SS Radaas was a 2524-ton cargo steamship. She was built by and launched in 1890 as Marstonmoor for Moor Lines. She was sold to a Greek company in 1902 and renamed Athos Romanos, before being sold to Danish interests during the First World War and renamed Radaas. She was sunk by the German submarine under the command of Oberleutnant Hans Howaldt on 21 September 1917. She was 18 miles west of Portland Bill en route from Tyne to Bordeaux when the torpedo struck her in the port side.
The wreck lies on a sandy bed at a depth of 30 m at 50°34′13″N3°4′50″W / 50.57028°N 3.08056°W / 50.57028; -3.08056Coordinates: 50°34′13″N3°4′50″W / 50.57028°N 3.08056°W / 50.57028; -3.08056.