HSwMS Sjöormen

Several ships of the Swedish Navy have been named HSwMS Sjöormen, named after the sea serpent:


 * HSWMS Sjöormen (1941) was a Sjölejonet-class submarine launched in 1941
 * HSWMS Sjöormen (Sor) was a Sjöormen-class submarine launched in 1967 and sold to Singapore in 1997