How realistic is this really?

[Gargamel]

1) As mentioned, they are actually quite tall, and with 14-15ft above water, there is about 40+ ft of draft. This is similar, or at leat approaching, in ratio to a oil rig, or even an iceberg. You don't see them rolling around that much. I admit, at first glance, it looks unstable, but the more I thougth about it, the more i realized it would be a very stable platform. And as mentioned in other threads, it runs on Diesel turbines, with global range, not batteries.

2) think those were outlawed many years ago

3) Check the scoring thread, as mentioned in the DARPA mission specs, it is inteded to be OVERT, not Covert. That's why the ping penalty is so low. It is low enough to be basically non existant.

And shooting one of these in international waters would not be the same as shooting down a UAV that has penetrated your airspace, this would be more akin to shooting down a spy satellite because it crossed over your country. International space/waters are just that, international. Sinking one of these would be tantamount to an act of war. The russians used to do this exact thing during the cold war with their spy trawlers. So what if the drone is following your sub, it's actually not doing anything harmful to you.