HMS Actaeon was a modified Black Swan-class sloop built for the Royal Navy during the Second World War.

[1][2] Actaeon was powered by Parsons geared turbines driving two shafts, giving a speed of 19.75 knots[3] She was armed with six QF 4 inch Mk XVI anti-aircraft guns in three dual turrets.

As part of the rearmament for its new Bundesmarine in 1957, the Federal Republic of Germany (West Germany) took over a total of seven Royal Navy ships as training frigates in the development phase of the Federal Navy, which, for the sake of simplicity, were grouped under the generic term of Class 138 school frigates, although they are by no means all identical.

Germany put the Actaeon into service in January 1959 as Hipper for the Mürwik Naval Academy, where the former sloop-of-war was used for cadet training alongside sister ship Graf Spee.

Other ports visited ranged from Reykjavik in the north to Lomé, Togo and from Dar es Salaam, Tanzania in the south to Bangkok in the east.