Italy’s Leonardo da Vinci Submarine Planned to Terrorize New York Harbor
Captain Gazzana-Priaroggia’s legacy, and that of his legendary submarine, endures in the modern Italian Navy.
Italy gets a bum wrap for its poor showing in the Second World War. Benito Mussolini was the first fascist dictator to rise to power and global prominence, predating Adolf Hitler by more than a decade and influencing his own rise to power. Still, by 1941, Hitler’s Germany was very much the “senior” fascist in the Axis Powers, having far outstripped its southern cousin in the public imagination.
What some might find surprising is that if people had taken bets on which of the European Axis Powers was the most capable militarily at the onset of the war, the odds-on favorite would have been Mussolini’s Italy.
The Italians had several advantages over the Germans that, owing to circumstance, Rome never fully benefited from. For instance, Italy had several major armaments manufacturers and innovative aerospace firms that led to the creation of some of the most dynamic weapons and platforms of the conflict.
Italy dominated one service in particular. At the organizational level, Italy’s Regia Marina—their navy—was the most powerful, best trained, and equipped element of the Italian Armed Forces when WWII commenced. The Regia Marina had cutting-edge destroyers, cruisers, and a capable submarine force—most notably including the Marconi-class submarines.
About Italy’s Leonardo da Vinci Submarine
And one of those submarines, the Leonardo da Vinci, stands out as a truly exceptional weapons system for Italy in the war. This submarine holds the record as the most successful non-German submarine of the Atlantic Theater of the war, sinking 17 ships totaling 120,243 gross register tons (GRT)—outscoring many other Allied and Axis submarines, including notable American and British vessels.
Italy’s leading submarine ace, the dynamic Lieutenant Gianfranco Gazzana-Priaroggia, led the legendary da Vinci into battle. He, like his submarine, embodied the Regia Marina’s desire to project power well beyond the confines of the Mediterranean Sea.
Constructed as one of six Marconi-class submarines at Italy’s CRDA shipyard in Monfalcone, near Trieste, in the late 1930s, the Leonardo da Vinci was launched in September 1939, only days after the beginning of the war. This lethal sub was designed as an oceangoing vessel, capable of operating in both the Mediterranean as well as the Atlantic.
She carried a crew of 57 and was equipped with eight 21-inch torpedo tubes, a 100mm deck gun, and four 13.2mm anti-aircraft guns. Its top speed was 17.8 knots (around 20 miles per hour) on the surface and 8.2 knots (around 9.5 mph) submerged, with a range of about 3,000 miles—making her Italy’s most formidable long-range weapon.
When compared to the more advanced German Kriegsmarine U-Boats, however, the Leonardo da Vinci and her five other Marconi-class sister submarines were smaller and had slower emergency dive times. This posed tactical challenges, particularly when evading Allied anti-submarine warfare systems.
Compared to other Italian submarines, though, the Marconi-class submarines were a definite upgrade. These subs balanced maneuverability for operations in the Mediterranean with the endurance needed for missions in the Atlantic Ocean.
Italian submarine warfare tactics differed from the more successful German U-Boat “Wolf Pack” tactics in that Italian subs emphasized submerged attacks, followed by finishing off targets with surface machine gunfire. These differences limited joint operations with the Kriegsmarine, but the Leonardo da Vinci seamlessly adapted to its independent role.
The Da Vinci’s Impressive Service Record
With Italy’s entry into WWII in June 1940, the Leonardo da Vinci was dispatched from Naples to the BETASOM base in Bordeaux, occupied France, to join the Italian Atlantic submarine flotilla. In order to do so, it snuck through the Allied gauntlet along the Strait of Gibraltar, still controlled by the Royal Navy from its coastal naval base there.
The submarine conducted 11 war patrols between 1940 to 1943, operating primarily in the Atlantic, with later missions extending to the Indian Ocean. Its early patrols from December 1940 were largely unsuccessful, reflecting the technical and tactical challenges faced by Italian submarines in the harsh Atlantic environment.
By 1941, however, the Leonard da Vinci began demonstrating its lethality, sinking its first ship, the Shell oil tanker Auris on June 28. By 1942, young submarine ace Gianfranco Gazzana-Priaroggia was placed in command. His aggressive tactics and strategic acumen transformed the Leonardo da Vinci into a terror of Allied shipping.
During Operation Neuland in February 1942, for example, the sub sank a Brazilian and a Latvian freighter off Brazil, totaling 7,201 GRT. Later in June of that year, it sank four vessels—a Panamanian schooner, a Danish freighter, a Dutch freighter, and a British collier—for a combined 19,997 GRT.
Da Vinci’s most notable and tragic sinking occurred on March 14, 1943, when it torpedoed the 21,516-ton troopship RMS Empress of Canada in the South Atlantic, 400 miles west of Africa. That Allied ship had been nicknamed “The Phantom” for its ability to evade German U-Boats. Lieutenant Gazzana-Priaroggia allowed the skipper of the doomed Empress of Canada 30 minutes to abandon ship before firing his second torpedo that sank the Allied ship in 20 minutes.
The sinking of the RMS Empress of Canada accounted for nearly a fifth of the Leonardo da Vinci’s total tonnage sank. By 1943, Italy’s naval command recognized Gazzana-Priaroggia’s leadership and promoted him to Capitano di Corvetta.
Italy Planned an Audacious Attack on New York Harbor
This submarine was also at the forefront of revolution in Italian special operations naval warfare. In July 1942, Leonardo da Vinci was selected for a most daring special operation intended to attack New York Harbor. This was a plan concocted by the devious mind of Junio Valerio Borghese, a pioneer of Italian naval special forces.
The submarine was modified to carry a CA-class midget submarine and 28 explosive charges, to be deployed by divers who would infiltrate the harbor and attach mines to Allied ships. The operation aimed to demoralize the Americans and force the US Navy to divert greater resources to coastal defense.
During the autumn of 1942, da Vinci conducted trials for the mission with the CA-class craft, but delays due to technical modifications postponed the mission. The submarine returned to its Atlantic patrols, and the New York attack was inevitably scrapped. This episode, though, highlighted Rome’s innovative approach to asymmetrical warfare, building on prior successes with ‘human torpedoes’ at Gibraltar and Alexandria.
The Da Vinci’s Terrible End
The Leonardo da Vinci’s winning streak was bound to run out sooner or later. On May 22, 1943, after completing its Indian Ocean mission, the sub signaled its intention to return to Bordeaux. This transmission was a fatal error, as Allied direction-finding equipment pinpointed the submarine’s location.
Three-hundred miles west of Vigo, Spain, the destroyer HMS Active and the frigate HMS Ness,escorts to convoys WS-30 and KMF-15, subjected the submarine to intense depth charge attacks. Those attacks proved successful. Leonardo da Vinci was sank off the coast of Spain, where she was lost with all hands—including her iconoclastic skipper, Gazzana-Priaroggia.
The loss of this submarine was a serious blow to Italy’s Regia Marina. Gazzana-Priaroggia was posthumously awarded Germany’s Knight’s Iron Cross and Italy’s Gold Medal for Military Valor by King Vittorio Emanuele III himself.
Captain Gazzana-Priaroggia’s legacy, and that of his legendary submarine, endures in the modern Italian Navy. In fact, two modern Sauro-class submarines named S520 Leonardo da Vinci (commissioned in 1981) and S525 Giafranco Gazzana-Priaroggia (commissioned in 1993) served with honor in Italy’s postwar naval service.
About the Author: Brandon J. Weichert
Brandon J. Weichert, a Senior National Security Editor at The National Interest as well as a contributor at Popular Mechanics, who consults regularly with various government institutions and private organizations on geopolitical issues. Weichert’s writings have appeared in multiple publications, including the Washington Times, National Review, The American Spectator, MSN, the Asia Times, and countless others. His books include Winning Space: How America Remains a Superpower, Biohacked: China’s Race to Control Life, and The Shadow War: Iran’s Quest for Supremacy. His newest book, A Disaster of Our Own Making: How the West Lost Ukraine is available for purchase wherever books are sold. He can be followed via Twitter @WeTheBrandon.
Image: Wikimedia Commons.
