Now that we know of u/w signals having been detected by means yet unknown and that such emissions are likely to be from the DFDR could those with knowledge and expertise please of such- sub surface searches inform us of the acoustic/detection range of these signals.
ps whilst typing the above I just read takata`s post which says 4m, but at 1000m depth. Given the wreckage may be lying at greater depth, what then would the range be.