Yamato-1

Yamato-1 is a ship built in the early 1990s by Mitsubishi Heavy Industries, [Ltd.] at Wadasaki-cho Hyogo-ku, Kobe. It uses magnetohydrodynamic drives driven by liquid helium-cooled superconductors and can travel at.
Yamato-1 was the first working prototype of her kind. It was completed in Japan in 1991, by the Ship & [Ocean Foundation]. The ship, which includes two magnetohydrodynamic thrusters, which have no moving parts, was first successfully operated in Kobe harbour in June 1992.
An MHDD works by applying a magnetic field to an electrically conducting fluid. The electrically conducting fluid used in the MHD thrusters of Yamato-1 was seawater.
In the 1990s, Mitsubishi built several prototypes of ships propelled by MHDD systems. Despite projected higher speeds, these ships were only able to reach speeds of 15 km/h due to constraints imposed by the weight of the superconducting magnets, and the relatively low system efficiency of 15%.
Afterwards, Yamato-1 was on display at the Kobe Maritime Museum, until it was demolished in 2016.