me that this is a game of inches. something very delicate. that if you're going to go down and collect a black box you can't just go down, and zip right back up with it? >> no, that is very true. >> reporter: we have a black box right here already in the claw of this vehicle. and just show me o-- it is a vey delicate operation just to put it into the basket that we need to put it in to carry it back up to the surface. and while you're watching this, notice how the water is moving and how cloudy it is here. it is sediment that can be a problem if you stir it up. it is almost like blowing into a handful of flour. you would be blind for a while. and every motion like this, you would just have to stop and wait for the sediment to stop before you can start back over again. and this is right in front of our face here, still it is not an easy thing to do, is it?