Royal Italian Navy Submarines of WW2 - Ammiragli Saint Bon

The submarine SAINT BON, as it was more simply called, was one of the four boats of the “Ammiragli” (Admirals) class, named after famous personalities of the Italian Navy: Saint Bon, Millo, Caracciolo, and Cagni. Of the four boats, only the last one would survive the war.

Designed for the “guerre de course” in far away oceans, these boats offered very high performances in range, weaponry, and dependability, performances today still exceptional for the diesel type submarine. This class was certainly the best built up to that time, and the fact that war needs force their use as transport submarines was a real squander.

The SAINT BON was built by the C.R.D.A. shipyard of Monfalcone, near Gorizia and was laid down on September 16th, 1939. Launched on June 6th, 1940, it was officially delivered on March 1st, 1941, but it remained at the shipyard for alterations, including the replacement of the cunning tower, too visible (as early war experience had demonstrated), with a smaller one of the type called “German”. It effectively did not enter service until June 12th, 1941.

Operational Life

After a brief period of training, the SAINT BON, under the command of Lieutenant Commander Gustavo Miniero, was employed, as the other boats of the same class, in transport missions to North Africa where ammunitions and fuel were desperately needed. For these missions, the four submarines were fitted for the stowage of small fuel canisters.

The first mission called for the transport of 153 tons of gasoline to Bardia (Libya). Having left Taranto the night of the 10th of October, the night of the 12th at about 100 miles from Bardia and on the surface, the boat was attacked by an airplane, which was repulsed (and perhaps hit) by the sub’s weapons. After having disembarked the load and left for Taranto, on the 14th, the SAINT BON was again attacked at about 75 miles from Crete with another drop of bombs. Fortunately, this was also avoided. Between the 16 of November and the 21st of December, the boat completed other missions to Bardia, Derna and Benghazi.

During its last mission, the boat left Taranto on January 1942 with destination Tripoli with route north of Sicily and a load of over 155 tons of gasoline and ammunitions. The morning of the 5th, at 5:42, the SAINT BON was hit off Point Milazzo by one of the torpedoes launched by the British submarine UPHOLDER; one of the most active in the Mediterranean. The torpedo hit midship on the starboard side and caused the gasoline to explode. The boat sank rapidly taking along the whole crew but three men: Sub Lieutenant Luigi Cuomo, Sergeant Valentino Ceccon and Chief Torpedoman Ernesto Fiore, later picked up by the British submarine.

During its brief operational life, the SAINT BON completed five missions transporting a total of 700 tons of materiel.

 The SAINT BON on May 3rd, 1941.

The SAINT BON on the construction slip.