I am personally terrified of submarines, but I think I could handle the SeaBird. The SeaBird is a two-person submersible that can hit 40 mph while underwater. The only catch is that it must be towed by a boat.
The SeaBird has a 400-foot tow line and electric motors that control the craft's depth and its direction. According to the makers of the sub, there is enough oxygen to allow two intrepid explorers three days underwater. Three days is quite some time, and I doubt that anyone would want to stay underwater in even a normal submarine that long. Still, having the option to is nice, as is not having to worry about the sub's engine going out and leaving you stuck in the ocean. The SeaBird may seem like a concept but it is actually available for purchase provided you have $210,000.
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