'Beta' (i) was an Axis convoy destroyed by British naval forces in the Mediterranean Sea (8/9 November 1941).
Also known as the 'Battle of the Duisburg Convoy', after the largest of the convoy’s ships, the operation resulted from the Axis effort to sail a convoy to Libya with supplies for the Italian army, civilian authorities in Libya, and General Erwin Rommel’s Deutsches Afrika Korps.
The convoy comprised two German merchant vessels (7,889-ton Duisburg and 3,113-ton San Marco), three Italian merchant vessels (6,339-ton Maria, 5,153-ton Sagitta and 5,180-ton Rina Corrado) carrying 389 vehicles, 34,473 tons of munitions and 223 soldiers, and two Italian tankers (5,014-ton Conte di Misurata and 7,599-ton Minatitlan) carrying 17,281 tons of fuel. The convoy’s close escort was commanded by Capitano di Vascello Ugo Bisciani and comprised the destroyers Maestrale, Grecale, Fulmine, Euro, Libeccio and Alfredo Oriani, while the distant covering force was commanded by Ammiraglio di Divisione Bruno Brinovesi and comprised the heavy cruisers Trieste and Trento, and the destroyers Granatiere, Fuciliere, Bersagliere and Alpino.
An 'Ultra' decrypt warned the British that the Axis forces were about to send a convoy to Libya, and the presence of the convoy was confirmed by air reconnaissance before Captain W. G. Agnew’s Force 'K', which comprised the light cruisers Aurora and Penelope, and the destroyers Lance and Lively, departed Malta to effect the desired interception. The British had the advantage of radar, a sensor system which the Italian warships lacked, and surprised the convoy at night. Despite being only 10.5 miles (17 km) away, the Italian distant covering force did not interfere as a result of confusion, firing only some ineffective rounds in the dark.
Force 'K' made 28 kt to the north-east from Malta, with Aurora leading the ships steaming in line-ahead formation, and located the 'Beta' (i) convoy at about 00.00 on 8/9 March about 135 miles (217 km) to the east of Syracuse on the east coast of Sicily. The conditions included modest moonlight to the east, and the British warships took up position with the moon silhouetting the convoy. Agnew was under instructions to attack the nearest escorts first and then fire on the convoy, dealing with the other escorts as they appeared. The British ships slowed to 20 kt and their gun crews were ordered to fire steadily, volume of fire being less important than accuracy. As the British ships closed the convoy, radar detected more ships, assumed to be destroyers and escorts, but in fact the distant escort. Agnew signalled the start of the attack at 00.47, and this signal was received by Trieste, but jamming from Lively prevented any warning from the cruiser from reaching the convoy. Thus the only Italian warships aware of the attack were 11 miles (17 km) distant from the convoy.
Using radar aiming, the British warships opened fire at about 00.58 at a range of 5,200 yards (4745 m) reducing to 3,000 yards (2745 m). Grecale was hit by the first three 6-in (152.4-mm) salvoes from Aurora. The 4-in (101.6-mm) main guns of Lance and of Aurora's secondary armament bombarded a merchant ship. Penelope engaged Maestrale, the leader of the close escort, and was on target with her first salvoes. Lively began to shell the merchant ships three minutes later. The Italians initially believed that they were under air attack, and Maestrale's wireless mast was hit. Fulmine counterattacked, but was soon severely damaged by British fire, Milano losing an arm but remaining in command until the ship sank. Grecale was hit and came to a stop outside torpedo range, and was later towed back to port by Oriani. Remaining undamaged, Euro closed to within 2,200 yards (2010 m) of the British ships but mistook them for Trieste and Trento, an impression fortified by the fact that the ships did not fire on Euro and because Maestrale had been signalling for Italian ships to rally on the far side of the convoy, so Cigala countermanded an order to launch torpedoes. Moments later, the British ships did open fire, but Euro was no longer in a position to undertake a torpedo attack. Six British shells hit Euro, but at a range so short that they passed through the Italian ship without exploding but nonetheless killing about 20 men of the Italian ship’s complement.
The Italian distant escort was on the right-hand side of the convoy, steaming twice as fast and zigzagging to keep station, and also thought that the convoy was under air attack. At 01.13 Brivonesi signalled to the Supermarina naval high command that torpedo bombers were attacking and then steamed not for the British ships' current position but rather for the point at which they had first been sighted. When Trieste's look-outs saw the arc of the British shells and ships beginning to burn, the distant escort was about 5,000 yards (4575 m) distant at the end of its zigzag away from the convoy. As the distant escort closed the convoy, the British ships moved beyond the glare of the fires and became much harder to identify. Trento fired star shells, then both Trieste and Trento opened fire with their 203-mm (8-in) main guns at the British ships at a range of 8,750 yards (8000 m). From 01.10 to 01.25, the British engaged the Axis merchant ships with shellfire and torpedoes, the ships taking little evasive action. The close escort on the eastern side of the convoy moved off with Maestrale and Euro to rally, and then attacked once more, the Italian salvoes having no effect and the ships then being driven away by the fire of the British ships. The distant escort sighted the British again and fired 207 main-armament rounds, managing to straddle some of the British ships. The fires and explosions on the merchant ships obscured the British ships, however, and Brivonesi ordered the distant escort to turn north at 24 kt in an effort to intercept them, but made no further contact. Some shells had landed close to British ships as they finished the destruction of the convoy, but caused only splinter damage to Lively's funnel.
By 01.40 the firing had come to an end.
As dawn broke on 9 November, it became clear that all of the Axis merchant ships had been sunk or were on fire and sinking. The British warships headed at high speed toward Malta at 02.05, chased without success by the Italian covering force, not noticing Italian salvoes at 02.07, and had reached harbour at Malta by 13.00 that afternoon. Force 'K' had sunk about 39,800 tons of Axis shipping. The destroyer Libeccio was torpedoed by the submarine Upholder while rescuing some of the 704 of the convoy’s survivors. Libeccio was taken in tow by Euro but, after suffering an internal structural collapse, sank. The Italian cruisers also searched for survivors and managed to evade torpedoes.
In overall terms, the Axis had lost seven merchant vessels and one destroyer sunk, as well as two destroyers damaged, while the smaller and lighter British force had suffered only light damage to one destroyer. In this catastrophe the Axis forces had also lost 34,473 tons of cargo including fuel, and their deaths totalled 21 civilian, 145 Italian army and 78 German army personnel.
The Italian escort ships of the Axis convoy had lacked co-ordination and made mistakes because of the confusion engendered by mistaken identification, surprise and the very speed of the British attack. They also possessed no answer to the superior British night-fighting equipment and tactics, and technical obsolescence made an Italian attempt to counter the British at night a useless sacrifice of ships and their crews. Additionally, Italian naval morale was seriously degraded by the fact that so formidable an escort had failed to prevent the disaster. On the day after the disaster, Rommel signalled to Berlin that convoys to Italian North Africa has been suspended, and that the vast majority of the men, equipment and fuel needed in Libya had not arrived. Small quantities of supplies arrived in ships sailing alone or in pairs, more journeys were undertaken by submarine, and fuel was carried by warships. Fewer convoys with more escorts and full air cover were planned, and four such convoys sailed on 20 November.
In retrospect it is clear that the Italians had erred in assuming that a night attack by warships was unlikely; the merchant ships should have been instructed to scatter or sail away from an attack; the destroyers on the port side should not have withdrawn but rather attacked at once without regard for the risk of friendly fire; and the distant escort should have estimated the position of Force 'K' instead of heading toward the initial sighting, and then attacked the British as they sailed for Malta. Brivonesi was court-martialled and dismissed for not attacking, but was reinstated on 5 June 1942.
The Germans were outraged by the disaster, and considered the imposition of German naval officers onto the Supermarina and even on Italian ships.
The Supermarina tried to use smaller and more dispersed convoys, sailing at the same time, to mislead the British, but the Allied codebreakers exposed the ruse. When four ships sailed from Naples on 20 November with an escort of heavy and light cruisers, Malta-based British submarines torpedoed two cruisers, forcing the convoy to turn back.