SMS Rostock

SMS Rostock was a light cruiser of the Karlsruhe-class cruiser built by the German Kaiserliche Marine (Imperial Navy). She had one sister ship, SMS Karlsruhe; the ships were very similar to the previous Magdeburg-class cruisers. The ship was laid down in 1911, launched in November 1912, and completed by February 1914. Armed with twelve 10.5 cm SK L/45 guns, Rostock had a top speed of 28.5 kn and displaced 6191 t at full load.

Rostock served with the High Seas Fleet as a leader of torpedo boat flotillas for the duration of her career. She served with the screens for both the battlecruisers of the I Scouting Group on operations against the British coast and the Battle of Dogger Bank. She was assigned to the screen for the battle fleet during the Battle of Jutland on 31 May – 1 June 1916. She saw major action at Jutland and frequently engaged British light forces, culminating in her torpedoing by destroyers shortly after midnight. She was taken under tow by German torpedo boats, but the following morning the cruiser HMS Dublin (1912) came upon the retreating ships. The Germans set scuttling charges aboard Rostock and took off the crew before Dublin arrived on the scene.

Construction
Rostock was ordered under the contract name "Ersatz SMS Geier" and was laid down at the Howaldtswerke shipyard in Kiel in 1911. She was launched on 12 November 1912; at her launching, she was christened by the mayor of Rostock, Dr. Magnus Maßmann. After completing Fitting-out work, the ship was commissioned into the High Seas Fleet on 5 February 1914. The ship was 142.2 m long overall and had a beam of 13.7 m and a draft of 5.38 m forward. She displaced 6191 t at full combat load. Her propulsion system consisted of two sets of Marine steam turbines driving two 3.5 m propellers. They were designed to give 26000 shp, but reached 43628 shp in service. These were powered by twelve coal-fired Marine-type water-tube boilers and two oil-fired double-ended boilers. These gave the ship a top speed of 29.3 kn. Rostock carried 1300 t of coal, and an additional 200 t of oil that gave her a range of approximately 5000 nmi at 12 kn. Rostock had a crew of 18 officers and 355 enlisted men.

The ship was armed with twelve 10.5 cm SK L/45 guns in single pedestal mounts. Two were placed side by side forward on the forecastle, eight were located amidships, four on either side, and two were side by side aft. The guns had a maximum elevation of 30 degrees, which allowed them to engage targets out to 12700 m. They were supplied with 1,800 rounds of ammunition, for 150 shells per gun. She was also equipped with a pair of 50 cm torpedo tubes with five torpedoes submerged in the hull on the broadside. She could also carry 120 mines. The ship was protected by a waterline armored belt that was 60 mm thick amidships. The conning tower had 100 mm thick sides, and the deck was covered with up to 60 mm thick armor plate.

Service history
Following her commissioning in February 1914, Rostock was assigned as a torpedo boat flotilla leader with the High Seas Fleet. On 24 January, 1915, Rostock formed part of the support for Admiral Franz von Hipper battlecruisers in the I Scouting Group during a sortie to destroy British light forces known to be operating near the Dogger Bank. The ship steamed with three other light cruisers and nineteen torpedo boats. Rostock and several of the torpedo boats were tasked with screening the port flank of the battlecruiser squadron. The German group encountered five British battlecruisers, resulting in the Battle of Dogger Bank, during which the armored cruiser SMS Blücher was sunk. Rostock participated in the bombardment of Yarmouth and Lowestoft on 24 April 1916, and as part of the screen for the I Scouting Group. While the battlecruisers bombarded Lowestoft, Rostock and five other cruisers engaged the Harwich Force. Shortly thereafter, the battlecruisers intervened and forced the Harwich Force to withdraw. The German squadron then broke off and returned to port.

Rostock also participated in the Battle of Jutland, on 31 May 1916. She served as the leader of the torpedo boat flotillas, flying the flag of Kommodore Andreas Michelsen. The flotilla was tasked with screening for the battle squadrons of the High Seas Fleet. As the German fleet reached the engagement between the British and German battlecruiser squadrons at 17:30, a pair of destroyers, HMS Nestor (1915) and HMS Nicator attempted to attack the German battle line. Rostock and a number of the battleships engaged the destroyers, which were both disabled by the heavy German fire. The battleships destroyed Nestor and Nicator and their crews were picked up by German torpedo boats.

At 19:32, Rostock and several torpedo boats crossed through the German line and began to lay a smoke screen to cover the withdrawal of the German fleet. Some twenty minutes later, Michelsen detached several torpedo boats to assist the badly damaged battlecruiser SMS Lützow. By the time the German fleet had assumed its night cruising formation, Rostock fell in with the light cruisers of the IV Scouting Group on the port side of the fleet. Shortly before midnight, Rostock and the IV Scouting Group came into contact with the 2nd Light Cruiser Squadron. Shortly after midnight, the British 4th Destroyer Flotilla attacked the German line, where Rostock was positioned. She joined the cannonade directed against the destroyers as they pressed home their attack. The destroyers launched several torpedoes at the Germans, forcing Rostock and the other cruisers to turn away to avoid them; this pointed the ships directly at the battleships in the I Battle Squadron. Rostock successfully passed through the formation, but the cruiser SMS Elbing was rammed by one of the battleships and disabled.

In the chaos of the night engagement, Rostock's search lights illuminated the destroyer HMS Broke (1914). Gunfire from Rostock and the battleships SMS Westfalen and SMS Rheinland smothered the British destroyer; although heavily damaged, she managed to limp back to port. The ship was attacked by the destroyers HMS Ambuscade and Contact; the two ships each fired a single torpedo at high-speed settings at a range of about 1000 yd. One torpedo struck Rostock at 1:30, though it is unknown which destroyer launched it. Rostock was also hit by three 4 in shells, probably from the destroyer Broke. The disabled Rostock called the destroyer S54 to join her; S54 took Rostock in tow, at times making up to 10 kn. The pair was subsequently joined by the destroyers V71 and V73, which had been detached from the flotilla to escort Rostock back to port.

At around 03:55 on 1 June, the four German ships encountered the British cruiser HMS Dublin (1912). The three destroyers went alongside the crippled cruiser and evacuated her crew, while flashing the first two letters of the British signal challenge. Smoke screens were laid to obscure the identity of the German warships. After about ten minutes, S54 departed with Rostock's crew aboard, while V71 and V73 remained. Scuttling charges had been set in the cruiser, but to ensure Rostock sank faster, the two destroyers fired a total of three torpedoes into the ship. Rostock sank bow-first at approximately 04:25, after which V71 and V73 made for Horns Reef at high speed. Of Rostock's crew, 14 men were killed and 6 were wounded during the battle. In the course of the battle, Rostock fired some 500 rounds of 10.5 cm ammunition, more than any other German ship. A second Rostock, of the Cöln-class cruiser, was launched in April 1918, but was not completed before the end of the war.