SMS S143

SMS S143 was a S138-class large torpedo boat of the Imperial German Navy. The S138-class were large torpedo boats that were required to reach a speed of 30 kn and armed with three 45 cm (17.7 in) torpedo tubes. S143 was built by the Schichau-Werke at Elbing and was launched on 6 April 1907, entering service later the same year.

S143 was sunk by a boiler explosion on 4 August 1914, shortly after the start of the First World War, but was raised, repaired and returned to service. S143 served in the Baltic Sea for the rest of the war, and was renamed T143 in 1917. She took part in Operation Albion, the German invasion and occupation of the West Estonian Archipelago in October 1917, and in the German invasion of the Åland islands in 1918.

T143 continued to serve in postwar Weimar Germany's Reichsmarine, and was stricken in 1927 and scrapped in 1930.

Design and construction
The Imperial German Navy ordered 12 large torpedo boats (Große Torpedoboote) from Schichau-Werke as part of the fiscal year 1906 shipbuilding programme. This 12-ship order, sufficient to equip an entire torpedo-boat flotilla, was a result of a planned increase in the size of the German torpedo forces from 96 to 144 torpedo boats under the 1906 Amendment to the 1900 Naval Act. The 1906 torpedo boats were of similar size and armament to SMS G137, the turbine-engined torpedo boat that was the last of the 1905 programme, and were required to reach a speed of 30 kn.

S143 was 70.7 m long overall and 70.2 m between perpendiculars, with a beam of 7.8 m and a draught of 2.75 m. The ship had a design displacement of 533 t which increased to 684 t at deep load. Four coal-fired water-tube boilers fed steam at a pressure of 19.5 atm to 2 three-cylinder triple expansion engines with a total of 11000 ihp. This allowed speeds of 30.3 kn to be reached during Sea trials. The ships bunkers had a capacity of 194 t, while a further 20 t could be carried on deck. This gave a range of 1830 nmi at 17 kn and 390 nmi at 24 kn.

S143's as-built armament was a single 8.8 cm SL L/35 gun (with 100 shells) and three 5.2 cm L/55 guns (with 150 shells per gun). Three single 45 cm (17.7 in) torpedo tubes were fitted, with a single spare torpedo carried. She was later re-armed, with a second 8.8 cm L/35 gun replacing two of the 5.2 cm guns. The ship had a crew of 3 officers and 77 other ranks, which increased to 93 when being used as a flotilla leader.

S143 was laid down at Schichau's Elbing, Prussia (now Elbląg, Poland) shipyard as yard number 782, was launched on 6 April 1907 and was completed on 12 October 1907.

Service
In 1908, S143 was listed as part of the 4rd torpedo boat half-flotilla, part of the Training Flotilla (Schul-Flottille). In 1909, S143 had moved to the 1st half-flotilla, part of the 1st Training Flotilla. In 1910, S143 was still part of the 1st half-flotilla which was now part of the active duty 2st Torpedo boat Flotilla, continuing to serve with the same formation into 1911. In 1913, she was listed as leader of the 3rd half flotila of the 2nd Torpedo boat Flotilla, remaining in that role in 1914.

First World War
On 4 August 1914, the same day that Britain declared war on Germany, S143 suffered a boiler explosion and sank in the western Baltic sea near Gjedser. Twenty men were killed, and S143 sank. The torpedo boat was raised, however, repaired and returned to service. On 23 October 1915, S143 and sister ship SMS S143 were escorting the armoured cruiser SMS Prinz Adalbert (1901), which had set out from Libau (now Liepāja, Latvia) to carry out a patrol between Fårö and Dagerort, when the British submarine HMS E8 torpedoed Prinz Adalbert. One of Prinz Adalbert's ammunition magazines exploded, sinking the cruiser. There were only three survivors, which were picked up by S142 and S143, with 672 killed. This was the biggest loss of life during the war for the German Navy in the Baltic. The two torpedo boats did not see any torpedo tracks, and it was believed at the time that Prinz Adalbert had been sunk by a mine.

On 2/3 May 1916, S143 took part in a minelaying operation in the Gulf of Finland, part of a minesweeping screen ahead of the minelayer SMS Deutschland (1914). The next day, S143 and SMS S175 struck the submerged wrecks of sunken merchant ships at the entrance to Libau harbour, and were both damaged sufficiently to require repair at a dockyard. S143 was renamed T143 on 24 September 1917, in order to release her name for new construction, in this case SMS V143, a 1916 Mobilisation Type torpedo boat which although launched in 1918, was never completed. T143, now part of the 7th torpedo-boat half-flotilla, took part in Operation Albion, the German invasion and occupation of the West Estonian Archipelago in October 1917. On 7 March 1918, T143 took part in German landings in the Åland islands. T143 remained part of the 7th half-flotilla, part of the 4th Torpedo Boat Flotilla, at the end of the war.

Weimar Republic
After the end of the war, T143 was retained by the Weimar Republic's navy, the Reichsmarine, and when the Treaty of Versailles limited Germany's torpedo forces to 12 destroyers and 12 torpedo boats in active service, with a further 4 of each type in reserve, T139 was retained as an active torpedo boat. T143 was modified with a larger bridge and funnel caps fitted while being refitted for Reichsmarine service, while the 8.8 cm guns were replaced by more powerful 8.8 cm SK L/45 naval guns. The construction of the new Type 23 and Type 24 torpedo boats allowed the older vessels to be phased out, and S143 was stricken on 10 May 1927, and sold for scrap on 25 March 1930.