The model builders at Japan's Yokosuka Dry Docks built a model of the Federation starship Enterprise as a remote controlled submarine. They used Polarlights 1/350 scale Starship Enterprise model kit as a base. The ship is water-tight, utilizing Pump Jet 3D active dive control method and can zip around underwater with lights.
Buck and Ryan should love this...
Be sure to head over to YDD’s YouTube page to see more of their underwater spaceship creations, including the Millenium Falcon, USS Voyager and highly appropriate Battleship Yamato.