The negative development of the conflict and the immediate necessity to halt the Allied forces forced the Submarine Command to deploy the TRITONE for operational duties even before the crew and boat were ready. Thus, under the command of Lieutenant Commander Paolo Monechi, the boat left Cagliari on January 18th, 1943 for its first and last patrol. The boat was instructed to reach the area off Bougie where there was intense enemy traffic.
On the 19th in the afternoon, convoy MKS6 was in position 37°06N, 05°22’E course 250 moving at a speed of 7 knots when H.M.C.S. Port Arthur, one of the escort units, picked up a faint asdic (sonar) contact at a range of 1400 yards, bearing 165. It was the TRITONE which was lying in wait for the convoy to pass by. At that point, aboard the Canadian ship Sub-Lieutenant P.R. Cowan took charge of the asdic and at a range of 1200 yards speed was increased to 12 knots. After the initial hesitation, the target was positively identified as a submarine and the Flower Class corvette went on the chase. After the launch of the first few charges, the nearby explosions caused the corvette to lose the use of some instrumentation, including asdic, thus a signal was sent to H.M.S. Antelope, another of the escort units, to close position. Unbeknown to Captain E.T. Simmons, the commanding officer of the Port Arthur, the TRITONE had already been mortally wounded.
The chase went on and at 14:23 the crew of the Port Arthur saw the submarine break the surface down by the stern with crew members jumping out of the cunning tower and into the water port side. Although the situation of the Italian boat appeared desperate, H.M.S. Antelope (Lieutenant Sinclair) opened fire with a 4.7” gun, hitting the hull of the TRITONE many times and causing great devastation. Two minutes later, the boat sank by the stern. After the attack, Antelope proceeded to rescue the survivors, amongst them the commanding officer, three officers, and twenty-two ratings, one of whom was injured in the leg from shrapnel.
Later reports indicated that the TRITONE had been badly damaged by a depth charge launched by the Port Arthur and that the Italian captain had opted to take the boat to the surface. Once the maneuver was completed, orders were immediately given to scuttle. Despite the cannon hits to the cunning tower and the hull, the submarine’s fate had already been decided. Still, the close range attack caused many casualties. The hull of the TRINTONE still containing part of the crew sank to the deep bottom of the sea where it still rests. Amongst the victims there was Mr. Bove, a civilian worker who was finishing some of the warranty work aboard the unlucky vessel.
Finishing touches on the TRITONE at the Monfalcone Shipyard near La Spezia.
H.M.C.S. Port Arthur.
The last moments of the TRITONE.