Saga of the Submarine Leonardo da Vinci

At the beginning of World War II the Italian Regia Marina had the largest submarine fleet, by tonnage, in the world. Today, of course, the Italian contribution tends to be overshadowed by that of the German submarine campaign with Germany building many more boats during the war than any other power and being by far the most successful with them. The Italian submarines, however, did a great deal of damage to Allied shipping and operated in areas as far flung as the north and south Atlantic, the Mediterranean, the Red Sea and even in the Pacific. Of all the famous named associated with the Italian underwater war effort none are as famous as that of the submarine Leonardo da Vinci, the most successful Italian submarine of the war, and her most famous commander Gianfranco Gazzana-Priaroggia who was the most successful non-German submarine captain of the entire war. The story of the Leonardo da Vinci is one of the most exciting in the history of submarine warfare and it fully deserves its status as the most famous Italian submarine of all time and one of the most famous boats of any country.

The Leonardo da Vinci was one of six Marconi-class submarines built at Monfalcone in 1938 and 1939. The Marconi-class were fairly large boats, 251ft long with 1,510 tons submerged displacement and a crew of 57 men. Armed with four bow and four stern torpedo tubes, one 3.9in deck gun and four 13.2mm machine guns (mainly for anti-aircraft defense) they had a range of nearly 3,000 miles, a top surface speed of just over 17 knots and so were formidable weapons capable of operating far from home. Of course, their size also came with drawbacks particularly in being slow to submerge. However, all of the Marconi-class proved successful boats and the Leonardo da Vinci was the most successful of all. She was launched in 1939 and when the Kingdom of Italy entered World War II in 1940 the Leonardo da Vinci, commanded by C.C. Ferdinando Calda, was ordered from her home port of Naples to Bordeaux in German-occupied France where the Italian submarine base for operations in the Atlantic was being established, BETASOM. Slipping past the British fortress at Gibraltar was always problematic and the submarine was spotted by two British destroyers but managed to crash dive and elude them.

On the way to Bordeaux the Leonardo da Vinci made several attacks on enemy vessels but none succeeded. One hunt was spoiled by attacking planes from a nearby British aircraft carrier, other targets were able to outrun the submarine and so on. However, the boat arrived finally at Bordeaux and after less than two months was dispatched again into the north Atlantic in December of 1940. Once again, the results were disappointing. A signal came in from HQ to join in an attack on a British convoy while off the coast of Ireland. Captain Calda quickly raced to join the attack but, due to a navigational error, their position was off and no target was to be found. No other targets were sighted during the patrol and on the way back Captain Calda launched an audacious attack on a British destroyer (vessels submarines generally try to avoid) but neither side got any joy. The destroyer and submarine escaped unscathed and Leonardo da Vinci returned to port. The first patrols of 1941 likewise proved frustrating. The first had to be abandoned because of a mechanical problem with one of the boat’s electric motors and the second, again off the Irish coast, ended with no enemy ships being sighted.

This, however, was fairly typical as the life of a submariner is mainly characterized by long periods of boring inactivity followed by the sudden explosion of mind-shattering danger. In June of 1941 the Leonardo da Vinci took up a new hunting ground in the very dangerous waters west of Gibraltar. Soon enough a British aircraft carrier was spotted but the efforts of her destroyer escorts prevented the Leonardo da Vinci from being able to make an attack. Finally, however, a victory was achieved toward the end of the month when a large oil tanker was attacked and sunk with four torpedo hits. At 8,030 tons this ship, the Auris, was quite a first prize indeed. In August the submarine was spotted and attacked by a Catalina flying boat. The Leonardo da Vinci survived and because Italian submarines tended to slow to dive necessity made them highly proficient anti-aircraft gunners and many Allied planes that attacked Italian submarines found them much more deadly prey than others. Later, other targets were sighted but powerful escorts always prevented an attack and the sub had to return to port with no victories for a lengthy period of refit and repairs.

While in port, the Leonardo da Vinci received a new commanding officer when Captain Caldo was replaced by C.C. Luigi Longanesi Cattani. When the boat finally put to sea again to hunt in the waters off the Azores there was, again, no successes and the sub had to return to port due to a rudder malfunction. As 1942 dawned the Leonardo da Vinci was dispatched to a new and distant hunting ground, off the Brazilian coast. It would take time to get there but the shipping route from New York City to Brazil was expected to be ripe with targets and less heavily defended than the north Atlantic shipping lanes. This time, such expectations were met and in February of 1942 the submarine scored two solid successes with the sinking of a Brazilian and a Latvian freighter for a combined total of 7,201 tons. After returning to home base, the Leonardo da Vinci was back in action off the Brazilian coast again in June and met with even greater success, sinking a Panamanian schooner, a Danish freighter, a Dutch freighter and a British collier for a combined total of 19,997 tons. The Italian submarine returned to port covered in glory and to receive some special modifications for a top secret assignment.

By 1942 the Kingdom of Italy was also at war with the United States and at the outset Mussolini asked for proposals on how to take the war to the Americans. One idea showed promise. During the war Italy had scored several astounding successes with the use of human-guided torpedoes. These were attached to the hull of a submarine which would approach an enemy port. Men in diving gear would then ride these “torpedoes” piggyback (hence their nickname of ‘pigs’) into the enemy harbor and, from underwater, attach mines to the hulls of enemy ships, sinking them when detonated. Italy had successfully carried out such daring attacks on heavily defended British ports such as Gibraltar and Alexandria, Egypt during the war. In 1942 it was decided to try such an attack on the vital American port of New York City. The damage from such an attack would not be too materially significant but it would have a devastating impact on morale for the United States and force the American military to inordinately redeploy forces to defend against another such attack that, in all likelihood, would never come. The operation was authorized and Leonardo da Vinci was modified to carry the special mini-subs to be taken to America’s largest city.

In August of 1942, the Leonardo da Vinci received a new commanding officer, one who would be its most famous; T.V. Gianfranco Gazzana Priaroggia. Born in Milan in 1912 of Genoese ancestry, Gazzana-Priaroggia had been executive officer under one of the greatest submarine commanders; Carlo Fecia di Cossato, and he would pay his old superior the highest complement by surpassing his record. Meanwhile, the Leonardo da Vinci was refitted and put through a number of tests for the attack on New York before her commander finally informed the high command that she was ready to undertake the mission. However, to his dismay, the high command replied that the mission would be postponed for at least a year. No one then knew why but evidence indicates that Mussolini was counting on an even more powerful weapon to be ready by that time: an atomic bomb. Of course, that never came about and so the submarine had its deck gun restored but left the fittings for the attachment of the mini-subs in place so that it would be ready to undertake the attack on New York at a later time. That mission, however, was to remain unfulfilled and is rarely ever remembered today. Still, there was plenty more for Leonardo da Vinci to do in the Battle of the Atlantic with her new captain at the helm.

Again, the initial patrol off Cape Verde was disappointing with no targets being sighted. The next, however, off Cape San Rocco, was a crushing success. In November, in quick succession the submarine torpedoed and sank a British freighter, a Greek freighter, an American ‘liberty ship’ and a Dutch freighter for a combined total of 26,042 tons of enemy shipping sent to the bottom. The Leonardo da Vinci had been so successful in fact that the Dutch freighter had to be sunk with the deck gun because the submarine had fired all of its torpedoes. The boat and crew returned to port to a hero’s welcome. When they put to sea again it would be 1943 and an initial cruise had to be aborted because of mechanical problems but once these were addressed they were soon back in action with orders to prey on Allied shipping from the South Atlantic to Indian Oceans. In March of 1943 they had their first success of the new year when they torpedoed the Canadian troopship the RMS Empress of Canada. This was by far the biggest target that the Leonardo da Vinci or her captain had ever sunk at 21,517 tons. However, it was a bitter-sweet victory as among the many Allied troops killed in the sinking were about 500 Italian prisoners-of-war. Only one Italian prisoner was able to be rescued so that, despite an enormous victory, no one on the submarine felt very cheerful.

Still, the war went on and a few days later the Leonardo da Vinci sank another British freighter before moving into the waters of the Indian Ocean. There, in April, the submarine sank a Dutch freighter, a British freighter, another American ‘liberty ship’ and a British tanker for a total of 29,828 tons. It was another resoundingly successful campaign for Italy’s most famous submarine. Sadly, those victories in a far distant sea were to be the last for Captain Gazzana-Priaroggia and the Leonardo da Vinci. On their way back to port the submarine was spotted and attacked by two British warships; the destroyer HMS Active and the frigate HMS Ness west of Cape Finisterre, Spain. The Leonardo da Vinci submerged, going deeper and deeper, trying to evade and elude the enemy but it was ultimately to no avail. Subject to fierce depth charge attack, the boat was finally destroyed and lost with all hands. Captain Gianfranco Gazzana-Priaroggia was posthumously awarded the Gold Medal for Military Valor by the Kingdom of Italy and the Knight’s Iron Cross by Germany in recognition of his great achievements.

With that sad day of May 23, 1943 the saga of the Leonardo da Vinci came to a tragic end. Yet, it had established itself as one of the most successful submarines in naval history. During its wartime career, spanning from June 1941 to May 1943 the Leonardo da Vinci had sunk 17 Allied ships for a total of 112,615 tons of enemy shipping destroyed, more than any other non-German submarine of the entire war. The story of this remarkable submarine is one that all Italians can look back on with pride and respect.