uncharted and it's not clear what they might find. oceanographers say it's great for an unmanned sub. >> in all i know doing oceanography for 30 years, the worst thing to do is send a manned vehicle down. everything we learned, if you look at the gulf of mexico oil spill, they were able to fix it with an r.o.v., remote operational vehicle. we have experience with deploying remote operational vehicles that can cut, hold wrenches, they can do things and certainly can bring black boxes up and work 24/7. you are much better off with the remote tools, in my estimation. >> for the families with loved ones on flight 270, reality may be settling in. 40 days after the jet went missing, it might be a very long time before the plane is found.