Try this as one of your first submarine models. Germany started to develop the large, long range submarine U-IX series in 1935-36. The type IX had 5 external torpedo containers (3 at the stern and 2 at the bow) which stored 10 additional torpedoes. As mine layers, they could carry 44 TMA or 66 TMB mines. Secondary armament was provided by one large Utof 105/45 gun with about 110 rounds plus one 3.7cm and one 2cm Flak gun.