The cableship Alert was launched in 1918 after being constructed by Messrs Swan, Hunter and Wigham Richardson.
Along with the Cableship Monarch the Alert was designed to operate in shallow waters only. Her gross tonnage was 941 and the 105 horse power engines were able to drive the twin-screws up to a maximum speed of 10.5 knots. The ship was constructed from steel and had a clipper stem with cable sheaves and a cruiser type stern. Originally she was coal-fired, but was converted to oil fuel in 1920. Three cable tanks of 10160 cubic feet total capacity were fitted. These could hold up to 81 miles of single core cable, 54 of 4 core or 35 of 6 or 7 core.
As a result of other demands during World War I she had to be equipped with the very old and almost broken down cable gear from the first Cableship “Alert”. This largely impeded her operational capabilities until it was replaced in 1921 by more modern gear.
After 27 years service, on 24 February 1945, shortly before VE Day, the Alert was when she was torpedoed & sunk while repairing the Dumpton Gap – La Panne cable in the Straits of Dover. All 59 hands—officers and men— were lost.