Early operations in the Mediterranean demonstrated that engagments between surface vessels, despite being spectacular, rarely provided definitive effects. Soon, it was demonstrated that control of the sea corresponded to dominance in the air. Therefore, the Regia Aeronatica had to bear ever-heavier responsibilities.
Since the beginning, aerial attack on ships was conducted by bombers which, despite being highly accurate, lack enough destructive power, thus demostrating the disproportion between the means and the results.
On August 27, 1940 Lieutenant Buscaglia completed the first Italian attack employing a torpedo, thus making operational the most dangerous attack weapon against the Royal Navy.
The first experimental launches of airborne torpedoes dated back to 1914. Nevertheless, Italy entered the war without a single squadron of torpedo launchers. After the end of World War I, attempts to employ aerial torpedoes were not successful due to inadequate equipment, faulty techniques, and limited support from the military hierarchy, experiments continued. Several aircraft were used , from the Caproni Ca. 33, to the Macchi M.24 and the very latest S.55. Later on, experimentation continued on the Cant Z.506 with the dual role of torpedo bomber and bomber, even though the time of the flying boat had already reached its azimuth.
Meantime, the war had already started, and during the encounter off Calabria, British torpedo bombers made their foray into the Mediterranean aboard aircraft carriers. Despite lack of success, it was possible to anticipate the potential of this terrible new weapon. Confirmation of this potential was dramatically evident the night of November 11, 1940 when British Swordfish launched from the aircraft carrier Illustrious inflicted a terrible strike against the Italian fleet in the harbor of Taranto, dramatically altering the balance of power in the Mediterranean.
Meantime, the “Reparto Sperimentale Aerosiluranti” (Experimental torpedo-bomber group) assembled in Gorizia at the beginning of 1940 received the Savoia Marchetti SM.79 which, although not originally designed as a torpedo bomber, was a strong, fast and maneuverable aircraft far superior to the British Swordfish. During the entire conflict, the British “Gobbo Maledetto”, (“Damn Hunchback”), so named for the unusual shape of the fusilage), became the standard aircraft used by all the torpedo bomber Squadrons, representing an insidious and dangerous presence for allied shipping.
Savoia Marchetti SM.79
The Savoia Marchetti SM.79 was designed during the mid-thirties as a military version of the civilial transport SM.79P. This tri-motor, with a mixed structure (wood and metal), won several speed and endurance records thanks to its 750-HP Alfa Romeo 126 RC.34 engines.
The military version was equipped with three 12.7 mm and one 7.7 mm machine guns. Ordinance included bombs loaded into an internal bomb bay plus two torpedo supports under the wings. It was first used in combat during the Spanish Civil War where it demonstrated high maneuverability and speed even though it was too light and, at times, unstable. It was capable of continuing flying with just two engines, capabilities which were of great use during engine failures. Excellent also was the ability of the plane to float, thus giving its crew enough time to bail out in case of forced sea landing.
On August 10, 1940 after a summary preparation, the only five SM.79 belonging to the “Reparto Sperimentale Aerosiluranti” were transferred to the airport of Ciampino, just outside Rome. From here, they were then transferred to El Adem, from where the first mission against Alexandria took place. The attack, which contemplated a simultaneous attack from two directions, against units in port, was not very successful mostly due to the shape of the harbour itself and to adverse weather conditions.
In the following months, Italy created more units and refined its weapons and techniques. Meantime, making up for all the time wasted in the previous years, during 1941 the Regia Aeronatica began harvesting the first results, hitting 30 units and sinking 9. Unfortunately, the price paid was very high and of the 260 aircrafts used, 14 were shot down and 46 damaged. Post-war statistics revealed that on average, a crew was shot down after just three missions.
Noteworthy missions took place in 1942 with the massive attack on a Malta-bound convoy, the Second Battle of Sirte, Mid-June, Mid-August. Along with the increased activity came an ever more furious reaction from antiaircraft units.Meantime, the Italian aeronautical industry was trying to improve on the SM.79 by installing more powerful engines, updating on-board equipment, and by increasing autonomy through the installation of fuel tanks in the bomb bay.
The limitations imposed by the original design of the aircraft for civilian use were many, so in 1940 it was decided to begin working on a successor, the Savoia Marchetti SM.84. The original design was ingenious, utilizing some of the existing and highly tested components already in use on the SM.79 and developing others. In fact, the SM.84 would have the same wing of the SM.79, but more powerful engines, the Piaggio P.XI RC.40, capable of 1000 HP. The fuselage was completely redesigned, introducing a spit tail thus offering more advanced defensive control. In addition, the internal defense armament was replaced with 4 12.7 mm guns.
Unfortunately, the SM.84 did not have the flying characteristics of its predecessor and it was prone, during take off, to go face down and in general, it was hard to maneuver. Despite these faults, the SM.84 was assigned to the torpedo launcher squadrons in January 1941. The 41° Stormo, so equipped, was transferred to the Aegean where it was operational until 1942 with very few positive results.
During September 1941, the SM.84s of the 282°Squadriglia based in Sardinia were deployed against a convoy which had left Gibraltar and were able to seriously damage the battleship Nelson, a cruiser and another unit. But the missed intervention of the Regia Marina made the sacrifice superfluous. Later on, a new version of the plane, the SM.84 bis was released, but without the expected results. So, in 1942 this new model was used as a torpedo bomber, but soon after removed from service. On September 8, 1943 30 SM.84s were captured by the Germans and mostly destroyed. The SM.79s survived the armistice and were utilized by the German-controlled “Repubblica Sociale Italiana” until the end of the war.
The torpedo utilized by the torpedo bombers were the 450/170/4.5 built by the Whitehead of Fiume and by the Silurificio Italiano di Baia (Naples). Both models had a range of 3,000 meters at 40 knots. The torpedo was usually launched at a speed of 300 km/h and at an altitude of 30 to 40 meters. From this height, the torpedo would enter the water at an angle of about 30° and, after having sunk about 10 meters, would, within 160 meters from the launch area, stabilize on its course and depth.
During the war, several torpedos were modified to fit the need of an aerial launch and they incorporated interesting and innovative solutions.It should be mentioned that during the war Italy built several prototypes utilizing various aircraft, such as the smaller Ca.313 and Ca.314, although too underpowered for the task. Also the Re.2002 was equipped with a torpedo shortened to 2.38 meters, and so was the very new Fiat G.55. These solutions were later implemented after the war