In response to the following:-
-@UA
-Juste wondering if you could comment about the order of magnitude of the -cost involved in operating such vessel ? Also what would be the typical -mission for this type of equipment ? Telecom cables ? (very) deep offshore -rigs ? scientific ?
Not willing to go into costs at this stage other than to say that the whole spread (vessel, WROV, deep tow sonar & personnel is considerably sub £100k per day.)
Typical workscope for such a sonar spread is pretty much as you state above, scientific, deep wreck search, deep telecoms cables, pipeline route survey, not rig related however at those depths.
-@UA
-I don't know either, whether you can comment on some of the issues?
-Do we even know where the debris field is?
-What's the resolution of the sonar? How easy or difficult is it to distinguish -a piece of 'man-made' debris from the rock next to it?
-It's unlikely the FDR and CVR were thrown clear from the rest of the -wreckage... more likely they're still stuck in some of the aircraft structure. -So much the same question... you're not looking for rectangular boxes, but -for the most likely parts of the wreckage. Can the kind of sonar you mention -find those?
-You obviously would not send a ROV down until you had at least some kind -of target, no?
A working group is currently in place to identify the search area.
Typically, given the length of cable behind the tow vessel (upto circa 10,000m) a series of runs will be made within a box, once the box is complete any targets identified by the sonar passes will then be investigated by the WROV.
It is not a case of differentiating between simply 'black boxes' and rocks, any wreck be it aircraft or ship will leave a debris field, usually over quite a large area. Such an area would be rather obvious and would warrant further investigation with the WROV using both video and hi-res multibeam sonar to map the debris field. Such a hi-res multibeam system can pick out items as small as a coke can.