight and Fire Door Status

This should include all mandatory status information required to be displayed on the bridge.

  5.4.14 Accelerations and Hull Stresses

Where a ship is fitted with hull stress and response monitoring equipment, all the data items that have been pre-selected within that equipment should be recorded.

  5.4.15 Wind Speed and Direction

This should be applicable where a ship is fitted with a suitable sensor. Either relative or true wind speed and direction may be recorded, but an indication of which it is should be recorded.


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