Grand Admiral a naval rank in one of the highest in the several European navies that use this system, what system are they using?
Grand admiral Grand admiral is a historic naval rank, the highest rank in the several European navies that used it. It is best known for its use in Germany as "Großadmiral". A comparable rank in other navies is that of fleet admiral.
Chief of Naval Operations (South Korea) The Chief of Naval Operations of the Republic of Korea (Korean: 대한민국 해군참모총장 , Hanja: 大韓民國海軍參謀總長 ), shorten as CNO, is the professional head of the Republic of Korea Navy (ROKN) since its foundation in 1948, originally held by a vice admiral, then by an admiral since 1968.