Voyage data recorder

It then digitizes, compresses and stores this information in an externally mounted protective storage unit.

The protective storage unit is a tamper-proof unit designed to withstand the extreme shock, impact, pressure and heat, which could be associated with a marine incident (fire, explosion, collision, sinking, etc.).

Although the primary purpose of the VDR is for accident investigation after the fact, there can be other uses of recorded data for preventive maintenance, performance efficiency monitoring, heavy weather damage analysis, accident avoidance and training purposes to improve safety and reduce running costs.

[1] A simplified voyage data recorder (S-VDR), as defined by the requirements of IMO Performance Standard MSC.163(78), is a lower cost simplified version VDR for small ships with only basic ship's data recorded.

The information recorded in the unit(s) (sometimes also called the ship's black box) may include the following information: Data marked with * may not be recorded in S-VDR, except Radar and Echo Sounder if data and standard interfaces available.

The protective capsule of a voyage data recorder on M/V Barfleur
This image shows the AMI Marine ltd Float Free Capsule used on ships to store a minimum of 48 hours of recorded data. if the vessel sinks the capsule case (white) will open and release the Yellow capsule from inside, this capsule will then float to the surface and emit a distress signal to alert shore side authorities.
A fixed Data Capsule of VDR mounted on a container ship