Nautilus (Verne) from seawater) is the craft's primary power source for propulsion and other services. "Nautilus" is double-hulled, and is further separated into water-tight compartments. Its top speed is . Its displacement is submerged. In Captain Nemo's own words: "Nautilus" uses floodable tanks in order to adjust buoyancy and so control its depth. The pumps that evacuate these tanks of water are so powerful that they produce large jets of water when the vessel emerges rapidly from the surface of the water. This leads many early observers of "Nautilus" to believe that the vessel is some species of whale, or perhaps a
Jules Verne ATV tests on 13 March and 14 March, ensuring that the CAM could be conducted as a last back-off mechanism should all other systems fail during the docking manoeuvre. Subsequently, the ATV performed two docking demonstration tests called "demo days". These tests consisted of a series of rendezvous with the ISS, and culminated in its final test: an actual docking with the aft port of the "Zvezda" service module on 3 April 2008. The rendezvous were performed by a fully automated system using GPS and optical sensors, including a videometer and telegoniometer. When "Jules Verne" was from the space station, the