The Battle of Grand Harbour, also known as Operazione MALTA-2, was an unsuccessful Italian raid against Allied shipping in the harbour of Valletta, Malta on the night of 25-26 July 1941 during World War II. Italian Regia Marina (RM) commando frogmen from the Decima Flottiglia MAS ("X-MAS") attempted to penetrate the harbour to attack British shipping. The attackers destroyed the St Elmo Bridge trying to enter the harbour before being driven off by fire from coastal defences. The Italians suffered heavy casualties; the entire X-MAS group was killed or captured.

Background

Italian attempts and preparations

In late-March 1941, X-MAS sank an Allied cruiser and tanker off Crete during the Raid on Souda Bay using explosive boats (MT). Encouraged by this success, X-MAS was ordered on 26 April to plan a similar attack on Grand Harbour. Night reconnaissance by motor torpedo boats (MAS) during the new moon at the end of May got within  of the coastal defenses without eliciting a reaction.

The attack was authorized to proceed during the new moon at the end of June as Operazione MALTA-1. MAS reconnaissance on the night of 25/26 June approached to  without incident. The first attempt launched from Augusta, Sicily on the afternoon of 27 June with five MAS towing nine MT and a MTS-type torpedo boat; it was forced back by poor weather. Another attempt was made on 29/30 June but it too was aborted after delays from poor weather and problems with tow lines and engines.

The attack was postponed to 25/26 July as Operazione MALTA-2. The plan was modified based on the previous attempts. The number of MAS was reduced to two, MAS-451 and MAS-452. Two human torpedoes (SLC) were added, carried by a MTL-type boat. The aviso Diana was added as a mother ship; she would tow the MTL and carry nine MT and a MTS. One SLC was added as a stealthier method of making a hole in the steel anti-torpedo net suspended under the St Elmo Bridge; the net prevented the MT from passing into Grand Harbour. The other SLC would enter Marsamxett Harbour and attack Allied submarines at Lazaretto Creek. The Regia Aeronautica would launch three air raids; the raids at 02:15 and 04:15 would be navigational aids for the naval group; the 04:30 raid, striking inland of Valletta, would coincide with the opening of the steel net, diverting attention from and masking the noise of the naval group.

On the night of 23/24 July, a MAS patrol approached to  of the Maltese coast before the British turned on searchlights; the Italians were not seen.

Commander Vittorio Moccagatta exercised overall control from MAS-452, with Lieutenant-Commander Giorgio Giobbe commanding the MTs from the MTS. The SLC attacking the St Elmo Bridge net would be Teseo Tesei, one of the SLC designers. The other SLC was piloted by Franco Costa.

British preparations
The two main fortifications at the entrance to Grand Harbour were Fort Saint Elmo to the north at the tip of the Valletta peninsula, and Fort Ricasoli on the opposite southern shore. The forts were manned by the Royal Malta Artillery and armed with six and three 6-pounder guns respectively. The 1st Battalion of the Cheshire Regiment manned searhlights and machine guns along the Ricasoli shore.

In mid-July, the British learned through Ultra that the Italian were planning a minor naval raid on "an island". The coincidental timing with Operation Substance made the British wary of unusual Italian naval activity near Malta.

On 24 June, convoy GM 1 from Substance arrived at Malta and became targets for the Italian raid.

Battle

Delays and radar detection
The Italian force left Augusta with 19 X-MAS and 26 boat crew at 18:15 on 25 July. The journey south was in good weather. The Royal Air Force (RAF) radar at Fort Madalena detected the Italian squadron at 22:30 about  northeast of Malta and put the defences on alert. The alert lasted until sometime after 23:00 when the radar echos faded, although gunners and searchlight crews remained near their stations as a precaution. Radar ranges were unusually long that night due to a temperature inversion. Diana detached its boats  north of Valletta between 23:00 to midnight, then returned north to wait for the raiders off of Capo Passero. One MT was damaged during unloading. MAS-451 took over towing the MTL. Almost immediately one of the MAS's propellers was ensnared by the towline and the boats collided. One SLC - later used by Costa - was likely and unknowingly damaged making it difficult to control. The propeller could not be freed after an hour and the tow was transferred to MAS-452. MAS-451 was ordered to return to Sicily. Speed was increased to make up for lost time, leading to the damaged MT falling behind and being scuttled. Half an hour later MAS-451 rejoined the group having freed the propeller.

The Italians were  north of Valletta shortly after 02:00 on 26 July, behind the scheduled 01:34. The MAS remained here while the MTL and MT went onward at the MTL's maximum speed of . The planned air raids did not help navigation; the 01:45 attack did not occur, and the 02:45 raid by a single aircraft missed Valletta and went unnoticed by the raiders. The MTs arrived  off of St. Elmo shortly after 03:00 where they would wait for the explosion at the bridge to being their attack. The MTL launched the SLCs about  closer to shore; the launching took a long time. The Italians did not realize that the westerly sea current was pushing the stationary SLCs and MTs eastward and away from the bridge.

Destroying the bridge

The damage to the SLC was discovered and Tesei could not repair it. Tesei ordered Costa to return to the MTL and scuttle the torpedo, but Costa disobeyed orders and attempted to carry out the attack. Tesei started his attack at 03:45, about an hour behind schedule. He could not reach the bridge, or demolish the net using the SLC's detachable warhead and a time-delay fuse , by 04:30. Tesei told Costa that an instantaneous fuze would be used if time required it. The third air raid by two planes occurred early at 04:13 and only served to wake the defenders. 

The MTs moved  closer to shore at 04:12. No explosion occurred. At 04:40, Giorgio ordered two MTs forward to destroy the net. The first MT was moving too slow and became snared in the net rather than breaking up and exploding; its pilot abandoned the boat as the attack went in and was later captured. The second pilot set the fuze to instantaneous, stayed aboard to ram the net at full speed, and was killed as both MTs exploded at 04:48. A bridge span collapsed, and its wreckage replaced the destroyed net as a sturdier block. The explosion put the defences back on alert. Shortly after the explosion, a 6-pounder at Fort Saint Elmo fired at a tiny bow-wake moving toward the bridge  away and causing the unidentified object to explode. The explosion was likely caused by the warhead of Tesei's SLC, and how he was killed; an Italian breathing mask with hair and skin attached was discovered nearby in the morning.

Retreat
The explosion at the bridge was the signal for the MTs to attack. They were quickly illuminated by searchlights near the bridge and came under intense fire from the defences. Two MTs were destroyed; their pilots were wounded and later captured. The remaining four MTs retreated northward after realizing that they could not enter the harbour and attempted to regroup. The British ceased firing near the bridge at 04:52. A pair of MTs, one with a wounded pilot overboard remained near the edge of the illuminated area and within sight of the British. Initially, the boats were stationary and appeared abandoned, but at 05:20 the sudden movement of one toward the other caused the British to fire upon them for a minute. The boats were destroyed; both Italian pilots reached shore and were captured. At about this time Giobbe reached the MASs. MAS-451 set course for Sicily, while MAS-452 took the MTS under tow and headed south, likely to rescue survivors.

Shortly after 05:30, 30 RAF Hawker Hurricanes from 126 and 185 Squadrons took off to hunt the Italian raiders. A Hurricane strafed MAS-452 and eight attacked the remaining pair of MTs. Both MTs were scuttled after the attack; one pilot died doing so, and the other swam to Malta and surrendered. The RAF fighters were soon directed northward to meet ten Italian Macchi C.200 Saettas from 7 Gruppo and a dogfight started around 05:50. One Hurricane and two Saettas were destroyed. One Italian pilot was killed and the other was rescued by an Italian boat.

MAS-452 arrived  off of St. Elmo shortly before 06:00, and was spotted shortly after at dawn fired upon afterwards by the fort. The boat was hit by a 6-pounder firing from beyond theoretical maximum range; the shell, fired on a flat trajectory, ricocheted off of the surface of the water and exploded in the wheelhouse. Moccagatta, Giobbe, the rest of the X-MAS leadership, the boat's commanding officer and helmsman were killed. The remaining 11 crew members feared the MAS would sink and evacuated on the MTS; they returned to Sicily. MAS-452 was attacked by Hurricanes at around 06:20  northeast of Malta. The boat was immobilized and the fuel tank hit and set on fire. Three crew members were killed. The nine remaining crew, including the wounded commanding officer, abandoned the boat, which exploded at 06:40; they were rescued by a civilian Royal Army Service Corps (RASC) launch later in the morning. The MTL had delayed escaping for too long and was discovered at 06:40  northeast of Malta; it was attacked by a Hurricane directed by gunfire from Fort Saint Rocco and sunk. The pilot was wounded and captured. The mechanical difficulties with his SLC prevented Costa from making any progress; he and his crewmate scuttled the torpedo after the controls failed at 08:00 and then swam ashore near St. Andrew's and surrendered.

The British pilot of the downed Hurricane paddled toward Malta on a dinghy before finding and boarding the abandoned MAS-452. Enthusiastically waving the Italian flag attracted the attention of the RASC launch that rescued the crew of MAS-452, but the launch was ordered to return to base upon reporting the "aggressive" flag waving. The pilot was rescued around noon by a RAF Fairey Swordfish floatplane.

Aftermath

The Italians failed to achieve any of their objectives. None of the 19 X-MAS personnel escaped; 10 were killed and nine were captured. Of the 26 MAS crew, six were killed, nine were captured, and 11 escaped to Italy where one later died of wounds. Moccagatta and Tesei were posthumously awarded the Gold Medal of Military Valour. In addition, one air force pilot was killed. Equipment losses included all of the boats and torpedoes, except for the MTS, and two Saetta fighters. Further X-MAS operations were delayed by the loss of so many senior officers, but in December it raided Alexandria and sank the battleships  and .

The British lost one Hurricane fighter. They also captured MAS-452 - towed in by HMS Jade - one MT and Costa's SLC. The MAS was renamed X-MAS and used as an RAF rescue launch or a tender. The MT was sent to Britain for evaluation in September 1943.

The St Elmo Bridge was not repaired. The collapsed span was removed after the attack, and the rest of the bridge was demolished after the war leaving only the central support column. A new bridge opened in 2012.

References

Sources
 
 

Grand Harbour, battle of
Conflicts in 1941
Siege of Malta
Battle of Grand Harbour
World War II campaigns of the Mediterranean Theatre
Naval aviation operations and battles
Battle of Grand Harbour
Battle of Grand Harbour
Battle of Grand Harbour
Military history of the British Empire and Commonwealth in World War II