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.
Admiral of the fleet An admiral of the fleet or fleet admiral (sometimes also known as admiral of the navy or grand admiral) is a military naval officer of the highest rank. In many nations the rank is reserved for wartime or ceremonial appointments. It is usually a rank above admiral (which is now usually the highest rank in peace-time for officers in active service), and is often held by the most senior admiral of an entire naval service.