1941(Helge Fischer HFWI-8a)
- Class: Cagni - 4 submarines of 1939
- Displacement: 1,708 (surface)/2,190 (submerged) tons
- Dimensions: 288 x 25 x 19 ft.
- Machinery: 2-shaft Diesels, H.P. 4,370/1,800 = 17/9 knots
- Armament: 14-17.7in T.T. (8 forward + 6 aft), 36 torpedoes; 2-3.9in, 4-13.2mm (2x2) guns
- Complement: 78
- Builder: Cantieri Riuniti dell'Adriatico, Monfalcone
- Keel Laid: 16 Sep 1939
- Launched: 20 Jul 1940
- Completed: 1 Apr 1941
- Notes: Largest class of attack submarines built for Italian Navy. Projected for commerce raiding, whence the lesser caliber of torpedoes (judged sufficient against merchant ships) and large number carried.
- Service: On completion used to transport supplies to North Africa, completing five missions. Then sent to Atlantic in Oct 1942, completing a record 137-day patrol at Bordeaux in Feb 1943. Second patrol to Cape of Good Hope interrupted by surrender, whereupon she made for Durban. Sank two merchant ships (9,395 GRT) and seriously damaged British AMC Asturias. Returned to Italy in 1944 and used to train Allied ASW forces. Discarded 1 Feb 1948. All three sisters were lost on transport missions in the Mediterranean.