Italian submarines in World War Two

Italian Commanders


Paolo Monechi

Born  28 Jan 1911Reggello Valdarno (Florence)
Died   1995(83)Florence

Ranks

  T.V.Tenente di Vascello
1 Mar 1942 C.C.Capitano di Corvetta

Decorations

Career information

GUGLIELMO MARCONI (T.V. First Officer): from 08.02.1940 to ?
ALESSANDRO MALASPINA (T.V. First Officer): ? to May 1941?
MOCENIGO (T.V. C.O.): from 01.11.1941 to 23.06.1942.
Promoted to C.C. on 01.03.1942.
ALABASTRO (C.C. C.O.): from 29.06.1942 to 14.07.1942.
TRITONE (C.C. C.O.): from 10.10.1942 to 19.01.1943 (sunk, Monecchi survived as PoW).

Commands listed for Paolo Monechi


Submarine Type Rank From
Mocenigo (MO, I.19)Ocean goingT.V.1 Nov 194123 Jun 1942
Tritone (TN)Sea goingC.C.24 Jun 194219 Jan 1943
Alabastro (AB)Coastal / Sea goingC.C.29 Jun 194214 Jul 1942

War patrols listed for Paolo Monechi

 SubmarineDateTimePortArr. dateArr. timeArr. portMilesDescription
Mocenigo (MO, I.19)2 Nov 19410810La Spezia2 Nov 19411745La Spezia68Exercises, escorted by the auxiliary Torre Annunziata.

Mocenigo (MO, I.19)7 Nov 19410745La Spezia7 Nov 19411700La Spezia61,2Exercises, escorted by MAS 570.

Mocenigo (MO, I.19)8 Nov 19410810La Spezia8 Nov 19411538La Spezia26Exercises.

Mocenigo (MO, I.19)10 Nov 19410813La Spezia10 Nov 19411500La Spezia15Exercises.

Mocenigo (MO, I.19)11 Nov 19411650La Spezia11 Nov 19411740La Spezia1Exercises.

Mocenigo (MO, I.19)12 Nov 19410917La Spezia12 Nov 19411250La Spezia6Exercises.

Mocenigo (MO, I.19)14 Nov 19410935La Spezia14 Nov 19411010La Spezia1Exercises.

Mocenigo (MO, I.19)16 Nov 19410750La Spezia16 Nov 19411435La Spezia36Exercises.

Mocenigo (MO, I.19)17 Nov 19410800La Spezia17 Nov 19411220La Spezia28Exercises.

Mocenigo (MO, I.19)18 Nov 19410800La Spezia18 Nov 19411200La Spezia29Exercises with the submarines Colonna and Acciaio, escorted by the auxiliaries Crotone, Santantioco and Capodistria.

Mocenigo (MO, I.19)20 Nov 19412210La Spezia22 Nov 19410845Naples340Passage La Spezia-Naples.

Mocenigo (MO, I.19)26 Nov 19410900Naples26 Nov 19411640Naples40Exercises.

Mocenigo (MO, I.19)29 Nov 19410925Naples29 Nov 19411645Naples45Exercises.

Mocenigo (MO, I.19)4 Dec 19411605Naples6 Dec 19410930Taranto510Passage Naples-Taranto with Veniero. They were to proceed on the surface at 12 knots via Caqe Palinuro (2345/4), Cape Suvero (0630/5), Cape Peloro (1030/5), Cape Colonne (2330/5) and point M.2 (Taranto) (0800/6).

1.Mocenigo (MO, I.19)11 Dec 19411115Taranto17 Dec 19411800BardiaSupply mission to Bardia and Benghazi (59 tons of fuel, 15 tons of food supplies) (part 1). Two attempts to enter Bardia on 15th and 16th December 1941 failed because of bad weather.
  12 Dec 19411240
1249B (e)
37° 13'N, 19° 21'E
(e) 37° 26'N, 19° 17'E
At 1240 hours, an aircraft was sighted at a distance of 3,500 metres. Mocenigo made a recognition signal but was not answered. As the aircraft appeared to be threatening, the submarine fired two rounds from her stern gun to keep it a t bay and it flew away. This was a Malta-based Maryland of 69 Squadron on a reconnaissance mission (Flying Officer Drew).

2.Mocenigo (MO, I.19)17 Dec 19412115Bardia21 Dec 19410915BenghaziSupply mission to Bardia and Benghazi (59 tons of fuel, 15 tons of food supplies) (part 2).
  18 Dec 1941111733° 28'N, 24° 42'EAt 1117 hours, Mocenigo sighted three destroyers, steering 020° at over 25 knots, from a distance of 14,000 metres but was unable to close for an attack.

3.Mocenigo (MO, I.19)21 Dec 19411857Benghazi23 Dec 19411825BardiaSupply mission to Bardia (15 tons of food supplies). Uneventful.

4.Mocenigo (MO, I.19)23 Dec 19412110Bardia27 Dec 19410820SudaReturn trip from supply mission to Bardia and Benghazi. Brought back a wounded captain, a sub lieutenant, fifteen sailors and ten PoWs.
  24 Dec 19411030
1034B (e)

(e) 33° 32'N, 24° 58'E
At 1030 hours, a bomber was sighted and Mocenigo dived immediately. The submarine had reached a depth of 40 metres when three small bombs were heard to explode near by. This was Blenheim 'P' of 203 Squadron (Pilot Officer Wintle) carrying out a "Trident" patrol and had sighted a surfaced submarine steering 240° at 8 knots. The bomber circled it twice, giving it a chance to identify itself, but the submarine began crash diving when the Blenheim was completing its second circuit, without making any recognition signal.

The aircraft made a dive attack from 1,500 feet, pulling out at 500 feet and releasing four 250lb A/S bombs in a salvo. They fell within an area of 20 yards and the gunner saw them all explode just to the port side of the U-boat which was just submerged but still visible under the water. The aircraft circled the position and, after 30 seconds, a 40 yards square patch of dark brown oil appeared . In fact, Mocenigo had escaped unscathed. The submarines HMS Thunderbolt and HMS Proteus, who were in the general area, were informed of the presence of this submarine but did not make contact.
  27 Dec 1941221635° 46'N, 23° 49'EAt 2216 hours, Mocenigo sighted a Spanish vessel which had left Suda and shortly after a submarine of the VENIERO class on opposite course.

5.Mocenigo (MO, I.19)27 Dec 19411700Suda31 Dec 19411525Taranto2592,07Return trip from supply mission to Bardia and Benghazi.
  27 Dec 1941221635° 46'N, 23° 49'EAt 2216 hours, Mocenigo sighted a Spanish vessel which had left Suda and shortly after a submarine of the VENIERO class on opposite course.
  31 Dec 1941024739° 12'N, 18° 20'EAt 0247 hours, a submarine of the CAGNI class was seen on a parallel course at a distance of 1,200 metres. It was not identified but was probably Dandolo.

Mocenigo (MO, I.19)5 Jan 19421005Taranto5 Jan 19421045Taranto0,5Docked.

Mocenigo (MO, I.19)12 Jan 19421215Taranto12 Jan 19421335Taranto0,5Left dock.

Mocenigo (MO, I.19)27 Jan 19421113Taranto27 Jan 19421740Taranto30,5Trials.

Mocenigo (MO, I.19)30 Jan 19421130Taranto30 Jan 19421150Taranto0,2Changed moorings.

Mocenigo (MO, I.19)4 Feb 19421046Taranto4 Feb 19421135Taranto4Changed moorings.

6.Mocenigo (MO, I.19)9 Feb 19421007Taranto11 Feb 19421321Taranto371Sailed for patrol within 8 miles of 33°30'N, 20°40'E, on a patrol line with Dandolo, but early return because of defects.

Mocenigo (MO, I.19)14 Feb 19421120Taranto14 Feb 19421530Taranto33,5Trials.

7.Mocenigo (MO, I.19)14 Feb 19421725Taranto27 Feb 19421405Cagliari1832,8Sailed for a patrol in area between 36°00'N and 36°20'N and 15°20'E and 15°40'E. On 21st February, her patrol was shifted to an area between 36°40' N and 37°00' N and between 15°20' E and 15°40' E (patrolled southeast of Malta and southeast of Cape Passero).
  18 Feb 1942121235° 33'N, 15° 36'EAt 1212 hours, two aircraft were sighted at 10,000 metres and Mocenigo dived. Shortly after, three explosions were heard.
  25 Feb 19420845At 0845 hours, the submarine Serpente was sighted.
  25 Feb 19422058At 2058 hours, an Italian steamer escorted by a destroyer were sighted at a distance of 5,000 metres. Recognition signals were exchanged. Marina Messina had informed Mocenigo of a possible encounter.

Mocenigo (MO, I.19)11 Mar 19420705Taranto11 Mar 19421215Taranto37,8Exercises.

Mocenigo (MO, I.19)13 Mar 19420703Taranto13 Mar 19421145Taranto31,3Exercises, escorted by MAS 503.

8.Mocenigo (MO, I.19)13 Mar 19421856Cagliari3 Apr 19421455Cagliari2878Patrolled north of Cape Falcon, in area between 36°00'N and 36°40'N and 00°40'E and 01°40'E.
  14 Mar 19422056
1955 (e)
37° 16'N, 5° 05'E
(0) 325° - Cape Carbon - 30 miles (French source).
At 1530 hours, a 5,000-ton tanker was observed zigzagging steering between 50 and 140°. The vessel appeared to leave the route assigned to French traffic. At 2056 hours, a stern torpedo (450mm) was fired from a distance of 1,500 metres. It hit the vessel on the port side. The tanker took a list before sinking very quickly. This as the Vichy French Sainte Marcelle (ex-Norwegian Vigoer, 1518 GRT, built 1935, she had been seized at Casablanca in June 1940) who had sailed from Marseilles for Tunis on 7th March. There were two men killed, and twenty-seven survivors. Following this mistake, the Pétain government stopped its adherence to the "Paris Protocols" which included the supply of trucks and other goods to Axis forces in North Africa.
  20 Mar 19421533
1440 (e)
36° 30'N, 1° 23'W
(e) 36° 33'N, 1° 26'W
At 1350 hours, Mocenigo heard distant turbine noises but the periscope revealed nothing. At 1510 hours, the periscope finally revealed a number of vessels proceeding on a 040° course at 20-22 knots. These were identified as two aircraft carriers (type EAGLE and ARGUS), a battleship, a cruiser and ten or twelve destroyers. The submarine moved to intercept and had reached a distance of 2,500 metres, when a first attack was thwarted by the sudden appearance of two destroyers. They had not been noticed earlier and forced the submarine to a depth of 15 metres, to avoid being rammed.

The aircraft carrier, identified as HMS Eagle, passed very near the submarine before action could be taken. She was now presenting her stern at a distance of 800 metres while HMS Argus and the battleship were turning to port. Monechi decided to fire a stern salvo of three torpedoes at Eagle and immediately took his submarine deep, as two destroyers had appeared to have discovered him, and were moving to the attack. He had reached a depth of 45 metres when an explosion was heard 3 minutes after firing, followed 2 minutes later by two more. The submarine reached a depth of 75 metres, but was not depth charged.

These were indeed the aircraft carriers HMS Eagle and HMS Argus, the battleship HMS Malaya, the light cruiser HMS Hermione and nine destroyers (these were the fleet destroyers HMS Laforey, HMS Duncan, HMS Active, HMS Anthony, HMS Wishart, HMS Whitehall and the escort destroyers HMS Blankney, HMS Croome and HMS Exmoor) on their way to carry out operation PICKET, phase 1. None of the torpedoes hit. HMS Eagle observed an explosion believed to be a torpedo at the end of its run.

Mocenigo (MO, I.19)5 Apr 19420930Cagliari5 Apr 19421015Cagliari0,7Changed moorings.

9.Mocenigo (MO, I.19)20 Apr 19421610Cagliari20 Apr 19421753Cagliari9,2Sailed for patrol between 37°20'N and 37°40'N and 09°20'E and 09°40'E to operate against an enemy force but quickly recalled.

10.Mocenigo (MO, I.19)29 Apr 19421155Cagliari20 May 19420832Cagliari2629,7Sailed for a patrol between 37°40'N and 38°20'N and 01°20'E and 01°40'E. On 30th April 1942, she was ordered to shift her patrol to 37°20'N and 38°00'N and between 02°00'E and 02°20'E. On 16th May, she was ordered off Cape Ténès.
  2 May 1942074037° 03'N, 0° 15'EAt 0740 hours, a German submarine was encountered and recognition signals exchanged. She was proceeding to the assistance of U-573 (KL Heinrich Heinsohn), who was reported in difficulty after an air attack in Quadrat CH 8218 or 37°15' N, 00°42' E. This was almost certainly U-74 (OL Karl Friedrich) who signalled at 1052 hours that she was in Quadrat CH 8137 (37°15' N, 00°10' E). Eventually, U-573 managed to reach Cartagena where she was interned, but U-74 was sunk later that day.
  2 May 1942143437° 00'N, 0° 08'EAt 1434 hours, the submarine sighted a destroyer at a distance of 16,000 metres.
  9 May 1942091237° 41'N, 2° 18'EAt 1434 hours, the submarine sighted from a distance of 13,000 metres a destroyer proceeding at 24 knots.
  18 May 19420826
0828 (e)
37° 05'N, 1° 03'E
(e) 37° 07'N, 1° 05'E
At 0811 hours, an enemy formation was observed through the periscope, proceeding on a 050° course at a distance of 8-9,000 metres. It was identified as HMS Eagle, HMS Argus, a cruiser and several destroyers. Mocenigo closed to 2,000 metres and attempted an attack on Eagle but could not get a suitable track angle.

At 0826 hours, Monechi gave the order to fire three stern torpedoes (533mm) at the cruiser from a distance of 1,200 metres and heard two hits after 90 seconds. Several depth charges followed. These were indeed the aircraft carriers HMS Eagle and HMS Argus, the light cruiser HMS Charybdis screened by screened by the destroyers HMS Westcott, HMS Antelope, HMS Wrestler, HMS Wishart, HMS Partridge and HMS Ithuriel carrying operation L.B. (flying off Spitfires to Malta). HMS Charybdis reported missed by two or three torpedoes (also sighted by HMS Partridge) and dropped three depth-charges. Partridge hunted the submarine dropping 24 depth charges. The submarine was badly shaken and went down to 96 metres. The damages forced her to abandon her patrol.

Mocenigo (MO, I.19)2 Jun 19420925Cagliari3 Jun 19420825Naples275,3Passage Cagliari-Naples.

Alabastro (AB)30 Jun 19420730Monfalcone30 Jun 19421210Venice60Passage Monfalcone-Venice.

Tritone (TN)30 Jun 19420930Monfalcone30 Jun 19421705PolaPassage Monfalcone-Pola.

Alabastro (AB)1 Jul 19421145Venice1 Jul 19421355Venice6Exercises.

Tritone (TN)2 Jul 19420930Pola2 Jul 19421745PolaTrials.

Tritone (TN)3 Jul 19420810Pola3 Jul 19421905PolaTrials.

Tritone (TN)4 Jul 19420830Pola4 Jul 19422120PolaTrials.

Alabastro (AB)6 Jul 19421405Venice6 Jul 19421630Venice6Exercises.

Tritone (TN)6 Jul 19420825Pola6 Jul 19422005PolaTrials.

Tritone (TN)7 Jul 19420825Pola7 Jul 19421135PolaTrials, escorted by the torpedo boat T.3.

Alabastro (AB)8 Jul 19420800Venice8 Jul 19421500Pola72Passage Venice-Pola.

Tritone (TN)8 Jul 19420915Pola8 Jul 19421455PolaTrials.

Tritone (TN)9 Jul 19420840Pola9 Jul 19421510PolaTrials.

Tritone (TN)10 Jul 19420910Pola10 Jul 19421635PolaTrials.

Alabastro (AB)11 Jul 19421440Pola11 Jul 19421700Pola8Exercises.

Alabastro (AB)12 Jul 19420750Pola12 Jul 19421950Pola8Gyrocompass tests.

Alabastro (AB)14 Jul 19420415Pola14 Jul 19421925Pola168Diving trials with the torpedo boat Pilo in 44°45.2'N, 14°34.8'E and 44°50.8'N, 14°34.2'E.

Alabastro (AB)15 Jul 19420855Pola15 Jul 19421104Pola10Trials.

Tritone (TN)15 Jul 19420930Pola15 Jul 19421500PolaTrials.

Tritone (TN)17 Jul 19420525Pola17 Jul 19421825PolaTrials.

Tritone (TN)18 Jul 19420925Pola18 Jul 19421055PolaTrials.

Tritone (TN)19 Jul 19420825Pola19 Jul 19420915PolaTrials.

Tritone (TN)21 Jul 19421120Pola21 Jul 19421855PolaTrials.

Tritone (TN)22 Jul 19421010Pola22 Jul 19421445MonfalconePassage Pola-Monfalcone.

Tritone (TN)29 Sep 1942Monfalcone29 Sep 1942MonfalconeTrials.

Tritone (TN)2 Oct 1942Monfalcone2 Oct 1942MonfalconeTrials.

Tritone (TN)5 Oct 1942Time?Monfalcone5 Oct 19421645MonfalconeTrials.

Tritone (TN)6 Oct 19420845Monfalcone6 Oct 19421750MonfalconeTrials.

Tritone (TN)7 Oct 19420845Monfalcone7 Oct 19421600MonfalconeTrials.

Tritone (TN)8 Oct 19420910Pola8 Oct 19421630PolaExercises.

Tritone (TN)10 Oct 1942Monfalcone10 Oct 1942MonfalconeEntered service.

Tritone (TN)24 Oct 19420730Monfalcone24 Oct 19421220Venice62Passage Monfalcone-Venice.

Tritone (TN)25 Oct 19420940Venice25 Oct 19421340Venice11,1Trials.

Tritone (TN)26 Oct 19420925Venice26 Oct 19421232Venice11,5Trials.

Tritone (TN)31 Oct 19420240Venice31 Oct 19420815Pola81,5Passage Venice-Pola.

Tritone (TN)4 Nov 19421346Pola4 Nov 19421637Pola3,6Exercises.

Tritone (TN)5 Nov 19420537Pola5 Nov 19421805Pola130Exercises.

Tritone (TN)7 Nov 19420746Pola7 Nov 19421740Pola9,3Exercises.

Tritone (TN)8 Nov 19420811Pola8 Nov 19421530Pola19Exercises.

Tritone (TN)13 Nov 19420602Pola13 Nov 19421625Sussa79,8Passage Pola-Sussa.

Tritone (TN)14 Nov 19420942Sussa14 Nov 19422055Pola82,5Passage Sussa-Pola.

Tritone (TN)20 Nov 19421915Pola22 Nov 19421556Taranto622,5Passage Pola-Taranto.

Tritone (TN)6 Dec 19420702Taranto6 Dec 19421535Taranto22,5Depth trials to 130 meters.

Tritone (TN)9 Dec 19422020Taranto12 Dec 19420745Naples528Passage Taranto-Naples. Uneventful.

Tritone (TN)14 Dec 19420805Naples14 Dec 19421645Castellammare di Stabia37Exercises and passage Naples-Castellammare di Stabia.

Tritone (TN)15 Dec 19420810Castellammare di Stabia15 Dec 19421645Castellammare di Stabia26Exercises.

Tritone (TN)16 Dec 19420810Castellammare di Stabia16 Dec 19421532Naples25Passage Castellammare di Stabia-Naples.

Tritone (TN)24 Dec 19420821Naples24 Dec 19421520Naples40Trials.

Tritone (TN)26 Dec 19420815Naples26 Dec 19421620Castellammare di Stabia33Exercises and passage Naples-Castellammare di Stabia.

Tritone (TN)27 Dec 19420803Castellammare di Stabia27 Dec 19421610Castellammare di Stabia27Exercises.

Tritone (TN)28 Dec 19420820Castellammare di Stabia28 Dec 19421600Castellammare di Stabia33Exercises.

Tritone (TN)29 Dec 19420817Castellammare di Stabia29 Dec 19421640Castellammare di Stabia36Exercises.

Tritone (TN)30 Dec 19420811Castellammare di Stabia30 Dec 19421615Naples33Exercises and passage Castellammare di Stabia-Naples.

Tritone (TN)2 Jan 19431030Naples2 Jan 19431230NaplesExercises.

Tritone (TN)3 Jan 19430930Naples3 Jan 19431825NaplesExercises.

Tritone (TN)4 Jan 19431200Naples5 Jan 19431545NaplesExercises.

Tritone (TN)7 Jan 19431025Naples7 Jan 19431945NaplesExercises.

Tritone (TN)9 Jan 19430925Naples9 Jan 19431100NaplesExercises.

Tritone (TN)13 Jan 19431853Naples14 Nov 19421945CagliariPassage Naples-Cagliari.

11.Tritone (TN)17 Jan 19432355Cagliari19 Jan 19431530SunkSailed on first patrol off Bougie, between 37°20'N and the Algerian coast, and between 05°20'E and 05°40'E. Sunk in 37°06'N, 05°22'E by HMS Antelope and HMCS Port Arthur(escort of convoy MKS.6, which was on course 250°, 7 knots). According to her survivors, she carried two reload torpedoes forward and one aft.
  18 Jan 19431100
1112 (e)
At 1100 hours, Tritone was attacked by an American bomber which dropped a bomb. The submarine replied with her antiaircraft machine guns and escaped by diving.

This was actually Hudson ' R' of 500 Squadron piloted by Flying Officer J.R. Pugh. It was flying at a height of 3,000 feet when a surfaced submarine was sighted at 1112 hours. The position was about 40 miles NNW of the attack carried out by Hudson ' 'J' of the same squadron the previous night and it was presumed that the submarine might be the same one (it was actually Nichelio). The aircraft released a 250lb A/S bomb from 1,300 feet. The Hudson circled the sub which remained on the surface and fired a signal cartridge. A Junker 88 shortly arrived on the scene and as the Hudson was getting short on fuel, it departed the area.
  19 Jan 1943
1413A (e)

(e) 37° 05'N, 5° 22'E
At 1413A hours, the corvette HMCS Port Arthur (Lieutenant E.T. Simmons, DSC, RCNVR) was zigzagging at 10 knots, screening the convoy MKS.6 from Philippeville to Gibraltar and the United Kingdom, when the ASDIC operator obtained an echo at 1,700 yards. At first, it was thought to be doubtful but a minute later it was confirmed to be a submarine.

At 1418A hours, a pattern of ten depth charges was released and the explosion temporarily disable the ASDIC. Three minutes later two underwater explosions were heard. In the meantime, the destroyer HMS Antelope (Lieutenant Commander Sinclair, RN) joined the hunt.

At 1423A hours, the submarine surfaced about 700 yards from the destroyer and appeared to be down by the stern. HMS Antelope opened fire with her 4.7" guns and smaller armament, scoring at least three 4.7" hits, two on the conning tower and one on the pressure hull. The destroyer closed to 30 yards and attempted to send a boarding party but the submarine sank in two minutes.

This was Tritone. C.C. Paolo Monechi, three officers and twenty-two ratings were picked up by Antelope. Twenty-six men perished, including a civilian worker.

102 entries. 93 total patrol entries (11 marked as war patrols) and 17 events.

Events listed for Paolo Monechi

GH 09.03.2021: This table kept here until we make fix the possible missing events in table above

SubmarineDateTimePositionDescription
Mocenigo12 Dec 19411240
1249B (e)
37.13 N, 19.21 E
(e) 37.26 N, 19.17 E
At 1240 hours, an aircraft was sighted at a distance of 3,500 metres. Mocenigo made a recognition signal but was not answered. As the aircraft appeared to be threatening, the submarine fired two rounds from her stern gun to keep it a t bay and it flew away. This was a Malta-based Maryland of 69 Squadron on a reconnaissance mission (Flying Officer Drew).
Mocenigo18 Dec 1941111733.28 N, 24.42 E
At 1117 hours, Mocenigo sighted three destroyers, steering 020° at over 25 knots, from a distance of 14,000 metres but was unable to close for an attack.
Mocenigo24 Dec 19411030
1034B (e)
(e) 33.32 N, 24.58 E
At 1030 hours, a bomber was sighted and Mocenigo dived immediately. The submarine had reached a depth of 40 metres when three small bombs were heard to explode near by. This was Blenheim 'P' of 203 Squadron (Pilot Officer Wintle) carrying out a "Trident" patrol and had sighted a surfaced submarine steering 240° at 8 knots. The bomber circled it twice, giving it a chance to identify itself, but the submarine began crash diving when the Blenheim was completing its second circuit, without making any recognition signal.

The aircraft made a dive attack from 1,500 feet, pulling out at 500 feet and releasing four 250lb A/S bombs in a salvo. They fell within an area of 20 yards and the gunner saw them all explode just to the port side of the U-boat which was just submerged but still visible under the water. The aircraft circled the position and, after 30 seconds, a 40 yards square patch of dark brown oil appeared . In fact, Mocenigo had escaped unscathed. The submarines HMS Thunderbolt and HMS Proteus, who were in the general area, were informed of the presence of this submarine but did not make contact.
Mocenigo27 Dec 1941221635.46 N, 23.49 E
At 2216 hours, Mocenigo sighted a Spanish vessel which had left Suda and shortly after a submarine of the VENIERO class on opposite course.
Mocenigo31 Dec 1941024739.12 N, 18.20 E
At 0247 hours, a submarine of the CAGNI class was seen on a parallel course at a distance of 1,200 metres. It was not identified but was probably Dandolo.
Mocenigo18 Feb 1942121235.33 N, 15.36 E
At 1212 hours, two aircraft were sighted at 10,000 metres and Mocenigo dived. Shortly after, three explosions were heard.
Mocenigo25 Feb 19420845At 0845 hours, the submarine Serpente was sighted.
Mocenigo25 Feb 19422058At 2058 hours, an Italian steamer escorted by a destroyer were sighted at a distance of 5,000 metres. Recognition signals were exchanged. Marina Messina had informed Mocenigo of a possible encounter.
Mocenigo14 Mar 19422056
1955 (e)
37.16.5 N, 05.05.5 E
(o) 325° - Cape Carbon - 30 miles (French source).
At 1530 hours, a 5,000-ton tanker was observed zigzagging steering between 50 and 140°. The vessel appeared to leave the route assigned to French traffic. At 2056 hours, a stern torpedo (450mm) was fired from a distance of 1,500 metres. It hit the vessel on the port side. The tanker took a list before sinking very quickly. This as the Vichy French Sainte Marcelle (ex-Norwegian Vigoer, 1518 GRT, built 1935, she had been seized at Casablanca in June 1940) who had sailed from Marseilles for Tunis on 7th March. There were two men killed, and twenty-seven survivors. Following this mistake, the Pétain government stopped its adherence to the "Paris Protocols" which included the supply of trucks and other goods to Axis forces in North Africa.
Mocenigo20 Mar 19421533
1440 (e)
36.30 N, 01.23 W
(e) 36.33 N, 01.26 W
At 1350 hours, Mocenigo heard distant turbine noises but the periscope revealed nothing. At 1510 hours, the periscope finally revealed a number of vessels proceeding on a 040° course at 20-22 knots. These were identified as two aircraft carriers (type EAGLE and ARGUS), a battleship, a cruiser and ten or twelve destroyers. The submarine moved to intercept and had reached a distance of 2,500 metres, when a first attack was thwarted by the sudden appearance of two destroyers. They had not been noticed earlier and forced the submarine to a depth of 15 metres, to avoid being rammed.

The aircraft carrier, identified as HMS Eagle, passed very near the submarine before action could be taken. She was now presenting her stern at a distance of 800 metres while HMS Argus and the battleship were turning to port. Monechi decided to fire a stern salvo of three torpedoes at Eagle and immediately took his submarine deep, as two destroyers had appeared to have discovered him, and were moving to the attack. He had reached a depth of 45 metres when an explosion was heard 3 minutes after firing, followed 2 minutes later by two more. The submarine reached a depth of 75 metres, but was not depth charged.

These were indeed the aircraft carriers HMS Eagle and HMS Argus, the battleship HMS Malaya, the light cruiser HMS Hermione and nine destroyers (these were the fleet destroyers HMS Laforey, HMS Duncan, HMS Active, HMS Anthony, HMS Wishart, HMS Whitehall and the escort destroyers HMS Blankney, HMS Croome and HMS Exmoor) on their way to carry out operation PICKET, phase 1. None of the torpedoes hit. HMS Eagle observed an explosion believed to be a torpedo at the end of its run.
Mocenigo2 May 1942074037.03 N, 00.15 E
At 0740 hours, a German submarine was encountered and recognition signals exchanged. She was proceeding to the assistance of U-573 (KL Heinrich Heinsohn), who was reported in difficulty after an air attack in Quadrat CH 8218 or 37°15' N, 00°42' E. This was almost certainly U-74 (OL Karl Friedrich) who signalled at 1052 hours that she was in Quadrat CH 8137 (37°15' N, 00°10' E). Eventually, U-573 managed to reach Cartagena where she was interned, but U-74 was sunk later that day.
Mocenigo2 May 1942143437.00 N, 00.08 E
At 1434 hours, the submarine sighted a destroyer at a distance of 16,000 metres.
Mocenigo9 May 1942091237.41 N, 02.18 E
At 1434 hours, the submarine sighted from a distance of 13,000 metres a destroyer proceeding at 24 knots.
Mocenigo18 May 19420826
0828 (e)
37.05.5 N, 01.03.5 E
(e) 37.07 N, 01.05 E
At 0811 hours, an enemy formation was observed through the periscope, proceeding on a 050° course at a distance of 8-9,000 metres. It was identified as HMS Eagle, HMS Argus, a cruiser and several destroyers. Mocenigo closed to 2,000 metres and attempted an attack on Eagle but could not get a suitable track angle.

At 0826 hours, Monechi gave the order to fire three stern torpedoes (533mm) at the cruiser from a distance of 1,200 metres and heard two hits after 90 seconds. Several depth charges followed. These were indeed the aircraft carriers HMS Eagle and HMS Argus, the light cruiser HMS Charybdis screened by screened by the destroyers HMS Westcott, HMS Antelope, HMS Wrestler, HMS Wishart, HMS Partridge and HMS Ithuriel carrying operation L.B. (flying off Spitfires to Malta). HMS Charybdis reported missed by two or three torpedoes (also sighted by HMS Partridge) and dropped three depth-charges. Partridge hunted the submarine dropping 24 depth charges. The submarine was badly shaken and went down to 96 metres. The damages forced her to abandon her patrol.
Tritone18 Jan 19431100
1112 (e)
(e) 37.50 N, 05.58 E
At 1100 hours, Tritone was attacked by an American bomber which dropped a bomb. The submarine replied with her antiaircraft machine guns and escaped by diving.

This was actually Hudson ' R' of 500 Squadron piloted by Flying Officer J.R. Pugh. It was flying at a height of 3,000 feet when a surfaced submarine was sighted at 1112 hours. The position was about 40 miles NNW of the attack carried out by Hudson ' 'J' of the same squadron the previous night and it was presumed that the submarine might be the same one (it was actually Nichelio). The aircraft released a 250lb A/S bomb from 1,300 feet. The Hudson circled the sub which remained on the surface and fired a signal cartridge. A Junker 88 shortly arrived on the scene and as the Hudson was getting short on fuel, it departed the area.
Tritone19 Jan 1943
1413A (e)
(e) 37.05 N, 05.22 E
At 1413A hours, the corvette HMCS Port Arthur (Lieutenant E.T. Simmons, DSC, RCNVR) was zigzagging at 10 knots, screening the convoy MKS.6 from Philippeville to Gibraltar and the United Kingdom, when the ASDIC operator obtained an echo at 1,700 yards. At first, it was thought to be doubtful but a minute later it was confirmed to be a submarine.

At 1418A hours, a pattern of ten depth charges was released and the explosion temporarily disable the ASDIC. Three minutes later two underwater explosions were heard. In the meantime, the destroyer HMS Antelope (Lieutenant Commander Sinclair, RN) joined the hunt.

At 1423A hours, the submarine surfaced about 700 yards from the destroyer and appeared to be down by the stern. HMS Antelope opened fire with her 4.7" guns and smaller armament, scoring at least three 4.7" hits, two on the conning tower and one on the pressure hull. The destroyer closed to 30 yards and attempted to send a boarding party but the submarine sank in two minutes.

This was Tritone. C.C. Paolo Monechi, three officers and twenty-two ratings were picked up by Antelope. Twenty-six men perished, including a civilian worker.

Italian Commanders

Italian Submarines