cover a broader area. >> reporter: it's a slow going process because they are pretty much flying blindly because they don't know what's at the bottom of the sea floor. >> and they also seem to be testing the limits of the device too. i would love for you to ask james, we were expecting 16 hours down, two hours of mapping, we were looking at a 24-hour period, but they have had some technical issues? >> reporter: yes, they're having those technical issues on that 24 hours of going down. that's part of the deal because the reason why it takes so long is because it's so deep, right? >> theyer're planning extremely long distances. there's a lot of interconnected