Originally Posted by
bimmerdriver
AFAIK, the Bluefin can carry either an edgetech side scan sonar that operates at 120-410 kHz or a reson multibeam that operates at 400 kHz. They are probably using the side scan because it covers a wider area. The range of this sonar is not so great that there isn't plenty of space for more than one vehicle to operate. It probably comes down to availability.
Regarding the ships, they are presumably searching for surface debris to unambiguously confirm the aircraft went down in the region. Since they haven't found any wreckage (yet), they still don't know with 100% certainty that they are in the crash location.
I presume the Bluefin generates a finely detailed map of the bottom. From a search perspective, what are the benefits of such detail at this point rather than use a more powerful transmitter aboard a ship, such as the survey vessel Echo. At 4K meters, can a surface ship image a structure like a 777 debris field on the bottom? If so, seems to me that the sweep area would be significantly larger with a surface vessel and allow a much more rapid search. Is there any difference in the return signal after pinging off an aluminum and steel surface? Once committed to a particular search alternative (ie Bluefin), is it possible to "tune" other sonars to avoid increased noise in the search area?