Performance Standards for Ship Voyage Data Recorders (VDRs)

1 PURPOSE

The purpose of a voyage data recorder (VDR) is to maintain a store, in a secure and retrievable form, of information concerning the position, movement, physical status, command, and control of a vessel over the period leading up to and following an incident having an impact thereon. Information contained in a VDR should be made available to both the Administration and the shipowner. This information is for use during any subsequent investigation to identify the cause(s) of the incident.

2 APPLICATION

A VDR with capabilities not inferior to those defined in these performance standards is required to be fitted to ships of classes defined in SOLAS Chapter V, as amended.

3 DEFINITIONS

• Voyage data recorder (VDR) means a complete system, including any items required to interface with the sources of input data, for processing and encoding the data, the final recording medium in its
• capsule, the power supply, and a dedicated reserve power source.
•  The sensor means any unit external to the VDR, to which the VDR is connected, and from which it obtains data to be recorded.
•  Final recording medium means the item of hardware on which the data is recorded such that access to it would enable the data to be recovered and played back by use of suitable equipment.
•  Playback equipment means the equipment, compatible with the recording medium and the format
  used during recording, employed for recovering the data. It includes also the display or hardware and software that is appropriate to the original data source equipment.1
• A dedicated reserve power source means a secondary battery, with suitable automatic charging arrangements, dedicated solely to the VDR, of sufficient capacity to operate it.

 OPERATIONAL REQUIREMENTS

1. General

•  The VDR should continuously maintain sequential records of preselected data items relating to the status and output of the ship’s equipment and command and control of the ship.
• To permit subsequent analysis of factors surrounding an incident, the method of the recording should ensure that the various data items can be co-related in date and time during playback on suitable equipment.
• The final recording medium should be installed in a protective capsule which should meet all of the following requirements:
  1 be capable of being accessed following an incident but secure against tampering;
  2 maximize the probability of survival and recovery of the final recorded data after any incident;
  3 be of highly visible colour and marked with retro-reflective materials; and
  4 be fitted with an appropriate device to aid location.
• The design and construction, which should be in accordance with the requirements of
  international standards acceptable to the Organization.
• Playback equipment is not normally installed on a ship and is not regarded as part of a VDR for the purposes of these performance standards.

2.General requirements, methods of testing and required test results.

• The minimum selections of data items to be recorded by the VDR are specified in the above section, additional items may be recorded provided that the requirements for the recording and storage of the specified selections are not compromised.
• The equipment should be so designed that, as far as is practical, it is not possible to tamper with the selection of data being input to the equipment, the data itself nor that which has already recorded. Any attempt to interfere with the integrity of the data or the recording should be recorded.
• The recording method should be such that each item of the recorded data is checked for integrity and an alarm given if a non-correctable error is detected.

3.Continuity of operation

• To ensure that the VDR continues to record events during an incident, it should be capable of operating from the ship’s emergency source of electrical power.
• If the ship’s emergency source of electrical power supply fails, the VDR should continue to record Bridge Audio from a dedicated reserve source of power for a period of 2 h. At the end of this 2 h period, all recording should cease automatically.
• The recording should be continuous unless interrupted. The time for which all stored data items are retained should be at least 12 h. Data items that are older than this may be overwritten with new data.

4. Data items to be recorded

• 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.
• 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.
• 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.
• Heading

As indicated by the ship’s compass.

• Bridge Audio

One or more microphones positioned on the bridge should be placed so 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.

• Communications Audio
  VHF communications relating to ship operations should be recorded.
•  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 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.
• Echosounder
  This should include depth under the keel, the depth scale currently being displayed, and other status information where available.
• Main alarms
  This should include the status of all mandatory alarms on the bridge.
• Rudder order and response
  This should include the status and settings of the auto-pilot if fitted.
• Engine order and response
  This should include the positions of any engine telegraphs or direct engine/propeller controls and feedback indications, if fitted, including ahead/astern indicators. This should also include the status of bow thrusters if fitted.
• Hull openings status
  This should include all mandatory status information required to be displayed on the bridge.
• Watertight and fire door status
  This should include all mandatory status information required to be displayed on the bridge.
• 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.

• 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.

5. OPERATION

The unit should be entirely automatic in normal operation. Means should be provided recorded data may be saved by an appropriate method following an incident, with minimal interruption to the recording process.

6. INTERFACING

Interfacing to the various sensors required should be in accordance with the relevant international interface standard, where possible. Any connection to any item of the ship’s equipment should be such that the operation of that equipment suffers no deterioration, even if the VDR system develops faults.