Battle of Taranto - Origins

Origins

Long before the First World War, the Italian Royal Navy's First Squadron was based at Taranto. In that period, the British Royal Navy developed plans for countering the power of the Regia Marina (Italian Navy). Blunting the power of any adversary in the Mediterranean Sea was an ongoing exercise. Plans for the capture of the port at Taranto were considered as early as the Italian invasion of Abyssinia in 1935.

During 1940–41, Italian Army operations in North Africa, based in Libya, required a supply line from Italy. The British Army's North African Campaign, based in Egypt, suffered from much greater supply difficulties. Supply convoys to Egypt had to either cross the Mediterranean via Gibraltar and Malta, and then approach the coast of Sicily, or steam all the way around the Cape of Good Hope, up the whole east coast of Africa, and then through the Suez Canal, to reach Alexandria. Since the latter was a very long and slow route, this put the Italian fleet in an excellent position to interdict British supplies and reinforcements.

The British had won a number of actions, considerably upsetting the balance of power in the Mediterranean. Following the concept of a fleet in being, the Italians usually kept their warships in harbour. The Italian fleet at Taranto was powerful: six battleships (of which five were battleworthy), seven heavy cruisers, two light cruisers and eight destroyers, making the threat of a sortie against British shipping a serious problem.

During the Munich Crisis of 1938, Admiral Sir Dudley Pound, the commander of the British Mediterranean Fleet, was concerned about the survival of the aircraft carrier HMS Glorious in the face of Italian opposition in the Mediterranean. Pound ordered his staff to re-examine all plans for attacking Taranto. He was advised by the captain of Glorious, Arthur L. St.G. Lyster, that her Fairey TSR Swordfish were capable of a night attack, using aerial torpedoes. Indeed, the Fleet Air Arm was then the only naval aviation arm capable of it. Pound took Lyster's advice, and he ordered training to begin. Security was kept so tight there were no written records. Just a month before the war began, Pound knowingly advised his replacement, Admiral Andrew Cunningham, to consider the possibility. This came to be known as Operation Judgement.

The fall of France and the consequent loss of the French fleet in the Mediterranean (even before Operation Catapult) made redress essential. The older carrier, HMS Eagle, on Cunningham's strength, was ideal, possessing a very experienced air group composed entirely of Swordfish aircraft. Three Sea Gladiators were added for the operation. Firm plans were drawn up after the Italian Army halted at Sidi Barrani, which freed up the British Mediterranean Fleet.

Operation Judgement was just a small part of the overarching Operation MB8. It was originally scheduled to take place on 21 October 1940, Trafalgar Day, but a fire in an auxiliary fuel tank of one Swordfish led to a delay. (The 60 imp gal (270 L; 72 US gal) auxiliary tanks replaced the usual third crewman to extend the operating range of the aircraft enough to reach Taranto.) This minor fire spread into something more serious that destroyed two Swordfish. Eagle then suffered a breakdown in her fuel system, so she was eliminated.

When the brand-new carrier HMS Illustrious, based at Alexandria, became available in the Mediterranean, she took on board five Swordfish from Eagle, and would launch the strike alone.

The complete naval task force, commanded by Rear Admiral Lyster, who had authored the plan of attack on Taranto, consisted of Illustrious, two heavy cruisers, two light cruisers, and four destroyers. The 24 attack Swordfish came from 813, 815, 819, and 824 Naval Air Squadrons. The small number of attacking warplanes raised concern that Judgement would only alert and enrage the Italian Navy without achieving any significant results. Illustrious also had fighters of 806 Naval Air Squadron aboard to provide air cover for the task force.

Half of the Swordfish were armed with torpedoes as the primary strike aircraft, with the other half carrying aerial bombs and flares to carry out diversions. These torpedoes were fitted with Duplex magnetic / contact exploders, which were extremely sensitive to rough seas, as the attacks on the German battleship Bismarck later showed. There were also worries the torpedoes would bottom out in the harbour after being dropped. The loss rate for the bombers was expected to be fifty percent.

Several reconnaissance flights by Martin Maryland bombers (of the RAF's No. 431 General Reconnaissance Flight) flying from Malta confirmed the location of the Italian fleet. These flights produced photos on which the intelligence officer of Illustrious spotted previously unexpected barrage balloons, the attack plan was changed accordingly. To make sure the Italian warships had not sortied, the British also sent over a Short Sunderland flying boat on the night of 11 November, just as the carrier task force was forming up about 170 nmi (200 mi; 310 km) from Taranto harbour, off the Greek island of Cephalonia. This reconnaissance flight alerted the Italian forces in southern Italy, but since they were without any radars, they could do little but wait for whatever came along. The Regia Marina could conceivably have gone to sea in search of any British naval force, but this was distinctly against the naval philosophy of the Italians between January 1940 and September 1943.

The complexity of Operation MB8, with its various forces and convoys, succeeded in deceiving the Italians into thinking only normal convoying was underway. This contributed to the success of Judgement.