On 8 November 1942, while deployed off Oran, Algeria for operation "Torch", "Achates" detected, and attacked the Vichy French submarine , which had sortied to contest the Allied landings in the area. "Achates" attack on "Argonaute", saw the rise of oil to the surface of the sea and huge air bubbles, as well as debris from both inside, and outside the submarine. Following this, at a later point, HMS Westcott made a further attack, hence both ships were credited with her demise.