After a regular shakedown period, the submarine Leonardo Da Vinci, under the command of C.C. Ferdinando Calda, left Naples on September 22nd 1940 for newly established submarine base of Bordeaux. After the crossing of the Strait of Gibraltar, which took place on the 27th - a few days before the new moon of September 30th - the boat was sighted by two British destroyers, forcing a crash dive.
On October 2nd, after having reached the Atlantic Ocean, the Da Vinci attacked an armed ship (auxiliary cruiser) of notable dimensions (the name is unknown). While on the surface, the Da Vinci found itself in the proximity of the old aircraft carrier Argus and, under artillery attack, dived very quickly. October 8th saw another fruitless attack; this time against an armed ship, possibly a passenger liner. From the 16th to the 21st of October, the Da Vinci remained north of the Azores Islands where it conducted two chases which failed due to the superior speed of the enemy. Later, the boat moved to the area just off Lisbon from the 21st to the 27th of October. Finally, on October 31st, the boat reached BETASOM. The Da Vinci was one of the twelve boats that would reach Bordeaux during the month of October (Emo, Tarantini, Torelli, Faà di Bruno, Otaria, Baracca, Giuliani, Glauco, Calvi, Tazzoli, Argo).
After less than two months of waiting at the base, the Da Vinci departed for her second Atlantic mission on December 21st, 1940. A week later, on the 28th, it was already off the Irish coast. On the 30th, Captain Calda received a signal with the position of a British convoy, but due to a navigational error, he failed to intercept it. Here the boat continued her patrol without intercepting any enemy shipping. On the 16th, while en route for the base, it attacked without success an identified enemy destroyer. On the evening of January 20th, the submarine reentered the submarine base in Bordeaux.
The Da Vinci would leave again from the Aquitaine 's base on March 26th, but two days later it had to abandon mission because of a failure to one of the ball bearings of the primary electric motor. In a few days the breakdown was mended and the Da Vinci went back to sea on April 4th. From the 11th to the 27th of the same month, the boat remained in an area west of Ireland but, due to lack of enemy shipping, it abandoned the ineffective mission to reenter BETASOM on May 4th.
On June 18th, the Da Vinci left Bordeaux for a mission west of the Strait of Gibraltar. On the 24th, it detected an aircraft carrier escorted by destroyers but did not succeed in reaching an acceptable position of attack due to the reaction of the escort. Four days later, on June 28th, it found and sank the British oil-tanker AURIS of 8.030 t. striking the ship with four of the eight launched torpedoes. This oil tanker of Italian construction (Cantieri Riuniti dell'Adriatico) had been built in 1935 for the oil company Shell. The position of the sinking is given at 34°27'N 11°57'W from British sources and 34°28'N, 11°59'W from Italian sources. There were 32 casualties, and 27 survivors. On July 18, having reached the limit of its range, the Da Vinci left the area and returned to Bordeaux.
On August 15th, the Da Vinci was again at sea for a hunting mission off the Azores Islands. On the 19th, at 11.57 o'clock, the boat was attacked in position 35°17'N, 10°37'W by an airplane type Consolidated Catalina. In the same area, the crew made various sightings, but failed to make contact with the enemy shipping due to the prompt action of the escort units, which did not cause any damage. On September 24th, the boat was again returning to base where it would remain in the shipyard until the end of October for refurbishing. During this pause, C.C. Caldo was replaced by C.C. Luigi Longanesi Cattani. The just concluded action against convoy HG.73 had been organized in collaboration with B.d.U, and Donitz complimented the Italian allies for the collaboration provided.
At the end of the repair work, and after some testing, on November 19th the Da Vinci left again for a new mission, this time south of the Azores islands. The departure, as it would happen various times, did not take place from Bordeaux but from the auxiliary base at La Pallice, near La Rochelle. On December 2nd, the commander was forced to abort the mission because of serious damage to the horizontal rudders, and the boat reentered Bordeaux on December 2nd.
After some alteration to increase its range, the Da Vinci left again on the 28th of January 1942; this time it would be for the first mission along the Brazilian coasts, which would be reached after a navigation of one month. After these structural alterations, the buoyancy of the boat had been reduced to only 10%. After reaching the pre-assigned area just off the Antilles, the crew ascertained the absence of enemy shipping and moved closer to the New York - Brazil trade route.
On February 25th, the Da Vinci sank the Brazilian SS CADEBELO of 3.557 t. which had left Philadelphia on the 14th, and which was followed on the 27th of the same month by the Latvian SS EVERASMA of 3.644 t. The "Cadebello" was an old ship (1917) of German construction and belonging to the "Companhia de Navegacao Lloyd Brasilero"; there were no survivors. The position of this sinking is approximately given at 16°N 49°W. The "Everasma" belonged to the "Francis Grauds Company" and had been built by the British shipyard Duncans in 1920. The position of the second sinking is approximately given at 17°N 48°W. This ship was part of convoy TAW12 and there were 15 survivors. The 11th of March, the Da Vinci left the sector to reenter Bordeaux.
On May 9th, the Da Vinci was once again on a mission; this time between Porto Natal and Bahia. On June 2nd, near the Liberian coast, just off Cape Las Palmas, it sank with torpedoes the Panamanian schooner REINE MARIE STEWART of 1.087 t. The position of this sinking is given at 7°16'N, 13°20'W and there is no information regarding the sunken boat or possible survivors.
On the 7th, the Da Vinci intercepted and sank the Danish M/v CHILE of 6.956 t., in service to the British, and on the 10th the Dutch M/n ALIOTH of 5.483 t. The "Chile" was built by the Burmeister & Wain's Maskin of Copenhagen in 1915 and belonged to the shipping company "Ostasiatiske Compagni". Five crewmembers perished and the remaining 39 were rescued. The "Alioth", a ship of recent construction (1937), belonged to "Van Nievelt, Goudriaan & Co's" and was built by the shipyard Deusche Werft AG of Hamburg. Eight crewmembers were rescued, while the remaining 28 perished. The position of this sinking is given at 0.08°N, 18°52W by British sources and 4°17'N, 13°17W by the Italian authorities; a notable difference.
The series of successes continued on the 13th with the sinking of the English SS CLAN MACQUARRIE of 6.471 t. in position 5°35'N, 25°45'W (5°30'N, 23°30'W according to British fonts). Only one crewmember was lost, while the remaining 89 were rescued. This collier, built in 1913, belonged to the shipping company "Clan Line Steamers Ltd" of Liverpool. On the 20th, the Da Vinci rendezvoused with the Tazzoli to which it transferred 11 t. of diesel fuel (which the Tazzoli, in turn, transferred to the Morosini), and then returned to the base arriving on July 1, 1942 to celebrate a loot of around 20.000 t.
During the summer period, the Da Vinci was at the shipyard for structural change to allow for the installation of a pocket submarine lodged on the forward bridge. About this mission, Commander Borghese wrote: "After a year of tests and experiments conducted on the Lake of Iseo by Sub-Lieutenant Massano, in some of which I had myself taken part, the midget assault submarine 'CA' had been adapted to her new functions and was ready for action. Simultaneously, at Bordeaux, where in the meantime command of the base of our Atlantic submarines had been assumed by Captain Enzo Grossi, the possibilities I had formerly tested of using an ocean-going submarine for transporting the 'CA' to an enemy base had been realized. Two missions were in preparation with this craft, one being an attack on New York, taking the 'CA' up the Hudson into the very heart of the city; the psychological effect on the Americans, who had not yet undergone any war offensive on their own soil, would in our opinion far outweigh the material damage which might be inflicted (and ours was the only practicable plan, so far as I am aware, ever made to carry the war into the United States). The other operation provided for an attack against the important British stronghold of Freetown (Sierra Leone) where the British South Atlantic Squadron was stationed. The undoubted difficulties that such operations of very wide range involved were to a large extent neutralized by the factor of complete surprise; the appearance of assault craft of the Italian Navy, which had so far limited their efforts to the Mediterranean area, would certainly not be foreseen: defensive measures against so unexpected a type of attack were presumably not in being. The action against New York was in an advanced stage of preparation and had been fixed to take place in December."
On August 10th, C.C. Longanesi Cattani left the command of the submarine to T.V. Gianfranco Gazzana Priaroggia which would contribute enormously to the fame of this boat.
On October 7th, the Da Vinci left Le Verdon for another mission. Between the 25th and 30th, it conducted patrol off Capo Verde, but having failed to locate any traffic it moved off Cape San Rocco. On November 2nd, it sank the British SS EMPIRE ZEAL of 7.009 t. On the 3rd, it fired 5 torpedoes against the Dutch SS Frans Hals missing the target, and receiving some damage from the fire returned by the merchant ship. On the 5th, it sank the Greek SS ANDREAS of 6.566 t. in position 2°00'S, 30°30'W, follow the on the 10th by the American Liberty ship SS MARCUS WHITMAN of 7.176 t. in position 5°44'S, 32°41'W (5°40'S, 32°41'W according to British fonts). The Andreas was an old ship built in 1919 by Harland & Wolff in Belfast, Ireland, and it belonged to the Greek company "Ionian Steamship Co Ltd". Previously she had been known as the Philadelphia in 1919 and the New Mexico in 1933. The Liberty ship was steaming from Capetown to Dutch Guiana without a load. The 41 members of the crew and the 11 militiamen of the "Naval Armed Guard" survived, eventually reaching the Brazilian coasts in four lances, one of which was motorized.
This series of successes continued on the 11th with the sinking (with the cannon, the Da Vinci had exhausted all torpedoes) of the Dutch SS VEERHAVEN of 5.291 t. in position 3°51S, 29°22W. This ship was built in 1930 by NV Scheepvaart Maatschappij Noorze, and all 45 crewmembers were eventually rescued. Again, on the 28th, it rendezvoused with the Tazzoli to which it surrendered 30 t. of diesel fuel, to then reenter Bordeaux after 60 days of navigation and the sinking of 4 ships for a total of 26.042 t.
On February 9th 1943, the boat was again at sea, but it had to abort mission because of a breakdown. A few days later, on the 20th, it was again at sea. The Da Vinci, still under the command of Priaroggia, but with a new Chief Engineer (C.G.N. Giuseppe Battisti disembarked and C.G.N. Battaglini replaced him) started a long mission in the South Atlantic and the Indian Ocean. This mission would be conducted in collaboration with the Finzi, a boat under the command of T.V. Mario Rossetto.
On March 14th, the Da Vinci sunk with two torpedoes the British transatlantic EMPRESS OF CANADA of 21.517 t. This is a sad episode since along with 3000 British soldiers there were 500 Italian prisoners of war . The submarine succeeded only in recovering S.T. physician Vittorio Del Vecchio. The position of the sinking is given at 1°13'S, 9°57'W. This elegant transatlantic was built by the shipyards Fairfield in Glasgow in 1922, and it belonged to the Canadian Pacific Railway Co.
On the 18th, the LULWORTH HILL of 7.628 t., ship previously signaled by the Finzi, was sunk with the torpedo while the Da Vinci was submerged in position 11°00'S, 0°35'E (10°10'S-1°00'E according to the British authorities). The "Lulworth Hill" was built in 1941 by Dorset Steamship Co Ltd. The Finzi eventually transferred to the Da Vinci 9 t. of diesel fuel, 6 t. of lubricants, 10 t. of water, three 450mm torpedoes, and provisions in order to continue the mission in the Indian Ocean. Additionally, the Da Vinci transferred to the Finzi the Italian lieutenant rescued at sea and the prisoner of war (sailor gunner) James Leslie Hull.
The Da Vinci, by now in the Indian Ocean, continued hunting off the port of Durban, in South Africa. On April 17th, it sank the Dutch SS SEMBILAN of 6.566 t. in position 31°30'S, 33°30'E, followed on the 18th by the British MANAAR of 8.007 t. in position 30°59'S, 33°00'E and on the 21st by the Liberty ship JOHN DRAYTON of 7.177 t. in position 32°03'S, 34°04'E. The John Drayton was a typical Liberty launched in 1942 from a shipyard in North Carolina.
On the 25th the victim is the DORYESSA, a British oil-tanker of 8.078 t. and last victim of the series. The "Doryessa" belonged to the oil company Shell and had been built in 1938 by the shipyard Lesile. Eleven crewmembers were saved, while the remaining 53 perished. The sinking was given in position 32°03'S, 34°04'E, very close to the one of the John Drayton. On May 6th, T.V. Gazzana Priaroggia was promoted "for service in war" to the rank of C.C. and few days later, on May 22nd, the Da Vinci launched the last radio signal informing the base that the following day it would begin "hidden" navigation. The boat was expected to arrive in Bordeaux within a week, but it would never arrive. In 1945, the English Admiralty confirmed that on May 23rd 1943 at 11.35 (T.M.G.) the destroyer "Active" and the frigate "Ness " conducted an attack just off Cape Finestrelle. There were no survivors. (The two units were part of the escort for convoy WS-30 and KMF-15.)
The Leonardo Da Vinci arriving in Bordeaux.
The Leonardo Da Vinci returning to Bordeaux after its first patrol.
Men from the S. Marco regiment are presenting arms.
The Leonardo Da Vinci returning to Bordeaux after its seventh patrol.