[pge]

When I worked for the Navy, we hosted a human-powered submarine race in one of the model basins where we normally tested new ship designs. Anyone could enter but it was mostly university engineering teams. It was great fun to see the homemade designs people came up with and built (and were willing to dive in!) - there some good ones but also some hilariously bad ones. A submarine that can be steered accurately under propulsion is harder to build than a lot of people realize. The most common failure arose from the assumption that a submarine will stay “upright,” forgetting that it can roll in the water (and will unless there is some control surface or ballast preventing it). Thankfully, it was a controlled environment with Navy divers on hand, so we didn’t lose anyone, but a few had to be pulled out.

[hermitcrab]

Sounds cool. Where was that?