Battle of The Strait of Otranto (1917) - Battle

Battle

By this time, the Allied naval forces in the area were aware of the raid, and were in a position to block the Austro-Hungarian retreat. Rear Admiral Alfredo Acton—the commanding officer of the Italian Scouting Division—ordered Mirabello's group southward at 04:35, while he embarked on the British light cruiser HMS Dartmouth. By 06:45, the cruisers Dartmouth and Bristol—along with the Italian destroyers Mosto, Pilo, Schiaffino, Acerbi, and Aquila—were sailing north in an attempt to cut off the Austro-Hungarian cruisers. The Italian light cruiser Marsala, the flotilla leader Racchia, and the destroyers Insidioso, Indomito, and Impavido were readying to sail in support as well.

The Mirabello group engaged the Austro-Hungarian cruisers at 07:00, but were heavily outgunned, and instead attempted to shadow the fleeing cruisers. At 07:45, Rear Admiral Acton's ships encountered the destroyers Csepel and Balaton. After 20 minutes, the Italian destroyers were able to close the distance to the Austro-Hungarian ships; the two groups engaged in a short artillery duel before a shot from Csepel struck Aquila and disabled the ship's boilers. By this time, the Austro-Hungarian destroyers were under the cover of the coastal batteries at Durazzo, and were able to make good their escape.

At 09:00, Bristol's lookouts spotted the smoke from the Austro-Hungarian cruisers to the south of her position. The Allied ships turned to engage the Austro-Hungarian ships; the British ships had both a superiority in numbers and in firepower; Dartmouth was armed with eight 6 in (150 mm) guns and Bristol had two 6 inch and ten 4 in (100 mm), compared to the nine 3.9 in (99 mm) guns on each of the Austro-Hungarian ships. Unfortunately for the Allies, their numerical superiority was quickly lost, as their destroyers were either occupied with mechanical problems, or protecting those destroyers suffering from breakdowns. The support forces of both sides—the Sankt Georg group for the Austro-Hungarians, and the Marsala group for the Allies—were quickly dispatched to the battle.

Dartmouth—faster than Bristol—closed to effective engagement range with the Austro-Hungarian ships, and opened fire. A shell from Dartmouth struck Novara, at which point the Austro-Hungarian ships laid a smoke screen in order to close the distance. Dartmouth was struck several times, and by 11:00, Acton ordered the ship to reduce speed to allow Bristol to catch up. Novara was hit several more times, and her main feed pumps and starboard auxiliary steam pipe had been damaged, which caused the ship to begin losing speed. At 11:05, Acton turned away in an attempt to separate Saida from Novara and Helgoland. At this point, Sankt Georg was approaching the scene, which prompted Acton to temporarily withdraw to consolidate his forces. This break in the action was enough time for the Austro-Hungarians to save the crippled Novara; Saida took the ship under tow while Helgoland covered them.

Unaware that Novara had been disabled, and fearing that his ships would be drawn too close to the Austrian naval base at Cattaro, Acton broke off the pursuit. The destroyer Acerbi misread the signal, and attempted to launch a torpedo attack, but was driven off by the combined fire of the Novara, Saida, and Helgoland. At 12:05, Acton realized the dire situation Novara was in, but by this time, the Sankt Georg group was too close. The Sankt Georg group rendezvoused with Novara, Saida, and Helgoland, and Csepel and Balaton reached the scene as well. The entire group returned to Cattaro together.

At 13:30, the submarine UC-25 torpedoed Dartmouth, causing serious damage. The escorting destroyers forced UC-25 from the area, but Dartmouth had to be abandoned for a period of time, before it could be towed back to port. The French destroyer Boutefeu attempted to pursue the German submarine, but struck a mine laid by UC-25 that morning and sank rapidly.