HMS Acheron (P411) was an Amphion-class submarine of the Royal Navy, laid down 26 August 1944, launched 25 March 1947 and completed in 1948.

It also contained four electric motors each producing 625 horsepower (466 kW) that drove two shafts.

[2] When submerged, it could operate at 3 knots (5.6 km/h; 3.5 mph) for 90 nautical miles (170 km; 100 mi) or at 8 knots (15 km/h; 9.2 mph) for 16 nautical miles (30 km; 18 mi).

[1] Acheron was fitted with ten 21 inches (530 mm) torpedo tubes, one QF 4 inch naval gun Mk XXIII, one Oerlikon 20 mm cannon, and a .303 British Vickers machine gun.

[4] From August to December 1959, It took part in a cruise to South Africa and Pakistan.