Built for the Newcastle-based Cairn Line by Doxford's of Sunderland, Cairndhu and Cairngowan were a pair of identical general cargo steamers launched in 1911. Designed with one deck and constructed from steel throughout, they were registered at 2,561 tons net (3,817 under-deck) although, curiously, Cairndhu's gross tonnage of 4,019 was two tons heavier than Cairngowan's at 4,017. Measuring 370 feet in length with a 51 foot beam, both steamers were driven by a single screw powered from one of their builder's own triple-expansion 3-cylinder engines producing 292nhp.
After only a short service life, the two ships each became casualties of the Great War, with Cairndhu outlasting her sister by just a year. Cairngowan was lost first when she was captured and sunk by gunfire on 20th April 1916. Stopped by the German submarine U69 in the Atlantic about 55 miles northwest of the Fastnet Rock, she was on passage from Liverpool to Newport News, Virginia, in ballast but there was no loss of life when she went down. By comparison, eleven crew were killed when Cairndhu was torpedoed and sunk on 15th April 1917 by the German submarine UB40 whilst she was on passage from the Tyne to Gibraltar with a cargo of coal.