VM reactor


The VM reactor is type of various series of nuclear pressurized water reactors. They were used singly or in pairs to power the Soviet Navy's submarines.
It was developed by .
In December 2025, it was reported that a ship called the MV Ursa Major that sunk near Spain in 2024 was carrying two VM-4SG reactors intended for North Korea. North Korea has claimed to be completing a nuclear submarine.

Series