your biggest concern here, he's going to be navigating, using a sonar, right? >> sonar system so that -- the sonar system will tell if there's any major obstacles in the way. the other stuff will be visual. it will be a combination of operating by sonar and by visual through the ports or through a video camera. >> and the sonar is going to give you a range of about how far? >> well, if you're up off the bottom you can see probably 500 meter or so. when you're flat on the bottom it's going to be a very short range, something like five, ten meters. >> i think we were talking yesterday, chris, that, you know, probably 15 hours maybe they could spend either in an rov or something like this? >> yeah that would be a long shift. but certainly -- >> i'm not volunteering for that, just so you know. >> but you know, if you include the time up and down, that's half the time. if you get six or seven good hours on the bottom, that's a pretty good shift with an rov.