First time unlucky – the loss of Iride 22 August 1940

First time unlucky – the loss of Iride 22 August 1940


As we are getting closer to the date of the most successful commando raid in World War 2, the attack by the Regia Marina’s Xa MAS Flotilla on Alexandria harbour, a short reminder that this was not the first time the Italian navy tried to attack Alexandria harbour. An earlier attempt had been made in August 1940 by the 1a MAS Flotilla, shortly after Italy’s entry into the war. It was prevented by the Royal Air Force and the Fleet Air Arm, in an attack similar to that undertaken on Taranto in November 1940.

Sommergibile Iride

Perla-class Iride prior to conversion to human torpedo carrier. Wikipedia

22 August 1940

The attempt in 1940 was named Operation GA.1. The submarine to deliver the Maiale (pig) human torpedoes to Alexandria was Perla-class boat Iride, a relatively modern 600-ton boat designed for the Mediterranean. She had just finished conversion, and was being prepared for her mission in the Gulf of Bomba, near Ain-el-Gazala on the Libyan coast, west of Tobruk. Two other vessels, the auxiliary minelayer Monte Gargano and the Spica-class Torpedo Boat Calipso  were present as well. Calipso had brought the Maiale and Monte Gargano was to act as store ship for the mission.

MN Monte Gargano2

Brioni-class auxiliary early in the war, possibly Monte Gargano. Wikipedia.

2560px RN Alcione

Torpedo boat Alcione, name sake of the Spica sub-class to which Calipso belonged. Wikipedia.

Three RAF Blenheims had struck targets around Bomba Bay earlier in the day and noted the concentration of navy vessels in the bay. Reporting on their return, a Sunderland flying boat was despatched to undertake a reconnaissance. The Sunderland confirmed this concentration of targets and the strike was put on. While it is sometimes claimed this strike was the result of signals interception, there is no evidence for this.

The strike force consisted of three Fairey Swordfish of No. 824 Squadron F.A.A. of HMS Eagle. They attacked during the afternoon and sank the Monte Gargano, off which Iride had been taking on stores, and also damaged Tp Calipso. Most importantly however, they also struck Iride, which carried the men and equipment of the Italian navy’s frogmen unit 1a MAS, who were ready to attack Alexandria.

AWM 072930 Blenheim I Flight

Blenheim Mk. I in flight. AWM.

A Fairey Swordfish in Flight TR1138

Fairey Swordfish in Flight, 1943. Wikipedia.

While the strike was successful, the waters of Bomba Bay are shallow, and as Iride sank in them, she was not beyond salvage and rescue attempts. Under the leadership of the Xa MAS officers and men with their diving equipment, the Maiale could be salvaged and also seven survivors were rescued from the stern section of the sunken submarine by the specialists of 1a MAS. Two of these died however. In total therefore, 35 crew including some from 1a MAS were lost. The strike on Alexandria was off. Iride was never salvaged, and rests on the bottom of the bay in 18-20m depth, on her flank.

While the Swordfish also claimed Tp Calipso, she was not damaged and continued to operate until lost on a mine on 5 December 1940. While sometimes claims are made that four ships were sunk with three torpedoes on this day, only two were actually sunk in a nevertheless highly successful and impactful operation. While the Italians claimed that fire from Calipso had damaged at least one Swordfish so heavily that she was on fire, in reality it appears there was only slight damage to one of the planes, and they all made it back.

Relitto Mte Gargano1

Wreck of Monte Gargano in Bomba Bay, showing the shallowness of the waters. Wikipedia.

The 1a MAS Veterans

The Regia Marina continued with special operations. Almost immediately, in September 1940, a new strike was ordered, GA2. This was to be carried out by submarine Gondar, a sister of Scire. She moved out to Alexandria, but it was then noted that the Mediterranean Fleet was at sea and the strike was called off. Due to another stroke of bad luck, she came across the Australian HMAS Stuart, which conducted sonar sweeps while on an early return from the fleet operation to Alexandria, due to engine trouble. Following a long chase with considerable depth-charging, Gondar was forced to the surface, and her crew captured, including the four Maiale crews.

Following this second failure, the Regia Marina also used explosive motor boats. These attacked and sank the heavy cruiser HMS York in Suda Bay in Crete in March 1941. In summer of the same year, an operation was planned against Malta. This went disastrously wrong, as the defenders were alerted to the attack by Radar, and it cost Tesei his life. The Italian frogmen command is now named after him.

Irides mission was eventually carried out 16 months later on 19 Dec 1941, with very great success by submarine Scire. On this occasion, De la Penne on this occasion heavily damaged HMS Valiant in Alexandria harbour.

De la Penne survived the war and today has a class of two DDGs of the Italian navy named after him. 

Iride however was lost in August 1942 while attempting a strike on Haifa, which had become the emergency port for some of the Mediterranean fleet after the Axis advance to the El Alamein line. She was picked up by Royal Navy destroyers and sunk by gunfire, with all of her crew lost.


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Two pictures of de la Penne. Italian Navy.


De la Penne

Teseo Tesei. Italian Navy.


Further Reading