Roon class Armoured Cruisers

German Empire (1901): SMS Roon, Yorck

The Roon class: Standard confirmed

The Roon class were follow-up armored cruisers of the Prinz Adalbert-class, built for the Kaiserliche Marine. Although quite similar in general appearance, they still incorporated incremental improvements, notably for the powerplant, reflected in their fourth funnel. Still, they had a relatively light armament and thin protection compared to the foreign armoured cruisers, notably those of the British Royal Navy of the time, the Devonshire class for example (1902) had four single BL 7.5-inch (191 mm) Mk I guns, while the Duke of Edinburgh class (1904) had no less than six BL 9.2-inch (234 mm) Mk X guns, for 12,590 long tons (12,790 t) versus 10,260. They ended not as fast as expected, but still two knots faster than the previous cruisers.



Roon and Yorck served in the 1st Scouting Group, the reconnaissance force of the Hochseeflotte when starting their service, used as group and deputy commander flagships. As battlecruisers started to replace them, they were decommissioned in 1911 and 1913 respectively, but reactivated in emergency in August 191 and assigned to III Scouting Group with the same duty as before and Roon as the group flagship, so that they operated together again. In November 1914 they participated in the raid on Yarmouth, but Yorck was lost in a minefield at her return. The group was disbanded and Roon was transferred to the Baltic in April 1915. She took part notably in the attack on Libau in May, Battle of the Åland Islands in July, Battle of the Gulf of Riga in August and decommissioned in 1916. She was used as training ship and later, accommodation vessel at anchor. She could have been converted into a seaplane tender but after 1918 she was stricken and BU in 1921.

Design of the Roon class

Hull & protection

The Roon class hull was 127.30 meters (417 ft 8 in) long at the waterline, and 127.80 m (419 ft 3 in) overall. The beam was 20.20 m (66 ft 3 in) at the largest frame, while they had a draft of 7.76 m (25 ft 6 in), for a total displacement between 9,533 metric tons (9,382 long tons) (normal) and 10,266 metric tons (10,104 long tons) fully loaded. So in short they were slightly longer, slightly thinner and with less draft and less tonnage than the Prinz Adalbert, and two more boilers were supposed to give them a great speed boost all combined: 22 knots instead of 19. This proved too optimistic. The hull's construction called for transverse and longitudinal steel frames with steel hull plates riveted on as previous cruisers. Below the armoured deck were managed twelve watertight compartments, with a double bottom below, running for 60% of the tota lenght.

SMS Roon and Yorck had Krupp cemented steel armor and on the waterline they had an armored belt 100 mm (3.9 in) thick (amidships) betwene barbettes, so around the vitals. It decreased down to 80 mm (3.1 in) on both ends of the central section. This armoured belt was backed by a layer ot teak, 55 mm (2.2 in) thick, acting as buffer. The casemate deck was protected by side armor 100 mm thick. The armored deck was 40 mm up to 60 mm (1.6–2.4 in), connected to the belt using sloped armor 40–50 mm (1.6–2.0 in) thick. The forward conning tower walls were 150 mm (5.9 in) on thickness with a 30 mm (1.2 in) roof. The rear conning tower was, as usual also, thinner, with 80 mm walls, 20 mm (0.79 in) roof. The main battery gun turrets frontal arc was protected by 150 mm thick plates and 30 mm roofs. The secondary (15 cm) turrets had 100 mm thick front and sides, 80 mm gun shields. Main Barbettes were about 150 mm, secondary 80 mm.

This armour scheme was in no way revolutionary, it ticked all the boxes of previous ships, going down to SMS Prinz Heinrich, but still was way less than the Prinz Adalbert class. The reason of this decrease was the same as two more boilers and a thinner beam, draft and tonnage: Achieving a better speed. But this was quite a price to pay for two more knots only usable when the sea calm.

Powerplant & mobility

Powerplant arrangement SMS Roon and Yorck had basically the same engine arangement as the Prinz Adalbert, using three 3-cylinder vertical triple expansion engines(VTE), driving each a screw propeller. The central propeller was 4.50 m (14 ft 9 in) in diameter, while the outer ones were 4.80 m (15 ft 9 in). The central one could be use for cruising, the outer for high speed manoeuvers. The only real change was the use of sixteen Düsseldorf-Ratinger Röhrenkesselfabrik (Dürr) coal-fired water-tube boilers, instead of 14, so two more. Each had 4 fireboxes, making for a grand total of 48. These boilers were ducted into not three, but four funnels, making the easiest dinstinction between the Roon and Prinz Adalbet class. This ensemble produced together 19,000 ihp (14,200 kW), allowing for a top speed of 22 knots (41 km/h).

At sea
On trials, none proved able to reach this designed and contracted speed. Roon managed to reached 21.1 knots (39.1 km/h; 24.3 mph) and Yorck 20.4 knots (37.8 km/h; 23.5 mph). For electrical outfitting, both cruisers called for four turbo generators in all, producing a total of 260 kilowatts/110 volts. Like the previous cruisers however, the Roon class proved to be good sea boats. Even fully loaded they had a gentle motion and manoeuvred well, responsive to the helm, despite a single rudder steering. Hard over however they heeled and lost 60% speed. They were stable, with their metacentric height of 1.04 m (3 ft 5 in). Their range was 4,200 nmi (7,800 km; 4,800 mi) at 12 knots (22 km/h; 14 mph), less than the Prinz Adalbert class. Complement was 35 officers, and 598 enlisted sailors and as squadron flagship, they had accommodations for extra 13 officers and 62 personal. A second command ship it was 9 officers, 44 personal.

Armament

Main Battery:
Primary armament comprised four 21-centimeter (8.3 in) SK L/40 guns (40 caliber), mounted in two twin-gun turrets fore and one aft. Turrets of the DrL C/01 type had hydraulical power. Elevation ranged from -5 to +30 degrees. They fired a 108 kg (238 lb) AP (armor-piercing) shell at a muzzle velocity of 780 meters per second (2,600 ft/s). Maximum range for the SK L/40 was 16,200 m (17,700 yd). They also had a complement of HE (High explosive) shells, and that could depend on the mission. In total, 380 shells were carried.

Secondary battery:
It comprised ten 15 cm (5.9 in) SK L/40 guns, all in single turrets, and clustered casemates amidships. This was two less than the previous Prinz Adalbert. They fired a 40 kg (88 lb) shell at 800 m/s (2,600 ft/s). They could be elevated also to 30%, providing a maximum range of 13,900 m (15,200 yd). However these casemates were placed way too low: As a result, they were always "wet" in heavy seas. To the point heavy spray prevented their use altogether. In all, 1,600 6-inches rounds were carried.

Tertiary Battery:
For close-range defense they counted on fourteen 8.8 cm SK L/35 guns. This was four more than the previous Prinz Adalbert, but the Roon were larger. They were all placed individual casemates along the upper superstructure, pivot mounts on upper decks. These guns fired a 7 kg (15 lb) shell at 770 m/s (2,500 ft/s). At max elevation (25 degrees) they reached a 9,100 m (10,000 yd) range. 2,100 shells were stored for these guns.

Torpedo Tubes:
Like previous cruisers, the Roon class was equipped with four 45 cm (17.7 in) torpedo tubes, submerged, in the bow, stern, and broadside, creating a lozenge. This was two less than the previous Prinz Adalbert. These were capable of launching the standard C/03 torpedo, which was fitted with a 147.5 kg (325 lb) warhead. The standard range gad two setups:
-1,500 m (4,900 ft) at 31 knots (57 km/h; 36 mph)
-3,000 m (9,800 ft) at 26 knots (48 km/h; 30 mph)

Ship's construction & commission

SMS Roon was ordered as "Ersatz Kaiser" a provisional name as a replacement for the ironclad Kaiser. The contact went to Imperial Dockyard in Kiel. Construction number was 28. She was laid down on 1 August 1902 and launched on 27 June 1903 with a ceremony held by Field Marshal Alfred von Waldersee. The new cruiser was named after Field Marshal Albrecht von Roon. The Fitting-out commenced as well as provisions for a flagship use, until she was commissioned on 5 April 1906 under command of Kapitän zur See Fritz Hoffmann. Her name com from the prussian officer and statesman Albrecht von Roon, 1st minister of war of a unified German Empire in the 1870s.

SMS Yorck on her part was ordered as "Ersatz Deutschland", built at Blohm & Voss in Hamburg. Her construction number was 167. She was laid down on 25 April 1903, launched on 14 May 1904, a ceremony presided by General Wilhelm von Hahnke which gave a speech. She was christened after Ludwig Yorck von Wartenburg, a Prussian general during the Napoleonic Wars. The bottle was launched by Josephine Yorck von Wartenburg, a descendant of Ludwig. Fitting-out work was completed by late 1905 and she started her first builder's trials, then the shipyard crew transferred the vessel to Kiel for the commission ceremony on 21 November.

Roon as a seaplane carrier (1918)

The German Navy experimented with seaplane carriers, notably converted the old light cruiser SMS Stuttgart in early 1918. But since she could carry only two aircraft, insufficient and efficient air cover and support, plans were drawn up to convert the much larger Roon into a seaplane carrier herself. The conversion would have seen the addition of a large hangar and facilities to operate four reconnaissance seaplanes. Her main battery deposed and replaced with six lighter 15 cm guns, six 8.8 cm AA guns; The hangar was to be installed aft of the main superstructure. The plan never traduced into a conversion, since in between, the German Navy found zeppelins could provide an equally long range, long duration aerial reconnaissance.


Old author's Profile of Roon

Roon Specifications
Dimensions	127.8 x 20.2 x 7.76 m (419 oa x 66 x 25 ft)
Displacement	9,533 t standard, 10,226 FL
Crew	35 officers, 598 ratings
Propulsion	3 shafts, 14 boilers, 3 VTE engines 19,000 ihp (14,000 kW)
Speed	21 knots (39 km/h; 24 mph), Range: 4,200 nmi/12 knots
Armament	2x2 21 cm (8.2 in), 10 × 15 cm (5.9 in), 14 × 8.8 cm (3.5 in) SK L/30, 4 × 45 cm (18 in) TTs
Armor	Belt: 150 cm (7.9 in), Turrets: 20 cm (7.9 in), Deck: 3 cm (1.2 in)

Read More:

J. Gardiner Conway's all the world's fighting ships 1865-1905
Dodson, Aidan (2016). The Kaiser's Battlefleet: German Capital Ships 1871–1918. Barnsley: Seaforth Publishing.
Friedman, Norman (2011). Naval Weapons of World War One: Guns, Torpedoes, Mines and ASW Weapons of All Nations; An Illustrated Directory.
Gardiner, Robert, ed. (1979). Conway's All the World's Fighting Ships 1860–1905. Conway.
Gardiner, Robert & Gray, Randal, eds. (1985). Conway's All the World's Fighting Ships: 1906–1921.
Greger, Rene (1964). "German Seaplane and Aircraft Carriers in Both World Wars". Warship International. Toledo: Naval Records Club, Inc. I (1–12)
Grießmer, Axel (1999). Die Linienschiffe der Kaiserlichen Marine: 1906–1918; Konstruktionen zwischen Rüstungskonkurrenz und Flottengesetz, Bonn: Bernard & Graefe Verlag.
Gröner, Erich (1990). German Warships: 1815–1945. I: Major Surface Vessels. Annapolis: Naval Institute Press.
Herwig, Holger (1998) [1980]. "Luxury" Fleet: The Imperial German Navy 1888–1918. Amherst: Humanity Books.
Hildebrand, Hans H.; Röhr, Albert & Steinmetz, Hans-Otto (1993). Die Deutschen Kriegsschiffe (Band 7/8) (in German).
Massie, Robert K. (2003). Castles of Steel. New York City: Ballantine Books.
Pavlovich, Nikolaĭ Bronislavovich (1979). The Fleet in the First World War: Operations of the Russian Fleet. New Delhi: Amerind Pub. Co.
Scheer, Reinhard (1920). Germany's High Seas Fleet in the World War. London: Cassell and Company, ltd.
Staff, Gary (2006). German Battlecruisers: 1914–1918. Oxford: Osprey Books.
Taylor, John (1970). German Warships of World War I. Garden City: Doubleday.
Tucker, Spencer E. (2005). The Encyclopedia of World War I. ABC-CLIO.
//en.wikipedia.org/wiki/Roon-class_cruiser

The Roon class in service

SMS Roon

Prewar routine

Roon had her began sea trials lasting until 9 July after which she joined I Scouting Group (15 August). She replaced SMS Friedrich Carl as flagship, deputy commander Kommodore Raimund Winkler. She participated in the annual fleet maneuvers this summer, the one of many until the war. Hoffmann was replaced by Fregattenkapitän Oskar von Platen-Hallermund, relieved in turn by KzS Karl Zimmermann. Winkler was replaced by Kommodore Eugen Kalau vom Hofe.


SMS Brandenburg and Roon in 1906

Roon training exercises and cruises went on without incident in 1905, 1906 and 1907 with the I Scouting Group and High Seas Fleet on some ocasions. By early 1907 however she sailed for United States taking part in the Jamestown Exposition, a commemoration of the arrival of the first pilgrims in America in Chesapeake Bay. Roon led the German delegation, flaned by the cruiser Bremen. Both had previously departed Kiel on 8 April, crossed the Atlantic to Hampton Roads, arriving the 24, taking part in the multinational naval review. Bremen remained on station but Roon returned to Germany, arriving on 17 May.

By September-October 1907, Roon was again deputy flagship as Yorck was overhauled and FK Friedrich Schrader took command. She went on a major cruise into the Atlantic (7-28 February 1908) with the scouting group. For the first time she used her wireless telegraphy at long distances. On her way back she stopped in Vigo for coaling. On 5 March she was back to flagship duty (Konteradmiral Kalau von Hofe). She made another Atlantic cruise thus summer with the battleship squadrons. Fleet commander Prince Heinrich indeed pressed for this coordinating cruise amidst growing tension with UK and naval arms race. The goal was to prepare the fleet for overseas operations out of German waters. The fleet sailed on 17 July, and was back on 13 August. Autumn maneuvers followed until 12 September. KAdm Jacobsen became the new commander, while FK Georg Scheidt took command.


SMS Roon photographed during an USN visit in 1907

In 1909 Roon made a first atlantic cruise in February with her Scouting Group and the summer one with the Hochseeflotte. On her way back she stopped in Spithead. KzS Reinhard Koch relieved Jacobsen after the fleet maneuvers of September 1909. 1910-11 reproduced that same routine but she took part in a naval review for Kaiser Wilhelm II in September 1911. Afterwards, she was decommissioned on 22 September 1911, no longer active in 1912-14.

World War I

Reactivated in July 1914 and fully recommissioned on 2 August she joined the II Scouting Group as the flagship (Captain KzS Johannes von Karpf). Soon she joined the IV Scouting Group, replacing Blücher. On 25 August her group was renamed III Scouting Group. KAdm Hubert von Rebeur-Paschwitz became the new group commander. Their first sortie was in the eastern Baltic, trying to rescue the stranded Magdeburg, but she was recalled as the latter was scuttled to avoid capture. Next, she was deployed in late September to the Skagerrak was after false reports of a signalled British squadron. Next she escorted the Nautilus and Albatross and the auxiliary minelayer Kaiser. They would lay the large "Alpha" defensive minefield of the North Sea. She was also detached top escort the High Seas Fleet's raid on Yarmouth on 2–3 November 1914.

Roon with the Hochseeflotte

On 15–16 December, she covered the raid on Scarborough, Hartlepool and Whitby. She sailed with SMS Prinz Heinrich, with the van of the High Seas Fleet's battlecruisers. Roon and her attached destroyers spitted a British screening force and the destroyers HMS Lynx and Unity forward. But no fire was exchanged and the two forces broke off. Reports from Roon and Hamburg were intercepted by the British and Admiral von Ingenohl ordered to disengage and head back for Germany. Roon and her escort destroyers acted as rearguard, now joined by the Stuttgart and Hamburg,. The latter encountered Commander Loftus Jones' destroyers. Jones later shadowed Roon for about 45 minutes, before being chased off by Stuttgart and Hamburg, later odered back. Meanwhile the battlecruiser HMS New Zealand was detached to hunt them down, three more battlecruisers behind. They later brok off.

Operations in the Baltic

The III Scouting Group's crusiers at that time were judged too slow and weak to take part in north sea operations. The general staff wanted them eastwards, to act against the Russian Baltic fleet. On 15 April 1915, III Scouting Group departed, but the units was dissolved, all ships joining KAdm Albert Hopman's Reconnaissance Forces of the Baltic. FK Hans Gygas replaced Karpf, now deputy commander. On 30 April Roon came back home in drydock in Kiel for a well deserved overhaul. She was back in May for the attack on Libau. On their way she and other ships were ambushed by British submarine E9, which fired five torpedoes but missed. Roon would make four sorties, one even at Gotska Sandön in May and June. Hopman raised his mark on Roon as SMS Prinz Adalbert was under repairs after a torpedo hit.

Roon and Lübeck then covered a minelaying operation on 30 June-2 July. They were catch by the Russian squadron at the Battle of Åland Islands. SMS Augsburg and three destroyers, closest to the Albatross were spoted and attacked by Bayan, Admiral Makarov, Bogatyr and Oleg. Augsburg escaped and the destroyers were hard-pressed covering Albatross, severely damaged. Roon joined Lübeck and soon spotted and engaged Bayan while Lübeck fired on Oleg. Eventually the much more powerful armoured cruiser Rurik arrived to turn the tables, hitting Roon until the Germans broke off.



July 1915 saw a German Army push further north from Libau and naval forces were to cover them, reincoforced by the pre-dreadnoughts of the IV Battle Squadron. Vizeadmiral Ehrhard Schmidt took overall command. In August, this fleet was in the Gulf of Riga, followed by a naval battle until reports of British submarines on 20 August had the Germans packing. Roon was just in distant cover, but later on 10 August with Prinz Heinrich she shelled Russian positions at Zerel (Sworbe Peninsula), putting abalaze several Russian destroyers anchored there.

On 9 September, Hopman raised his mark on Prinz Adalbert again, Roon returing to Kiel for a drydock overhaul. By mid-October she was back to Libau, becming flagship again. However after the loss of Prinz Adalbert to a British submarine, the German High Command decided than older cruiser with poor ASW protection would be retired. Roon departed on 15 January 1916 to Kiel, to be decommissioned on 4 February. By November the same year she was disarmed, converted into astationary training/accommodation ship in Kiel. In early 1918, proposition was made to convert her to a seaplane carrier, but this never was carried out. She was stricken in 1920 and BU next year.

SMS Yorck

Prewar routine

After commissioning, SMS Yorck was sent to the same I Scouting Group as her sister ship, on 27 March 1906. On 2 April 1906, she replaced Friedrich Carl as group flagship (Vizeadmiral Gustav Schmidt). The peacetime routine of the 1907-1913 comprised training exercises with the fleet reconnaissance forces and in conjunction with the High Seas Fleet, notably during the summer in the Atlantic as conditions were better; On 29 September, Konteradmiral Hugo von Pohl became group commander. Yorck went into drydock in 1907, until 28 October for overhault. Meanwhile, KAdm August von Heeringen became the new flagship commander, raising his mark on Yorck, making an Atlantic Ocean drill until 28 February 1908, making tactical exercises and experimented with their wireless telegraphy. On 1st May SMS Scharnhorst became the new group flagship.


Yorck through the Kiel Canal

Another Atlantic cruise followed. Yorck stopped in Funchal (Madeira Is.) and Coruña in Spain and was back home on 13 August. Autumn maneuvers followed until 12 September and the was awarded the Kaiser's Shooting Prize for marksmanship among all other armored cruisers for 1907–1908. Erich Raeder became her ship's navigation officer. Kpt. Arthur Tapken took command until September 1909. In February 1909, I Scouting Group made anoher atantic crusier and Yorck stopped in Vigo. As Scharnhorst was detached to the East Asia Squadron on 11 March, Yorck was flagship again. After another cruiser in July and August, Yorck stopped at Vilagarcía de Arousa and later Spithead. In early 1910 Blücher became flagship (VAdm Heeringen) on 27 April. Yorck became deputy commader flagship (KAdm Reinhard Koch) replaced by KAdm Gustav Bachmann, and KAdm Maximilian von Spee, on 15 September. Bachmann became group commander. Yorck won a new Schießpreis in 1909–1910, under command of Ludwig von Reuter from September.


SMS Yorck's stern

She underwent shipyard's maintenance but on 31 March 1911, a benzene explosion killed on and injured 4 sailors. Repaired, she saw Franz von Hipper replacing Spee, and the joined her crew to Norway and Sweden. She visited Uddevalla, but did not took part in the unit maneuvers of February 1912. With four light cruisers she was detached to I Scouting Group. In September Fregattenkapitän Max Köthner replaced Reuter while she saw one of her pinnaces accidentally detonating a naval mine. On 4 March 1913 off Helgoland she cut in two the torpedo boat S178 while attempting to pass in front of her but misjudged the distance. With Oldenburg, and S177 she pulled out 15 men from the sea. Slightly damaged she went on with the maneuvers. Bachmann alternated with Funke. Later detached to Kiel, Yorck was decommissioned on 21 May, underwent an overhaul and joined the in reserve.

World War I

Yorck was mobilized in July and and recommissioned on 12 August (Captain KzS Pieper) with a brand new crew (her former crew went with the Seydlitz). IV Scouting Group on 25 August, she joined the III Scouting Group (KAdm Hubert von Rebeur-Paschwitz). On 20 September, she patrolled the German Bight, and was transferred to the Baltic Sea, heading as far north as Östergarn until 29 September, before returning to the North Sea. She joined the Hochseeflotte, and on 3 November, participated in the raid on Yarmouth, as distant support in case of a British counterattack (which was the goal). Yorck provided also a reconnaissance screen. The squadron went back to Wilhelmshaven when encountering heavy fog, while just appeaoching defensive minefields outside Kiel. The ships provisionally anchored in the Schillig roadstead.

KzS Pieper, believed the fog was now sufficiently cleared so he ordered Yorck's departure. The pilot however refused to take responsibility for maneuvering the crusier, known full well about the minefields nearby, and at 04:10, Yorck struck a mine. As she started to turn to exit the minefield, she stroke another one. The damage was such that it is estimated the crew barely had time to escape. She sank in minutes, with heavy loss of life. Naval historians are still unsure of the tolly. Pieper was tried in a court-martial afterwards and sentenced to two years' imprisonment. The wreck was initially marked and from 1926, partially scrapped. This was completed on 1936–1937. What was left was retired in 1983.

Naval History