Scale: 1:48. Plan showing the port inboard profile from the starboard side, a plan of the bridge, the superstructure plan, a plan at the greatest breadth, a plan of the flat at frames 98-107, a plan below the main flats at frames 41-75, and sections through frames 83, 117, 67, 32, 102, 94, 49, 24 and 10, as fitted for the two S class submarines Sturdy (1943) and Stygian (1943). The plan includes alterations in red ink for Stygian.