you want it to be found by rescuers or recovery team. it s designed to be unique and not readily found in nature. thomas, the ping detector that the chinese have on board is designed for use in shallow water, water as deep as 15,000 feet in these areas. is it possible to pick up a pulse that deep with this equipment? well so say it s designed to work in shallow water. that means the sensor only goes into shallow water. the ability for sound to propa investiga propagate and move through the water is very complex. there was a discussion about the water column and layers. that s very important how sound moves. so we would say that it is possible, but it s very unlikely. it would have to be the perfect set of conditions to have any frequency like 37.5 propagate