A bronze waterline model of the Royal Navy porpoise-class submarine HMS Finwhale (SO5).

Width: 48 cm.

Depth: 11 cm.

Height: 7.5 cm.

HMS Finwhale (S05) was the fifth Porpoise-class submarine of the Royal Navy. She was launched on 21 July 1959 and first commissioned on 19 August 1960. During her first commission she went further under the ice than any other submarine at the time. She was recommissioned on 27 January 1964. In March 1965 on her second Arctic patrol she further eclipsed her first ice patrol, penetrating 95 miles into the ice.

The Porpoise class was an eight-boat class of diesel-electric submarines operated by the Royal Navy. This class was originally designated patrol submarines, then attack. They were the first conventional British submarines to be built after the end of World War II. Their design was, in many ways, influenced by the German World War II-era Type XXI U-boats.