>> we all do. >> reporter: this effort will go from searching for survivors to searching for answers. now will come the u.s. navy and ntsb. the navy will be brought in at the end of the week to try to locate the wreckage of the vessel under what could be 15,000 feet of water. they are specifically going to be looking for what is called the voyage data recorder. black box if you will of the ship. to do that, it is like an airplane, it supposedly has a pinger. that pinger should give off a signal to help them locate the wreckage. first they have to listen, then send a submersible down to look and then retrieve the data recorder. there is information to help them figure out why this tragedy happened. john and michelle.