The engines were designed to produce 18,000 shaft horsepower (13,000 kW) which was intended to give the ships a speed of 32 knots (59 km/h; 37 mph).

The ships carried 230 t (226 long tons) of coal and 72 t (71 long tons) of fuel oil that gave them a range of 1,850 nautical miles (3,430 km; 2,130 mi) at a cruising speed of 10 knots (19 km/h; 12 mph).

[2] The primary armament of the Aventurier-class ships consisted of four 100-millimeter (3.9 in) guns in single mounts, one on the forecastle, one between the funnels, and two on the quarterdeck, in front and behind the searchlight platform.

[1] Opinâtre was ordered from Dyle et Bacalan and was launched in 1911 with the name of La Rioja at its Bordeaux shipyard.

[2] On 27 May 1915, Opiniâtre and her sister ship Téméraire escorted the armored cruiser Victor Hugo as she transported Vice-Admiral (Vice-amiral) Augustin Boué de Lapeyrère, commander of the 1st Naval Army (1ère Armée Navale), to Taranto, Italy, for a meeting with Admiral Prince Luigi Amedeo, Duke of the Abruzzi (Duca degli Abruzzi), Commander-in-Chief of the Royal Italian Navy (Regia Marina).