The Ambra was a costal submarine of the Type 600, class Perla, “600” series, type Bernardis, and entered service August 4th, 1936. At the beginning of the war, the Ambra operated both in the Gulf of Taranto and in the waters off Alexandria in Egypt. In the early hours of December 16th, 1940, it was spotted by two British ships and subjected to twelve hours of anti-submarine hunting but managed to escape unharmed.
The launch of the Ambra
In March 1941, under the command of Lieutenant Mario Arillo, it was sent, along with the Ascianghi and Dagabur, to an area between Alexandria and Cape Krio (island of Rhodes). On March 31st at 2:37 AM, on her return course, she came across a large, escorted ship sailing about 2,000 meters away and at a speed of 10 knots. Moving closer, at 2.44 AM Captain Arillo launched three torpedoes, remaining on the surface even after the launch to make sure of the result: two of the torpedoes hit the unit – it was the modern British light cruiser HMS Bonaventure, which was escorting, along with three destroyers, a convoy of two transports (the Bonaventure may have been already been previously damaged by the Dagabur) which sank in position 32°20′ N and 26°35′ E.
The first torpedo struck at the aft end of the forward engine room and the second detonated abreast the aft engine room, destroying the aft watertight transverse bulkhead and exposing ‘X’ magazine to the open sea. The consequent severe flooding caused a severe list to starboard within minutes and the ship capsized within six minutes of the attack.
H.M.S. Bonaventure
Of the British crew, 138 men (23 officers and 115 non-commissioned officers and sailors) were lost, while the survivors were rescued by the destroyer H.M.S. Hereward. Ambra then submerged, evading seven depth charge attacks by the destroyer H.M.S. Stuart, which lasted for several hours. The action was one of the main successes achieved by Italian submarines against warships.
Captain Arillo
Between March and April 1942, the Ambra was converted into a submarine “carrier” of assault craft, with the application of three cylindrical container for SLCs (pigs or chariots) resistant up to a depth of 90 meters: they were placed on the deck, one forward of the turret and the other two, coupled, aft.
The cylindrical container for SLCs (pigs or chariots)
In April 1942 the Ambra was assigned to the first special mission (Operation G.A. 4): an SLC attack on the British naval base in Alexandria, Egypt. This mission was supposed to complete and further the effects of the previous raid on the port of Alexandria: the targets would have been the battleship Queen Elizabeth – which, despite the serious damage, had been refloated and brought to a floating dock – and the large submarine support ship Medway.
The Ambra departed from La Spezia on April 29th and docked in Leros on May 5th. After embarking three SLCs and 9 operators of the 10th Light Flotilla (4 officers and 5 non-commissioned officers and sailors; 6 were destined for the attack and 3 were in reserve) who had arrived by plane on May 6th. After addressing some faults that had occurred in the meantime, the submarine departed Leros on May 12th, arriving off Alexandria two days later.
Around 7 PM the Ambra moved to a depth of ten meters and only few hundred meters from shore, and at 8:50 PM released the SLCs. However, the submarine had been moved by the strong current a few miles away from the planned point, and Captain Arillo felt that he should not report it to the SLC crews as he was not sure of the actual position After all, it was not the only problem: one of the SLC pilots, Egil Chersi, felt ill and had to be replaced together with his second. After the release, one of the SLCs, malfunctioning, had to be sunk and the two operators were forced to swim to shore. The crews of the other two vessels, unable to find their targets, had to sink the SLCs and swim to shore (all 6 operators were captured, 4 immediately and the remaining two on June 29th). The Ambra, which left Egyptian waters around 9 PM, arrived in La Spezia midday on May 24th.
On December 1st, 1942, Operation N.A. 1 against the port of Algiers began. The Ambra was supposed to bring a mixed unit near the Algerian port: three SLCs with their crews (6 men) and 10 “Gamma men” (divers saboteurs) of the X MAS (the “Gammas” were composed of elements of both the Navy and the Army, 5 and 5; their commander was the lieutenant of the Naval Arms Corps Agostino Morello); the submarine would release “Gamma” and SLC while resting on the bottom of the sea, while two men from the X MAS would remain on the surface, acting as lookouts.
On December 4th, in the early afternoon, the submarine left La Spezia and three days later arrived off the Algerian coast; however, due to adverse weather and sea conditions, he had to wait until December 11th before he could approach Algiers to begin the final phase of the operation. Navigating submerged to elude the strong vigilance, and with the echo sounder broken, the submarine hit the seabed abruptly at about ninety meters. The boat kept dragging on the sandy bottom until it reached a depth of about 18 meters and then came to a rest. However, when the two lookouts were sent to the surface, it turned out that the coast was not visible, nor were any ships to be seen.
Moving again and very close to the seabed, stopping from time to time to send lookouts to the surface, the submarine finally found itself inside the bay with 6 merchant ships moored all around. Since they were already behind schedule, the raiders were sent out (first the “Gamma”, between 10.30 and 11 PM, followed by the SLC between 11 PM and 11.20 PM. However, the crews did not act with coordination: only one of the SLCs and five “Gammas” managed to carry out the attack, while the others hurried to try to return to the submarine and one surrendered to the local authorities, thus triggering the alarm. Despite the risk the Ambra remained on the bottom until 2.54 AM, before having to leave without anyone having returned; the raiders had all fallen prisoners.
During the departure there was also a collision with a wreck, fortunately without consequences; It was not until 19:45 on December 12th – after being submerged for 36 hours – that the Ambra was able to return to the surface, recharge the batteries and refresh the air supply. At noon on the 15th, the submarine docked at La Spezia. Although less than half of the raiders managed to plant explosive charges, the steamers Ocean Vanquisher (7174 GRT) and Berto (1493 GRT) were sunk, and two other large merchant ships, the Empire Centaur (7041 GRT) and the Armattan (4558 GRT) suffered serious damage. Commander Mario Arillo received the Gold Medal for Military Valour; twelve of the raiders were decorated with the Silver Medal for Military Valor and another with the War Cross for Military Valor.
The third and final mission of the Ambra took place in 1943 during the Sicilian campaign. The commander of the submarine was no longer Arillo, but Lieutenant Commander Renato Ferrini. On the night of July 17th, the submarine, carrying three MTR explosive boats, moved near Syracuse to attack the ships moored in the area. At round three o’clock it was spotted by an anti-submarine aircraft and hit with depth charges and forced to surface with serious damage. Towed to Naples by the torpedo boat Partenope, after temporary repairs, Ambra relocated to La Spezia on July 27th.
At the proclamation of the armistice – September 8th – the boat was still under repair, and it was scuttled. Salvaged by the Germans, it was sunk again in the harbor in 1944, during an aerial bombardment.
Operational Records
| Patrols (Med.) | Patrols (Other) | NM Surface | NM Sub. | Days at Sea | NM/Day | Average Speed |
|---|---|---|---|---|---|---|
| 31 | 16890 | 2747 | 162 | 121.22 | 5.05 |
Actions
| Date | Time | Captain | Area | Coordinates | Convoy | Weapon | Result | Ship | Type | Tonns | Flag |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3/31/1941 | 02.44 | T.V. Mario Arillo | Mediterranean | 33°20’N-26°35’E | Torpedo | Failed | H.M.S. Stuart | Destroyer | Great Britain | ||
| 3/31/1941 | 02.44 | T.V. Mario Arillo | Mediterranean | 33°20’N-26°35’E | Torpedo | Sank | H.M.S. Bonaventure | Light Cruiser | 5440 | Great Britain | |
| 12/12/1942 | T.V. Mario Arillo | Mediterranean | Agerie’S | Artillery | Sank | Berto | Steam Freighter | 1493 | Norwey |
Crew Members Lost
| Last Name | First Name | Rank | Italian Rank | Date |
|---|---|---|---|---|
| Fanizza | Leonardo | Naval Rating | Comune | 7/17/1943 |