Dai_Farr: nice explanation ... almost makes me nostalgic for the old ASW days.
Originally Posted by
Dai_Farr
Pontius Navigator has described sound channels and a peculiar type of transmission path called Convergence Zone in earlier posts. The difficulty I see in the path sound takes in the case of this suspected sonic locator beacon, is that the beacon is on the seabed, whereas any receiver could well be at least two boundary layers up. What with refraction and reflection of the ray, this adds a further difficulty in homing in on any such signal. Getting source and receiver in the same layer would be a huge help.
I think that if the receiver were below the axis of the deep sound channel, best hopes for detection would be realized. A few thousand feet deep, maybe, depending on the BT drop that day.
For Pontius: my opinion is that there isn't enough acoustic energy for the wavelength used to get a CZ path. I'll accept correction on that if I've forgotten a few more bits of "Acoustics for ASW Folks" than I had realized.
EDIT: Agree with Pontius about not ruling out anything, Bill S's point about direction of propagation considered.