The Seraph was a standard S-class, submarine, laid down at Barrow in mid-August, 1940.
S-class submarines were comparatively small, displacing 715 tons on the surface and less than 1,000 tons submerged. Seraph was 217 feet long overall, had a breadth of 23.8 feet and a depth of 10 feet. Twin shafts driven by 1,900 b.h.p. diesels and 1,300 b.h.p. electric motors gave her speeds of 14 knots on the surface and 9 knots submerged.
As for armament, the S class carried a 3-inch gun and three machine guns plus seven 21-inch torpedo tubes. Her ship's company totaled 44.
During the early autumn she and other submarines of the 8th Flotilla reconnoitered the beaches and landing places for the Allied invasion of North Africa.
