pick out individual pieces of debris but maybe something that's interesting and at that point you have to deploy other pieces of equipment that can go deeper, things like remotely operated vehicles. those go down to the bottom. they're tethered to the surface via cable and eventually a robot submarine you can drive around from the surface and it will either survey the bottom with sound or look directly with lights and see if it can find more debris that way. >> it's a tough thing. i've seen the images they look on the first scans and they look like amorphous shapes. you have to use magic as much as anything else. this is uncomfortable but air france, two years before they found that plane but they knew where it went down in general. is there a chance this plane will never be found? >> i think there that's a significant possibility, and i'm obviously loathe to say, that very disappointing for the families involved. but when the ocean reclaims things as it so often does, very