The 1980’s have marked the history in the maritime industry for having several major marine tragedies with an unsuccessful investigation. This basically has urged the marine field to adopt an advanced technology in ships like VDRs or ship data capsules.
What are protected ship data capsules?
The FRM or that stands for Final Recording Medium for a voyage data recorder should be fully installed in a protected data capsule. Particularly, of either a type of fixed ship data capsule or float-free one. In both cases (fixed and float-free) the equipment must keep the recorded or captured data for a period of at least two years
In both cases (fixed and float-free) the equipment must keep the recorded or captured data for a period of at least 2 years following the termination of recording. And, should be of a highly noticeable color and specified with retro-reflective material. The International Maritime Organization set standards or requirements regarding the data capsule.
The International Maritime Organization set standards or requirements for all ships to follow regarding the installation of data capsule. That, it must be capable of being accessed following an oceanic accident but secure against damage. Also, it must be equipped with an appropriate tool to aid location.
Fixed Ship Data Capsules
With regards to the installation of data capsules that are fixed, survivability or endurance features are specified as follows. These specifications apply to both voyage data recorders and Simplified-VDR.
- Fire – 1100°C for one hour and 260°C for ten hours
- Impact shock – 50g for 11 milliseconds
- Deep-sea immersion and pressure – twenty-four hours at 6.000 meters depth. And, thirty days at three meters depth.
- Penetration – 250 kg mass dropped three meters jolting with
one hundred mm diameter pin
Furthermore, the fixed data capsules must be featured with a release system to assist in recovering underwater by a diver. As well, must be established with an audio underwater beacon along with a battery life of at least thirty days.
Float-Free Ship Data Capsules (Applies to Simplified-VDR)
- Must have flashing light
- The homing transmitter must be operating on 121.5 MHz
- Having the capacity to resolve and transmit position with a minimum of four seconds of arc
- Having a battery life of at least seven days for transmitter
Further Distinctions of a Fixed and Float-Free Ship Data Capsules
Substantially, the selection between the two types of ship data capsules is actually governed by a field of factors. As to fixed data capsule, it is invented for a greater survivability level. In essence, it meets more stringent stipulations for extreme shock, immersion, and fire. Moreover, it has a longer battery life of thirty days.
On the other hand, the float-free ship data capsules can only survive for seven days. It features faster, easier, and lower-cost of recovering the device in case of sinking. Therefore, this eliminates the need for divers or submersible ROV in order to descend to the vessel and recover the data capsule.
However, the float-free ship data capsules do not meet the similar standards for fire resistance. Thus, this could be damaged of the vessel burns. In addition, there may be issues about the capability of the capsule to-float-free liberally if the vessel should roll over. the float-free capsule’s whole system installation might have a higher cost due to the necessary attributes:
- Hydrostatic release mechanism
- Battery replacement
- Cospas-Sarsat frequency testing
- The need of several replacements