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SM U-21

1st September 1914 U-Boat Index - WW1  SM U-21

Type U 19 Shipyard Kaiserliche Werft, Danzig (Werk 15) Ordered 25 Nov 1910 Laid down 27 Oct 1911 Launched 8 Feb 1913 Commissioned 22 Oct 1913.
22 Oct 1913 - 31 Aug 1918 Otto Hersing 1 Sep 1918 - 11 Nov 1918 Friedrich Klein

Career 11 patrols.
start date unknown - 4 Mar 1917 Pola Flotilla.
1 Aug 1914 - 5 Jun 1915 III Flotilla.
5 Jun 1915 - end date unknown Constantinople Flotilla.
4 Mar 1917 - 11 Nov 1918 III Flotilla.

Successes 36 ships sunk with a total of 79,005 tons.
2 ships damaged with a total of 8,918 tons.
4 warships sunk with a total of 34,575 tons.

  • 5 Sep 1914 U 21 Otto Hersing Pathfinder (hms) 2,940 br
  • 23 Nov 1914 U 21 Otto Hersing Malachite 718 br
  • 26 Nov 1914 U 21 Otto Hersing Primo 1,366 br
  • 30 Jan 1915 U 21 Otto Hersing Ben Cruachan 3,092 br
  • 30 Jan 1915 U 21 Otto Hersing Kilcoan 456 br
  • 30 Jan 1915 U 21 Otto Hersing Linda Blanche 369 br
  • 25 May 1915 U 21 Otto Hersing Triumph (hms) 11,985 br
  • 27 May 1915 U 21 Otto Hersing Majestic (hms) 14,900 br
  • 4 Jul 1915 U 21 Otto Hersing Carthage 5,601 fr
  • 1 Feb 1916 U 21 Otto Hersing Belle Of France 3,876 br
  • 8 Feb 1916 U 21 Otto Hersing Admiral Charner 4,750 fr
  • 30 Apr 1916 U 21 Otto Hersing City Of Lucknow 3,669 br
  • 26 Oct 1916 U 21 Otto Hersing Marina G. 154 it
  • 28 Oct 1916 U 21 Otto Hersing Gilda R. 37 it
  • 28 Oct 1916 U 21 Otto Hersing Tre Fratelli D. 190 it
  • 31 Oct 1916 U 21 Otto Hersing Glenlogan 5,838 br
  • 1 Nov 1916 U 21 Otto Hersing Bernardo Canale 1,346 it
  • 1 Nov 1916 U 21 Otto Hersing Torero 767 it
  • 2 Nov 1916 U 21 Otto Hersing San Antonio O. 113 it
  • 3 Nov 1916 U 21 Otto Hersing San Giorgio 258 it
  • 23 Dec 1916 U 21 Otto Hersing Benalder (d.) 3,044 br
  • 16 Feb 1917 U 21 Otto Hersing Mayola 146 br
  • 16 Feb 1917 U 21 Otto Hersing Rose Dorothea 147 br
  • 17 Feb 1917 U 21 Otto Hersing Emilia I° 25 pt
  • 17 Feb 1917 U 21 Otto Hersing Lima 108 pt
  • 20 Feb 1917 U 21 Otto Hersing Cacique 2,917 fr
  • 22 Feb 1917 U 21 Otto Hersing Bandoeng 5,851 nl
  • 22 Feb 1917 U 21 Otto Hersing Eemland 3,770 nl
  • 22 Feb 1917 U 21 Otto Hersing Gaasterland 3,917 nl
  • 22 Feb 1917 U 21 Otto Hersing Jacatra 5,373 nl
  • 22 Feb 1917 U 21 Otto Hersing Noorderdijk 7,166 nl
  • 22 Feb 1917 U 21 Otto Hersing Normanna 2,900 nw
  • 22 Feb 1917 U 21 Otto Hersing Zaandijk 4,189 nl
  • 22 Feb 1917 U 21 Otto Hersing Menado (d.) 5,874 nl
  • 22 Apr 1917 U 21 Otto Hersing Giskö 1,643 nw
  • 22 Apr 1917 U 21 Otto Hersing Theodore William 3,057 nw
  • 29 Apr 1917 U 21 Otto Hersing Askepot 1,793 nw
  • 30 Apr 1917 U 21 Otto Hersing Borrowdale 1,268 ru
  • 3 May 1917 U 21 Otto Hersing Lindisfarne 1,703 ru
  • 6 May 1917 U 21 Otto Hersing Adansi 2,644 br
  • 8 May 1917 U 21 Otto Hersing Killarney 1,413 br
  • 27 Jun 1917 U 21 Otto Hersing Baltic 1,125 sw

Fate 22 Feb 1919 - Sunk in an accident in position 54.19N, 03.42W while on passage to surrender.

On 5 September, 1914 the small British cruiser HMS Pathfinder was torpedoed and sunk in the North Sea by U 21. This was the first warship to be sunk by a German U-boat during the First World War.

25th May 1915 HMS Triumph  

HMS Triumph

HMS Triumph, (Swiftsure class) pre-dreadnought battleship.
Built Vickers, Barrow, laid down February 1902, completed June 1904, cost £956,596.
Size: Length 462 feet 6 inch waterline 475 feet 3 inch overall, beam 71 feet 2 inches, draught 24 feet 8 inches, displacement 11,740 load 13,432 tons deep.
Propulsion: 2 shaft Triple Expansion, 12,500 ihp, speed 19 knots.

Armour: 7-3inch belt, 10inch barbettes, 10inch gun houses, 3-1inch decks.
Armament: 4 x 10inch 45 cal BL (2 x 2), 14 x 7.5inch BL (14 x 1), 14 x 14pounder QF (14 x 1), 2 x 12pounder QF (2 x 1), 4 x 6pounder (4 x 1), 2 x 18inch TT.
Crew complement 729 Offficers and ratings.

Originally designed by Sir Edward Reed for Chile to counter Argentinean armoured cruisers but owing to financial problems the ships were put up for sale before completion. The ships were purchased by the British government in December 1903 mainly to prevent their possible sale to Russia. The design emphasised speed and a heavy secondary armament at the expense of protection and main armament.

Swiftsure Class. As you would expect for a design originally for overseas navy these ships were quite distinctive from the normal British designs with wide spaced funnels and prominent cranes between them, smaller main gun turrets. The ships were only considered Second Class Battleships in British service.

The two ships had slightly different main guns as they were armed by their respective builders. They were the only British battleships to mount a 7.5 inch gun although that calibre was used in some cruisers. Likewise the 14 pounder anti torpedo boat guns were unique to this class.

World War 1 Service:

  • In reserve at Hong Kong at the start of war and re-commissioned there.
  • Took part in search for Admiral Graf Spee and captured a German collier.
  • August-November 1914 attached to Japanese Second Fleet for action against German base at Tsingtau.
  • November 1914-January 1915 under refit at Hong Kong.
  • February 1915 joined Dardanelles Squadron.
  • Took part in attacks on forts and supported landings.
  • 18 April 1915 one of her picket boats along with one from HMS Majestic destroyed the grounded British submarine E15 to prevent capture.
  • 25 May 1915 torpedoed and sunk by German submarine U21.

Upon completion of her refit in January 1915, Triumph was transferred to the Dardanelles for service in the Dardanelles Campaign. The ship departed Hong Kong on 12 January and stopped at Suez from 7 February to 12 February before moving on to join the Dardanelles Squadron. Triumph took part in the opening attack on the entrance forts on 18 February and 19 February, and joined the pre-dreadnoughts Albion and Cornwallis in using her secondary battery to silence the fort at Sedd el Bahr on 25 February. She, Albion, and Majestic were the first Allied battleships to enter the Turkish Straits during the campaign when they carried out the initial attack on the inner forts on 26 February. She also took part in the attack on Fort Dardanos on 2 March 1915. She and Swiftsure were detached from the Dardanelles on 5 March for operations against forts at Smyrna, returning to the Dardanelles on 9 March.

Triumph participated in the main attack on the Narrows forts on 18 March, and fired on Ottoman trenches at Achi Baba on 15 April. On 18 April, one of her picket boats and one from Majestic torpedoed and sank the British submarine E15, which had run aground near Fort Dardanos and was in danger of being captured by Ottoman forces. Triumph supported the main landing by the Anzac forces at Gaba Tepe on 25 April, and continued to support them through May. On 25 May, the ship was underway off Gaba Tepe, firing on Ottoman positions, with torpedo nets out and most watertight doors shut, when she sighted a submarine periscope 300 to 400 yards (270 to 370 m) off her starboard beam at about 1230 hours. It belonged to the U-boat U-21. Triumph opened fire on the periscope, but was almost immediately struck by a torpedo, which easily cut through her torpedo net, on her starboard side. A tremendous explosion resulted, and Triumph took on a list 10° to starboard. She held that list for about five minutes, then it increased to 30°. The destroyer Chelmer evacuated most of her crew before she capsized ten minutes later. She remained afloat upside down for about 30 minutes, then began to sink slowly in about 180 feet (55 m) of water. Three officers and 75 enlisted men died in her sinking.

27th May 1915 HMS Majestic  

HMS Majestic

HMS Majestic. (1895 - 1921)

Majestic Class - pre-dreadnought Battleships.

The Majestic class was a class of pre-dreadnought battleships, built under the Spencer Programme (named after the First Lord of the Admiralty, John Poyntz Spencer, 5th Earl Spencer) of 8 December 1893, that sought to counter the growing naval strength of France and the Russian Empire. With nine units commissioned, they were the largest class of battleships in history in terms of the number of member ships. This class was designed by Sir William White.

  • Ships in Majestic Class
  • Caesar
  • Hannibal
  • Illustrious
  • Jupiter
  • Magnificent
  • Majestic
  • Mars
  • Prince George
  • Victorious

When the lead ship, Majestic, was launched in 1895, at 421 ft (128 m) long and with a full-load displacement of 16,000 tons, she was the largest battleship ever built at the time. The Majestics were considered good seaboats with an easy roll and good steamers, although they suffered from high fuel consumption. They began life as coal-burners, but HMS Mars in 1905–1906 became the first battleship converted to oil-burning, and the rest were similarly converted by 1907–1908. The class was the last to have side-by-side funnels, with successor battleship classes having funnels in a line.

Except for Caesar, Hannibal, and Illustrious, they had a new design in which the bridge was mounted around the base of the foremast behind the conning tower to prevent a battle-damaged bridge from collapsing around the tower. Although the earlier ships had pear-shaped barbettes and fixed loading positions for the main guns, Caesar and Illustrious had circular barbettes and all-around loading for their main guns, which established the pattern for future classes.

Although Harvey armour had been used on battleship HMS Renown of the Centurion class, in the Majestics it was used in an entire class of British battleships for the first time. It allowed equal protection with less cost in weight compared to previous types of armour, allowing the Majestic class to have a deeper and lighter belt than previous battleships without any loss in protection.

The Majestics were given a new gun, the 46-ton BL 12 inch (305 mm) Mk VIII /35 gun. They were the first new British battleships to mount a 12 inch main battery since the 1880s. The new gun was a significant improvement on the 13.5 inch (343 mm) gun which had been fitted on the Admiral and Royal Sovereign classes that preceded the Majestics and was lighter. This saving in weight allowed the Majestic class to carry a secondary battery of twelve 6 inch (152 mm) 40-calibre guns, a larger secondary armament than in previous classes.

The Majestics were to be a benchmark for successor pre-dreadnoughts. While the preceding Royal Sovereign-class battleships had revolutionized and stabilised British battleship design by introducing the high-freeboard battleship with four main-battery guns in twin mountings in barbettes fore and aft, it was the Majestics that settled on the 12 inch (305 mm) main battery and began the practice of mounting armoured gunhouses over the barbettes; these gunhouses, although very different from the old-style, heavy, circular gun turrets that preceded them, would themselves become known as "turrets" and became the standard on warships worldwide.

More directly, the Majestic design itself also was adapted by the Imperial Japanese Navy for its own Shikishima-class pre-dreadnoughts,[6] as well as Mikasa, which was largely based on the Shikishimas.

World War 1 Service

HMS Majestic served in the Channel Fleet and Atlantic Fleet 1895–1907, then in the Home Fleet 1907–1914. Her early World War I service was in the Channel Fleet August–November 1914, as a guard ship on the British coast November–December 1914, and in the Dover Patrol December 1914 – February 1915; during the latter service she bombarded German positions in Belgium. She served in the Dardanelles Campaign February–May 1915, seeing much service in action against Ottoman Turkish forts and shore batteries before being sunk on 27 May 1915 by the German submarine U-21 while stationed off Cape Helles with the loss of 40 of her crew.

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