container. he said i had to get that information out there because the families of the people who are missing deserve to know what we know but, yes, it could be just a shipping container, nothing to do with that flight. so disappointment with the australian government as well that they seem to be dialing back, all around no progress. the optimism that was here just 24 hours ago, the buzz is now really fading. >> so disappointing to hear because the pings from those black boxes, the batteries are about to die. what are they saying about that? >> reporter: well, they're saying exactly that. we have a window of opportunity here. we've only got a little more than 15 days to find something which we can link back to where that wreckage may be. the challenges, carol, they are huge. not only is it that four hour flight just to get to the target zone which means that planes can only stay over that site for about two hours, it's the depth. three miles deep some of the water around there.