implode, too. >> as we talk about it imploding, it wouldn't necessarily completely implode and disintegrate but it would damage the bluefin enough that it would be inoperable? >> anything with an air pocket is going to get crushed. not only crushed but once it gets crushed it explodes outwards because of the incredible violence of that. it can take out the vehicle without too much trouble at all. >> with that consideration, what then -- how do they factor that into when they decided to go deeper than they originally thought? from 4500 meters to 5,000 meters. is there a big difference there? >> there's a big difference. they have a way offed a justing the software and looking at the components. i'm sure they built big margins in the safety of that vehicle so they could stretch their operating depth out a little bit. >> they wouldn't be doing it unless they knew -- >> i'm sure the teams are positively share that it's safe to do. >> at we one moment what do you think the biggest challenge is for the teams as they consider putting the bluefin in and for