HMS Acheron (P411) was an Amphion-classsubmarine of the Royal Navy, laid down 26 August 1944, launched 25 March 1947 and completed in 1948. She took part in the Coronation Review of the Fleet to celebrate the Coronation of Queen Elizabeth II in 1953. She carried out 'General Naval Service' around the UK until the end of 1964. For the next 2 years she was loaned to the Canadian Navy. She was decommissioned and broken up in 1972 at the yard of J Cashmore of Newport.
A geomagnetic storm in February 1956, during solar cycle 19, interfered with radio communications and prompted a search for the submarine after it lost radio contact.