Operation Substance

On Thursday 17 July 1941, a few minutes before half past eleven, the sirens wailed over Malta. At around 7,000 metres an Italian Savoia-Marchetti SM.79 reconnaissance aircraft, escorted by fifteen fighters, flew over the Grand Harbour and crossed the island from north to south. Heavy anti-aircraft guns fired at it and nineteen Hurricanes were scrambled. The pilots of No. 185 Squadron RAF sighted the enemy but were more than 1,000 metres too low. No. 249 Squadron chased the Italians out to sea and caught them some 90 kilometres north of the island. According to the garrison’s war diary, two Macchi MC.200 fighters went down into the sea and a third was damaged; among the dead was Sergente Maggiore Enrico Botti of the 4th Fighter Wing (4° Stormo). The British lost one Hurricane, and its pilot, Sergeant Maurice Guest, was killed.

During the night single bombers came over the island and dropped bombs around Sliema, on Ta’ Qali airfield and on the seaplane base at Kalafrana. One house in the Mensija district was reduced to rubble, but nobody on the ground was killed. This was an ordinary day on Malta in the middle of the summer of 1941: alerts, brief fighter skirmishes, bombs dropped blindly at night. Meanwhile, far away on the Atlantic, the largest convoy of supplies and reinforcements since the beginning of the war was sailing towards the island. It was the convoy of Operation Substance.

Some chronologies record under 17 July that “Luftwaffe attacks on Malta continue”. This needs correcting. The German air force had left Sicily at the beginning of June, before the attack on the Soviet Union, and in the summer of 1941 Malta was bombed and harried solely by aircraft of the Italian Regia Aeronautica. The Luftwaffe did not return over the island until December.

Malta in the summer of 1941

From January to May 1941 Malta had been attacked by the German X Air Corps (X. Fliegerkorps) of General Hans Geisler, which during the winter had all but paralysed the island. In the spring its units left one after another for North Africa, the Balkans and Crete, and the Luftwaffe drew its aircraft away to the east, where on 22 June Germany attacked the Soviet Union. The British made good use of the respite. From the spring onwards the carriers of Force H from Gibraltar repeatedly steamed to the western end of the Mediterranean and flew off fighters, which made their own way to the island; in June, beginning with Operation Rocket, more than 140 of them arrived, although many flew on to Egypt. There were now so many Hurricanes on Malta that they could not only defend the airfields but also go looking for a fight.

In July the Italians attacked mainly at night. Fiat BR.20 and SM.79 bombers came over singly or in small groups, dropped small bombs on the airfields, the harbour and the surrounding towns and returned to Sicily. The British official history describes the raids as a nuisance that did little damage. For the inhabitants, however, they could be deadly: on the night of 11/12 July bombs dropped on Ħamrun and Marsa killed eight civilians. By day reconnaissance aircraft came over Malta under a strong fighter escort, and on 11 July several dozen Macchis appeared over the island, a few of which dived to strafe Luqa airfield, destroying one bomber and damaging several others. According to a tally drawn up on the island, 72 air-raid alerts were sounded on Malta in July 1941, 53 of them at night, and bombs killed 39 civilians: 21 men, eight women and ten children. Eighty houses were destroyed or badly damaged.

Malta, meanwhile, was becoming ever more dangerous to the enemy. On 1 June Hugh Pughe Lloyd took command of the air forces on the island, with orders to turn it into a base for attacks on Axis shipping. Blenheim bombers attacked convoys sailing from Italy to Libya by day, and at night Wellingtons bombed Tripoli, Naples and Palermo. On the very night of 17/18 July, while Italian bombers were circling over the island, five Wellingtons of No. 148 Squadron bombed the harbour at Palermo, and three Swordfish torpedo bombers of No. 830 Squadron of the Fleet Air Arm attacked the harbour at Tripoli and, according to their reports, torpedoed a tanker. Submarines sailed on patrol from their base on Manoel Island. All this, however, required fuel, bombs, torpedoes, ammunition and food, and these were running low on the island. The last convoy with supply ships had reached Malta from Alexandria in May, during Operation Tiger. Now, after the loss of Crete and Cyrenaica, the eastern route lay within range of the German air force, and Admiral Andrew Cunningham’s Mediterranean Fleet, weakened by its losses off Crete, had its hands full supplying besieged Tobruk. That left the route from the west.

The plan

After the fall of Crete there were fears in London and on Malta that the island would be the next target of a German airborne assault. The Governor, Lieutenant General William Dobbie, presented the Chiefs of Staff with a list of requirements, and they agreed to send two infantry battalions, a heavy and a light anti-aircraft regiment, thirty field guns with their crews, and RAF pilots and ground crew. Because the Luftwaffe was then concentrated on Crete and in Cyrenaica, it was decided to run the convoy through the western Mediterranean. The operation was named Substance.

Six supply ships – Melbourne Star, Sydney Star, City of Pretoria, Port Chalmers, Durham and Deucalion – and the troopship Leinster left the Firth of Clyde and the Bristol Channel in the second week of July as part of the large convoy WS 9C. On board were troops, guns, ammunition, fuel, aircraft spares and food. The British expected the Italian battleships to put to sea and some 200 aircraft from Sardinia and Sicily to attack. Vice-Admiral James Somerville’s Force H – the battlecruiser Renown, the aircraft carrier Ark Royal, the cruiser Hermione and destroyers – was therefore reinforced with ships of the Home Fleet: the battleship Nelson, the cruisers Edinburgh, Manchester and Arethusa, the fast minelayer Manxman and more destroyers. The close escort of the convoy, designated Force X, was commanded by Rear Admiral Neville Syfret in Edinburgh. Force H was to accompany the ships as far as the entrance to the Sicilian Channel; beyond that, through the most dangerous stretch, the convoy was to proceed alone with Force X.

The plan also provided for movement in the opposite direction: the naval supply ship Breconshire and six empty merchant ships that had been lying in the Grand Harbour for months were to slip out of Malta to Gibraltar. Eight submarines were to lie in wait off the Italian coast in case the Italian fleet came out, Wellingtons and Blenheims from Malta were to bomb Naples and the airfields in Sicily, and Beaufighter heavy fighters, sent to the island specially for the occasion, were to cover the convoy on the final leg after Ark Royal turned back. On 17 July the submarine Utmost left Malta for her patrol position, while the ships of the convoy were approaching Gibraltar. That evening some of the escorting warships, together with two troopships, detached from the convoy and went ahead to Gibraltar.

Across the Mediterranean

On the night of 20/21 July, in a fog that was meant to hide the movement of the ships from observers on the Spanish side of the strait, the convoy – now designated GM 1 – passed through the Strait of Gibraltar. It began with bad luck: Leinster, which was leaving Gibraltar separately, ran aground in thick fog near Cape Carnero and had to return to port. As a result, about a thousand soldiers and airmen, including all the RAF personnel intended for the island, never reached Malta.

The Italian naval high command, Supermarina, long remained unaware of what was happening. On 21 July an Italian seaplane spotted Somerville’s ships, but not the convoy, and the Italians concluded that Force H was once again ferrying fighters to Malta. An operation in the east also served to divert attention: on 23 July the Mediterranean Fleet sailed west from Alexandria and turned back after dark, while two submarines transmitted dummy signals from along its former course. By the time it finally became clear that a convoy was involved, it was too late to send the Italian battleships against it. The fight was left to the air force, submarines and motor torpedo boats.

On the morning of 23 July, south of Sardinia, the first co-ordinated attack came in: high-level bombers and SM.79 torpedo bombers skimming low over the water. Fulmar fighters from Ark Royal broke up the bomber formation, but three torpedo bombers got through the screen. One torpedo struck the stern of the destroyer Fearless, which caught fire and lost power; between 26 and 35 of her crew were killed (sources give different figures). The ship could not be saved – the destroyer Forester took off her men and sank her with a torpedo. A second torpedo hit the cruiser Manchester. The explosion tore a hole more than ten metres long in her hull, disabled both port propeller shafts and killed 26 of her crew and more than a dozen soldiers who were travelling to Malta on board. The cruiser returned to Gibraltar under her own power, escorted by a destroyer. The Italians lost at least two aircraft in this attack, the British three Fulmars.

In the afternoon, at the entrance to the Sicilian Channel, Somerville turned west with the heavy ships, and the convoy sailed on with Force X, which Hermione joined in place of Manchester. Fulmars covered it until dusk, and Beaufighters from Malta after that. In the evening a bomb that fell close alongside the destroyer Firedrake stove in her plating and flooded a boiler room; she was towed back to Gibraltar. After dark the convoy, instead of keeping to the usual route past Pantelleria, turned north-east towards the coast of Sicily. Rear Admiral Syfret intended in this way to avoid new Italian minefields and to mislead the enemy aircraft. It worked: during the night the British could see flares to the south, with which Italian aircraft were lighting up empty sea along the old convoy route.

At about three in the morning of 24 July, however, two Italian motor torpedo boats, MAS 532 and MAS 533, stumbled on the convoy. In the confusion, with British ships firing in every direction and their captains reporting an attack by a dozen or more boats, one torpedo hit Sydney Star. The ship was taking on water and listing heavily. The Australian destroyer Nestor came alongside and took off some 500 men, mostly soldiers of the light anti-aircraft regiment, while the ship’s master decided to bring her to Malta with a handful of his crew. In the morning the ship and her escort were still beating off attacks by Italian bombers and torpedo bombers.

On 24 July the cruisers reached Malta ahead of the convoy, landed their troops and stores and put to sea again the same evening to rejoin Somerville. In the afternoon the convoy’s ships entered the Grand Harbour, followed by the crippled Sydney Star. Crowds of civilians and soldiers cheered them from the bastions of Valletta. Meanwhile the empty ships from Malta, which had sailed on 23 July, were slipping west along the Tunisian coast. Only the tanker Hoegh Hood was hit by a torpedo, and she too reached her destination. By 28 July they were all in Gibraltar, to which Force H had returned the day before.

The attack on the Grand Harbour

The Substance ships were still lying in the Grand Harbour when the Italians tried to destroy them by other means. Since the spring the Decima Flottiglia MAS, a naval unit equipped with explosive motor boats (PL) and human torpedoes, which in March had disabled the cruiser York in Suda Bay, had been preparing for the task. At the end of June its commander, Commander Vittorio Moccagatta, twice led the boats out against Malta, but each time heavy seas and breakdowns foiled him. Now, with the convoy’s ships in harbour, the expedition set out for the third time.

On the evening of 25 July the sloop Diana left Augusta in Sicily with nine explosive motor boats on board and a launch carrying two Maiale human torpedoes. She was accompanied by two motor torpedo boats, MAS 451 and MAS 452. The plan was daring. Major Teseo Tesei, one of the inventors of the human torpedo, was to blow up at 4.30 a.m. the steel net closing the narrow passage beneath the bridge that linked the breakwater with Fort St Elmo. The motor boats were to race through the gap into the Grand Harbour and ram the ships lying there, while the second human torpedo was to attack the submarines in Marsamxett Harbour. Italian air raids were to distract the defenders.

The defenders, however, knew that something was coming. As early as about 10.30 p.m. on 25 July a British radar set on Malta detected a large contact to the north, and according to some British writers signals intelligence had given a warning even earlier. The gunners stayed at their posts and slept beside their guns. The Italians, meanwhile, were losing time to breakdowns, and the second human torpedo turned out to be damaged. Tesei set off with his companion, Alcide Pedretti, almost an hour late. According to Italian accounts, he said that the net would be blown at 4.30 even if he had to blow himself up with it.

At 4.30 there was no explosion. A quarter of an hour later the commander of the motor boats, Lieutenant Commander Giorgio Giobbe, sent two boats against the net. Roberto Frassetto jumped clear of his boat before the target; Aristide Carabelli stayed at the helm. At about 4.48 both boats exploded beneath the bridge. The blast tore the net away, but it also brought down a span of the bridge, which fell into the water and blocked the passage more tightly than any barrier. Searchlights came on and the six-pounder guns of the Royal Malta Artillery in Fort St Elmo and Fort Ricasoli opened fire, together with the machine guns of the Cheshire Regiment. Within minutes the motor boats racing towards the blocked entrance had been sunk or smashed; their pilots were killed or, wounded, swam ashore and were taken prisoner. Tesei and Pedretti were killed. According to the version accepted in Italy, Tesei detonated his charge at once, sacrificing himself to open the way; some researchers, including the Maltese historian Joseph Caruana, believe that his torpedo was hit by a shell from a gun at Fort St Elmo.

At dawn some thirty Hurricanes took off. They attacked the retreating motor torpedo boats, the explosive boats and the Italian Macchis flying from Sicily to cover the withdrawal. A shell that hit the wheelhouse of MAS 452 – fired, according to some sources, by a Hurricane and, according to others, by a gun at Fort St Elmo shooting at the limit of its range – killed, among others, Moccagatta, Giobbe and the expedition’s doctor, Captain Bruno Falcomatà. Strafed by the fighters, MAS 451 caught fire and blew up. The British lost one Hurricane. Its pilot baled out, swam to the drifting MAS 452, on which lay the bodies of eight sailors, and waited on board until a seaplane picked him up; the boat was later towed into harbour. According to Italian figures, 15 men were killed and 18 taken prisoner; of those who approached Malta, only eleven sailors from MAS 452, who escaped in a small command launch, made it back to Sicily. Not a single British ship was damaged. The British official history judged the attack a complete failure, while in Italian writing it came to be known as a “glorious defeat”: nine of its participants, most of them posthumously, were awarded the Gold Medal of Military Valour.

Place in the war

For the British, Substance was a success bought at small cost. All six supply ships reached Malta, and the empty ships from the island reached Gibraltar. One destroyer was sunk, and Manchester was out of action for ten months, because she had to be repaired as far away as Philadelphia. According to some studies, about 65,000 tons of supplies were delivered to the island in July. The soldiers and airmen left behind in Gibraltar after the Leinster accident, and those who had returned there aboard the damaged warships, were carried to Malta between 31 July and 2 August by the cruisers Hermione and Arethusa, the minelayer Manxman and two destroyers in the swift Operation Style; on the way Hermione rammed and sank the Italian submarine Tembien off Pantelleria. According to the British official history, in August the Malta garrison numbered more than 22,000 men in thirteen battalions, three of them Maltese; the island had 112 heavy and 118 light anti-aircraft guns, stocks of most military stores for eight months, and of some for as long as fifteen, and 75 serviceable Hurricanes.

Thanks to this, throughout the second half of 1941 Malta was able to do what Rommel and the Italian high command feared most: sink the ships carrying supplies to the Axis forces in Libya. In the autumn its aircraft and submarines were joined by the cruisers and destroyers of Force K, and the losses suffered by convoys bound for Tripoli and Benghazi weakened Rommel’s army before the British Operation Crusader in November. In September another large convoy, Halberd, passed through the western Mediterranean. The attack on the Grand Harbour put the Decima Flottiglia MAS out of action for several months, but did not break it: in December 1941 its human torpedoes badly damaged the battleships Queen Elizabeth and Valiant at Alexandria.

The respite that the departure of the Luftwaffe and the July convoy gave Malta proved short-lived, however. In December 1941 a strong German air force under Field Marshal Albert Kesselring returned to Sicily, and in 1942 the island endured the heaviest bombing in its history and came close to starvation before a convoy from Alexandria broke the siege in November. July 1941, when only Italian aircraft flew over Malta and six fully laden ships entered the Grand Harbour, was one of the few good months in the history of the siege.