Losses in WW1

Orfordness was a 2,790 GRT steam cargo ship completed in 1906 by Ropner & Son for Gate Steamship Co. Ltd. as Blackfriargate. From 1918 she was owned by English Steamship Co. Ltd. and managed by Letricheux & David Ltd. She was sunk on 20 July 1918 by torpedo fired by German submarine U-60 at position 50° 24' N, 05° 11' W - approximately 2.5 nautical miles West by North of Newquay. She was en route from Rouen to Barry in ballast.

Origen was a 3,544 GRT steam cargo ship completed in 1918 by Caledon Shipbuilding & Engineering Co. Ltd for Booth Steamship Co. Ltd. She was sunk on 1 July 1918 by torpedo fired by German submarine U-86 at position 37° 28' N, 08° 20' W - approximately 115 nautical miles West by South of Ushant. She was en route from London to Oporto and Brazil.

Oriole was a 1,489 GRT steam cargo ship completed in 1914 by Ailsa Shipbuilding Co. Ltd. for General Steam Navigation Company Ltd. She was sunk on 30 January 1915 by torpedo fired by German submarine U-20 approximately 20 nautical miles North-West of Cap d'Antifer. She was en route from London to Le Havre with a general cargo.

There were no survivors

Orissa was a 5,317 GRT steam passenger/cargo ship completed in 1895 by Harland & Wolff, Ltd. for Pacific Steam Navigation Company. She was sunk on 25 June 1918 by torpedo fired by German submarine UB-73 at position 56° 20' N, 07° 20' W - approximately 21 nautical miles South-West by West of Skerryvore Rock. She was en route from Liverpool to Philadelphia in ballast.

Oronsa was a 7,970 GRT steam passenger/cargo ship completed in 1906 by Harland & Wolff, Ltd. for Pacific Steam Navigation Company. She was sunk on 28 April 1918 by torpedo fired by German submarine U-91 approximately 12 nautical miles West of Bardsey Island, St. George's Channel. She was en route from Talcahuano and New York to Liverpool with a general cargo.

Orsova was a 12,036 GRT steam passenger/cargo ship (ref) completed in 1909 by J. Brown & Co. Ltd. for Orient Steam Navigation Co. Ltd. She was damaged on 14 March 1917 by a mine laid by German submarine UC-68 approximately 3 nautical miles East by South of Eddystone. She was beached at Cawsand Bay in a sinking condition but was towed to Devonport and patched before being taken to Liverpool for repairs that were not completed until September 1918 after which she continued in service until 1936 when she was broken up. At the time of the attack she was en route from London to Devonport with a cargo of government stores.

Ortolan was a 1,717 GRT steam passenger/cargo ship completed in 1902 by Caledon Shipbuilding & Engineering Co. Ltd. for General Steam Navigation Co. Ltd. She was sunk on 14 June 1917 by torpedo fired by German submarine U-82 at position 48° 09' N, 09° 45' W - approximately 100 nautical miles West-South-West of Bishop Rock. She was en route from Palermo to London with a general cargo.

Ortona was a 5,524 GRT steam cargo ship completed in 1916 by J. L. Thompson & Sons, Ltd for The Gulf Line, Ltd. and managed by Furness, Withy & Co. Ltd. She was sunk on 21 June 1917 by torpedo fired by German submarine U-50 at position 49° 10' N, 09° 51' W - approximately 140 nautical miles Sout-South-West of Fastnet. She was en route from Philadelphia to London with a general cargo.

Oslo was a 2,296 GRT steam passenger/cargo ship completed in 1906 by Earle's Shipbuilding & Engineering Co. Ltd. for T.Wilson, Sons & Co. Ltd. From 1917 she was owned by Ellerman’s Wilson Line Ltd. She was sunk on 21 August 1917 by torpedo fired by German submarine U-87 approximately 15 nautical miles East by North of the Out Skerries, Shetland Islands. She was en route from Trondheim to Liverpool with a cargo of copper ore.

Ostpreussen was a 1,755 GRT steam cargo ship completed in 1901 by F. Schichau of Danzig for M.Cohn & Sohn. By 1914 she was in the possesion of the British Admiralty and managed by Witherington & Everett. She sank on 26 November 1917 after striking a mine laid by German submarine UC-11 approximately 1.5 nautical miles East of the Shipwash light vessel. She was en route from Sunderland to London with a cargo of coal.