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A VDR or voyage data recorder is an instrument installed on a ship to continuously record critical Information related to the operation of a vessel.
It consists of a recording system for a period of at least last 48 hours which is continuously overwritten by the latest data. This recording is recovered and made use of for various purposes, especially for investigation in the events of accidents.
Purpose/benefits of VDR

VDR data can be used for :
1. Accident investigations
2. Response Assessment
3. Training support
4. Promotion of best practices
5. Reduction of insurance cost
There are various sensors placed on bridge of the ship and on prominent location from which the required data is continuously collected. The VDR has to be very flexible in order to be interfaced with the existing equipment and sensors for recording of relevant data.
The unit should be entirely automatic in normal operation.
Means are provided whereby recorded data may be saved by an appropriate method following an incident, with minimal interruption to the recording process.
The data collected by VDR is digitalized, compressed, and is stored in a protective storage unit which is mounted in a safe place. This tamper-proof storage unit can be a retrievable fixed or floating unit connected with EPIRB for early location in the event of an accident.



Data Management Unit: This data comprises of voices, various navigational parameters, ship location, etc. are fed to a unit called Data management unit. The data collected by the Data Management Unit is digitized, compressed, and is stored in a specified format in two protective storage units (called “Final Recording Medium”) which are mounted in a safe place. A copy of the data is also recorded in a hard drive housed in the data management unit.


Audio Module: It consists of an audio mixer for recording audio from microphones placed in the wheelhouse, bridge wings, ECR and various other locations. VHF audio signals are also interfaced with this unit.
Bridge Audio should be recorded through the use of at least two channels of audio recording. Microphones positioned outside on bridge wings, should be recorded on at least one additional separate channel.
VHF Communications audio VHF communications relating to ship operations should be recorded on an additional separate channel to those referred to in point above.


Final Recording Medium: The final recording mediums, also sometimes called VDR CAPSULES, comprises of two independent recording units (fixed and float-free) and an long term medium.
a) Fixed recording medium:
 Should record data for at least 48 Hrs which is continuously overwritten with new data.
 should maintain the recorded data for a period of at least two years following termination of recording.
 data should be electronically tamper-proof
This fixed tamper-proof electronic storage medium is encased in a protecting casing. A fixed VDR Capsule is capable of withstanding heavy weather, collisions, fires and pressure conditions even when a ship is at a depth of several meters in water. This unit is fixed with an underwater locator which can be used to retrieved in case of sinking of the ship.
Properties of Final Recording Unit:
 Highly visible color
 Can withstand temp. up to 1100ºC
 Can sustain deep sea pressure of 6000 m
 Electronically tamper-proof data
 Easily accessible / Float-free
b) Float-free recording medium;
 data recorded for at least 48 Hrs and continuously overwritten with new data
 should maintain the recorded data for a period of at least six months following termination of recording;
 data should be electronically tamper-proof
or floating unit with an in-built EPIRB for early location in the event of accident.
C) Long-term recording medium.
 Data recorded for 30 days / 720 Hrs and continuously overwritten with new data
 be capable of being accessed from an internal, easily accessible area of the ship;


Remote Alarm Module: This is a small panel connected to the Data Management Unit that will sound an audio-visual alarm should any error or fault develop in the equipment or if the sensor inputs are missing.


Replay Station: The VDR should provide an interface for downloading the stored data and playback the information to an external computer. The interface should be compatible with an internationally recognized format, such as Ethernet, USB, FireWire, or equivalent.
A playback software should be provided with VDR with the capability to to download the stored data and play back the information. The software should be compatible with an operating system available with commercial off-the-shelf laptop computers and where non-standard or proprietary formats are used for storing the data in the VDR, the software should convert the stored data into open industry standard formats.


VDR installed after 1st July, 2014 must record, in addition to, or alternately, following data:


       Additionally, the following requirements shall be fulfilled by the VDRs installed after 01st July 2014:
RADAR -Recording of the main displays of both ship's radar installations as required by SOLAS regulations.
AIS- All AIS data should be recorded .
ECDIS display in use at the time as the primary means of navigation.
Rolling Motion - VDR should be connected to an electronic inclinometer if installed
Configuration data: In addition to the data items, a data block defining the configuration of the VDR and the sensors to which it is connected should be written into the final recording medium during the commissioning of the VDR.
Electronic logbook: Where a ship is fitted with an electronic logbook in accordance with the standards of the Organization the information from this should be recorded.

An S-VDR (Simplified VDR) is the same as a VDR. There is no principle difference between a VDR and an S-VDR except the amount of information required to be recorded by S-VDR is less.



The following vessels are required to carry a VDR:
• All Passenger ships and Ro-Ro passenger ships
• Ships of 3,000 GT and upwards constructed on or after 1 July 2002.
The following vessels are required to carry an S-VDR:
• Ships over 3,000 GT constructed before 1 July 2002



S-VDR – FAQs (Additional Material)


Should a "fixed" or "float-free" data storage capsule be used?
There is no Type Approved float-free solution currently available and there are varying views on which solution would be most easily retrieved. Indications are that both options are similarly priced.

To what degree does the choice of S-VDR depend on the make of the existing bridge equipment?
The technical specification of the S-VDR has been determined with the express aim of maximising the connectivity with other equipment. The choice of S-VDR can therefore bebased with emphasis on the functionality of the particular S-VDR and the worldwide service support available.

What benefits can be expected from fitting S-VDR?
The operational experience gained from ships equipped with VDR has been well recorded over many years and in summary confirm the positive benefits particularly relating to accident investigation, training and monitoring, assessment of response to safety and environment emergencies, promoting best practice and accident prevention and reduction in insurance losses.
VDRs have also proved invaluable to ship owners as a management tool in analysing hazardous incidents and bridge team procedures. Additionally VDR recordings have provided irrefutable evidence in pollution incidents as well as providing an indisputable record of a Master's action. There have also been a number of instances where disclosure of VDR recordings precluded court actions with the subsequent significant savings in costs.

Can the recorded data be accessed remotely?
Remote access to data is not a requirement of the IMO but a limited number of manufacturers do offer this facility as an option. Kelvin Hughes “MantaDigital™ S-VDR” has the capability of being interrogating through GSM or satellite communications from the shore. This optional feature also allows onboard technical problems to be diagnosed remotely, enabling spares or other support to be arranged in advance of the ship’s arrival in port.

What time period can be recorded?
The IMO requires a minimum of 12 hours recording but most manufacturers provide larger storage options often with removable media, which may be used as a management and training tool. This latter option sometimes referred to as a “white-box”, has found favor in the past where ships’ staff are able to retain a record of an event without disturbing the main (mandatory) data contained within the S-VDR.


How is the performance of the equipment monitored?
The IMO Performance Standard for S-VDR requires a built-in the test facility to be provided to allow for continuous monitoring of the performance of the equipment. An audible and visual alarm is automatically triggered in the event of a malfunction of the S-VDR.


How and where can the data be replayed?
Playback facilities are offered by all manufacturers, usually free of charge, as part of the S-VDR package. This enables incident analysis to be undertaken onboard, ashore, and in a Court of Law.


Who can carry out annual performance checks?
All maintenance, service, and commissioning of S-VDR equipment must be carried out by engineers approved by the manufacturer concerned. This may be delegated to a nominated service agent although some manufacturers, such as Kelvin Hughes, have the added advantage of a well-established and proven worldwide support network with factory-trained engineers located in key ports.


Can an S-VDR be installed whilst the vessel is in service?
In the majority of cases, the installation of an S-VDR can be carried out whilst the vessel is in service. The majority of the work centers around the running of cables for microphones on the bridge and the collection of data from a number of sources. The only restriction on installing during service is when it may become necessary to weld fixings or cut cable penetrations (hot-work) on vessels carrying hazardous cargo e.g. Tankers and gas carriers.


How long does installation & commissioning take?
A typical installation, which would include cable running, mounting of units, termination of cables, and commissioning is estimated to take 5/7 days with two engineers. If preparatory work is completed in advance with the running of cables and provision of foundations for units then termination and commissioning are estimated to take 3 days.



How will compliance be enforced and monitored?
Compliance with Carriage Requirements for S-VDR will be enforced by the appropriate Flag State and Port Control authorities may also prevent vessels from operating who do not have a suitably working S-VDR.

What Type of Approval or Classification Certification is necessary?
All S-VDR equipments fitted to satisfy IMO requirements must be Type Approved.
Kelvin Hughes is the first to receive Type Approval for its MantaDigital™ S-VDR through QinetiQ, the UK government nominated testing organisation. Other manufacturers are following and submitting equipment for test to QinetiQ and other test organisations, including the German testing house, BSH. Individual Classification Societies can endorse Type Approved equipment by reference to the results obtained by the test organisation.

What are the requirements?
IMO through MSC at its 79th session in December 2004 agreed the following amendment to SOLAS Chapter V Regulation 20
To assist in casualty investigations, cargo ships, when engaged on international voyages, shall be fitted with a VDR, which may be a simplified voyage data recorder (S-VDR) as follows:

  •  in the case of cargo ships of 20,000 gross tonnage and upwards constructed before 1 July 2002, at the first scheduled dry-docking after 1 July 2006 but not later than 1 July 2009;

  • in the case of cargo ships of 3,000 gross tonnage and upwards but less than 20,000 gross tonnage constructed before 1 July 2002, at the first scheduled dry-docking after 1 July 2007 but not later than 1 July 2010; and

  •  Administrations may exempt cargo ships from the application of the requirements of sub-paragraphs 1 and 2 when such ships will be taken permanently out of servicewithin two years after the implementation date specified in sub-paragraphs 1 and 2 above.


To what types of vessels does the Carriage Requirement apply?
All vessels involved in international trade over 3,000 tons gross tonnage will be affected by the requirement (except where an exemption is granted by the flag state)

Will fitting S-VDR impact on insurance premiums?
A Marine Underwriter's Perspective
There is no doubt, that the shipping industry can learn a lot from the world of Aviation and this is certainly a point of view held by eminent personages such as Lord Carver and Lord Donaldson. The lessons learned from, “black-box” information following air crashes has obviously done a lot to improve the safety in this industry.


The lessons learned have also given the operators data to enable them to reduce the human element proportion of air disasters. So how can anyone argue against a similar initiative in the Marine world?
As underwriters, we can see the potential advantages that VDRs will bring in reducing the insurance risks.
There is always room for improvement, and, as lessons are learned from VDR playbacks ship operators will be able to respond with meaningful loss prevention actions, which will have a beneficial effect on their insurance results.
VDRs will also provide a reliable and unbiased witness at times of accidents involving other parties. Here again, VDR evidence will do a lot to reduce legal costs and the sterile wrangles about who is to blame.

Is the recorded data recognized as legal evidence?
Yes - extensively, there have been a number of instances already experienced where the disclosure of the existence of VDR recorded data has precluded court action. Clearly, there is an advantage in the situations where systems are installed with the additional removable memory, sometimes referred to as the "white-box".

In the event of an incident - who owns the recording?
"Ownership and recovery" (Abstracts of IMO FSI Sub - Committee 9)
Recovery of VDR
In the case of a non-catastrophic accident, recovery of the memory should be straightforward. This action will have to be taken soon after the accident to best preserve the relevant evidence for use by both the investigator and the shipowner. As the investigator is very unlikely to be in a position to instigate this action soon enough after the accident, the owner must be responsible, through its onboard standing orders, for ensuring the timely preservation of this evidence in this circumstance.

In the case of abandonment of a vessel during an emergency, masters should be instructed, where time and other responsibilities permit, to recover the memory and remove it to a place of safety and to preserve it until it can be passed to the investigator.
In the case of a catastrophic accident, where a vessel has sunk and the data has not been retrieved prior to abandonment, a decision will need to be taken by the Flag State in consultation with any other substantially interested states on the viability of recovering the protective capsule against the potential use of the information. If it is decided to recover the capsule, the investigator should be responsible for its recovery. The possibility of the capsule having sustained damage must be considered and specialist expertise will be required to ensure the best chance of recovering and preserving the evidence. In addition, the assistance and co-operation of the owners, insurers and the manufacturers of the VDR and those of the protective capsule may be required.
Custody of VDR/data
In all circumstances, during the course of an investigation, the investigator should have custody of the original VDR data, perhaps in the form of the whole or part(s) of the VDR itself, in the same way as he has custody of other records or evidence under the Code for the Investigation of Marine Casualties and Incidents.
Ownership of VDR/data
The shipowner will, in all circumstances and at all times, own the VDR and its data.
Read-out of VDR/data
In all circumstances the responsibility to arrange downloading and read-out of the data from the recovered memory in whatever form should, in the first instance, be undertaken by the investigator who should keep the shipowner fully informed. Additionally, especially in the case of a catastrophic accident where the memory may have sustained damage, the assistance of specialist expertise may be required to ensure the best chance of success.
Access to the data
Although the investigator will have custody of the original VDR memory in whatever form for the duration of the investigation, a copy of the data must be provided to the shipowner in all circumstances.
Further access to the data will be governed by the applicable domestic legislation of the flat state, coastal state and the lead investigating state as appropriate and the guidelines given in the Code for the Investigation of Marine Casualties and Incidents.


What are the key factors to be considered when selecting an S-VDR?
 Is the equipment type-approved?
 Does the supplier have a proven track record?
 Does the supplier offer worldwide support?
 Can the supplier guarantee to fit in time to meet agreed deadlines?
 Will the fitting delay the vessel’s operation?
 What does the price include?
 Is there a fixed price package?

 Does the supplier understand interfacing with marine bridge equipment?
 What additional options are available/provided?
 Does the supplier have an established customer base?
 Does the supplier have a reference list?
 Will the supplier be here in the future to support the system?
 Does the equipment offer all the facilities that may be required?

What is the typical price for an S-VDR system?
These vary from manufacturer to manufacturer and are also dependent upon the degree of sophistication demanded. It is suggested that a budget of up to US$50k be allocated for a complete fit.

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