The Raid on Grand Harbour (), was an Italian raid against Allied shipping in Grand Harbour, Valletta, Malta in the early morning of 26 July 1941 during the Second World War. MTM explosive motorboat pilots and Frogmen from the ( 10th Flotilla Torpedo Armed Motorboats) of the conducted a raid to penetrate the harbour and attack British shipping. The attackers destroyed the St Elmo Bridge trying to enter the harbour, before being driven off by fire from the coastal defences.
The group was killed outside the harbour by the British harbour defences during the raid, swam ashore to be taken prisoner or were killed attempting the return journey; it was the worst defeat suffered by in the war. Many of the two MAS-boat (, torpedo-armed motorboat) crews and surviving men were killed when British Hurricane fighter aircraft attacked the MAS-boats on the morning of 26 July, along with two Macchi C.200 Saetta (Lightning) fighter escorts shot down in dogfights. A Hurricane was shot down and the pilot rescued from MAS-452, which was recovered and used as a tender by the British.
Background
The interest of the in small boat warfare and other , stealth and deceit, lay dormant between 1918 and the diplomatic crisis with Britain over the Second Italo-Ethiopian War 1935–1936. In 1935 and early 1936, Captain Teseo Tesei and Captain Elios Toschi tested a human torpedo in La Spezia on the Tyrrhenian Sea and resumed testing in May. The Ethiopian defeat in 1936 ended the tests but work on assault boats continued. On 28 September 1938, ordered the I (1st Torpedo Motorboat Flotilla), based at La Spezia, to establish a research department (the (Special Weapons Section) from 1939. The detachment had a few officers at HQ, seven at a confidential base at Bocca di Serchio for human torpedo and frogman training and another six officers to pilot the assault motorboats, of which seven had been built, plus eleven human torpedoes.
On 24 February 1940, the 1st MAS Flotilla and the Special Weapons Section was taken over by Commander Mario Giorgini and in August attempts to use the unconventional weapons began, with little success and the capture of Giorgini in October. On 23 January 1941 Commander Vittorio Moccagatta replaced Giorgini and on 15 March formed the (10th Flotilla, Torpedo Armed Motorboats, ). The new force had a HQ, including a plans office and a weapons section. The surface assault boats and the training school (Lieutenant-Commander Giorgio Giobbe) were split from the human torpedoes and other underwater weapons (Lieutenant-Commander Junio Valerio Borghese), the captain of the . remained at La Spezia and an advanced base was set up in Augusta, Sicily.
Raid on Souda Bay
The MTMs got past a net barrage and rendezvoused near an islet in the mouth of Souda Bay, the MTM pilots using oars to move quietly. The commander called the boats together and resumed the advance towards the third net barrage, about away. The commander, Faggioni, briefed the pilots; two were to attack the heavy cruiser York, about away; Faggioni and another MTM pilot waited in reserve in case the attack failed. Soon after 05:00, as dawn was breaking, the first two MTMs moved to about from York, waited for another fifteen minutes for the sky to clear, then sped towards the cruiser, the pilots abandoning their MTMs about from the ship. At 05:11 an officer on York heard an engine, mistook it for an aircraft and before he could raise the alarm, the ship was hit. Encouraged by this success, was ordered on 26 April to plan a similar attack on Grand Harbour.
Valetta
Valetta Harbour is bisected by a peninsula on which lies the city of Valetta. Marsamxett Harbour, to the north, housed the submarine base. Grand Harbour, to the south, the main harbour, had the main naval base and the commercial harbour. The entrance to Grand Harbour in 1941 was protected by Fort Saint Elmo at the end of the Valetta peninsula and by Fort Ricasoli at the eastern side of the entrance, with a breakwater jutting from each side. The gap between St Elmo and Ricasoli was about . The short, eastern, breakwater ended at the rocks under Fort Ricasoli. The longer, western, breakwater had a -gap at the shore end under Fort St Elmo, for small craft. A bridge spanned the gap, resting on a central pylon and a steel torpedo net had been suspended from it down to the seabed. The main entrance between the breakwaters was blocked by a boom from the inner side of St Elmo to the tip of the Ricasoli-side breakwater.
St Elmo had six twin 6-pounder guns manned by the 3rd Coastal Battery, Royal Malta Artillery (RMA, battery commander Colonel Henry Ferro) and Ricasoli had three 6-pounders manned by the 1st Coastal Battery RMA. The guns had been emplaced on the bastion walls, about above sea level. There were many searchlights and a machine-gun post had been built on the rocks under Ricasoli, manned by troops of the 1st Battalion, Cheshire Regiment. The entrance had been divided into zones for each 6-pounder; targets in other zones were not to be engaged unless the gun had an empty zone. The guns were a recent addition and had been intended to have a fire control director but the ship bringing it had been sunk, leaving the guns were under local control. The 6-pounders fired special anti-flash ammunition, to avoid blinding the gun-layers at night but concealing the flash produced huge clouds of smoke.
Reconnaissances were conducted off Valletta during the nights of 25/26 and 27/28 May, with encouraging results, the MAS had approached within of Valletta, with the Malta coast defences apparently quiescent. postponed an attack on 30 May and was ordered to wait until the next new moon in towards the end of June 1941. The attack was given the code-name Another reconnaissance by MAS boats during the night of 25/26 June came within without alerting the shore defences, leading the to look on the attack with greater optimism. departed from an advanced base at Augusta in Sicily on the afternoon of 27 June with five MAS towing nine MTM; a MTS and a MTM were towed by MAS-452. Two MTM each were towed by MAS-451, -509, -556 and -562. Rough seas swamped an MTM and the force turned back.
Another attempt with eight MTM was made on 29/30 June. MAS-452 towed the MTS and the other MAS towed two MTM apiece. The weather was too rough and a damaged MTM was sent back to Augusta, towed by its MAS, the other MTM being taken over by MAS-452. The weather abated after night fell but at 21:00 one of the MTM tow cables broke and the MTM engine failed, making it impossible to catch up for the tow to be rejoined. After an hour of fruitless attempts to get the engine going, it was scuttled at 22:00 and the mission was resumed. Only five minutes after resuming the journey, one of the MAS suffered an engine failure and took twenty minutes to get going, by when it was too late to attack before dawn. The raiders reversed course and the attack was postponed again, until new moon period the end of July.
Prelude Plan, MALTA-2
For the next attempt on Grand Harbour, the attack was re-named . The attack was scheduled for the night of 25/26 July 1941. The earlier operations had shown that MTM could not make the sea crossing to Malta and the number of MAS was reduced to MAS-451 and MAS-452. The aviso was to tow the MTL and carry the nine MTM and an MTS. Getting into the harbour was made easier by adding two , carried by the MTL, for surprise. A was to explode a charge against the torpedo net at 04:30 and the MTM would pass in line-ahead through the gap in the inner-boom.
Once through the boom, the MTM would speed into the harbour, to attack ships at their moorings and the other would attack the submarines at Marsamxett Creek. Small air raids at 02:30 and 04:15 on Valletta by the would be useful navigational aids to . The third air raid was to be a bigger effort, just inland from Valletta, at 04:30 to serve as a diversion when attacked. It was hoped that the noise of the British anti-aircraft guns would mask approaching boats. At 05:30 fighters would take-off from Comiso in Sicily, to escort the returning boats. A MAS reconnaissance sortie off Malta during the night of 23/24 July closed to within of the coast. Four searchlights scanned the sea but missed the MAS, which made its way slowly back northwards to safety.
On 24 June, Convoy GM 1 from Operation Substance arrived at Malta, guaranteeing that Grand Harbour would contain plenty of targets. Nineteen men of and 2 MAS with 13 crew each, left Augusta at 18:15 on 25 July 1941, with Diana, MAS-451 and MAS-452, nine MTM, a small 2-man MTS command/navigational boat and an MTL loaded with the two . Diana towed the MTL and carried the MTM and the MTS with MAS-451 and MAS-452 close by. The weather was perfect, with a slight north-westerly breeze and a calm sea. Moccagatta was in command in MAS-452 and Giobbe commanded the MTM and directed the attack from the MTS. At 23:00 hours on 25 July, at Point C north of Valletta, Diana stopped, launched the MTS and the MTM, which took about an hour; an MTM was damaged. At midnight Diana turned northwards for Sicily, to await the MAS off Cape Passero.
The MAS escorted the MTM, MAS-451 towing the MTL; hardly had the tow begun when the tow rope fouled the propeller of MAS-451 and the boats collided; one of the might have been damaged but not noticed at the time. Trying to free the propeller of MAS-451 was fruitless and after an hour, the crew was ordered back to Sicily. pressed on but the delay had been serious; MAS-452 took over the tow of the MTL. Moccagatta got the boats moving faster than planned, the damaged MTM dropped back and had to be scuttled, the pilot, Montanari, going aboard MAS-452. After half an hour MAS-451 turned up, the crew having freed the propeller. The first raid by the at 01:45 did not appear and just after 02:00 on 26 July reached Point B, north of Valletta, not the planned arrival at 01:34. The MAS stopped and the eight MTM, led by Giobbe in the MTS, sailed southwards towards Valletta, in line-ahead at , the maximum speed of the MTL, which reduced the wakes and noise of the boat engines.
The Italian force had been detected by radar several hours earlier; a temperature inversion, which makes radar waves curve over the horizon, had extended the radar range from Malta. At 22:30 hours on 25 July, 502 RAF Radar station, at Fort Madliena, detected a strong echo to the north-east, the defences were alerted and gun crews closed up. The echo faded at 23:00 and around midnight it moved northwards towards Sicily, leaving behind a small indeterminate echo, which faded away as the strong echo moved out of range. The gun crews and searchlight personnel were stood-down but had to stay close by their equipment. The men slept in the gun emplacements, guns loaded and the searchlights were also held at 30-second readiness, directed to create an illuminated area in front of the harbour entrance. The guns at Fort St Elmo and Fort Ricasoli remained ready for action and at 02:45 an Italian aircraft flew north-west to south-east over Malta and bombed over from Valletta.
Attack Approach to Valetta