During the Second World War the Windsor Castle was requisitioned as a troopship and on 23 March 1943 was sunk by an aerial torpedo off the coast of Algeria.

[1] The continuation of the war until late 1918 led Harland & Wolff to subcontract her building to John Brown & Company.

[1] This gave the Union-Castle Line the two largest ships on that run to provide an alternating service between England and South Africa.

Just aft of the fourth funnel, the ship had a pair of gantry davits (like those carried on HMHS Britannic) alone capable of handling twelve boats.

[citation needed] She was used for transatlantic trooping from Canada and the United States in 1942. in 1943, Windsor Castle was sunk by a torpedo launched from a German aircraft while in the Mediterranean Sea as part of convoy KMF 11.