SM U-79 was one of the 329 submarine

Submarine

A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...

s serving in the Kaiserliche Marine

Kaiserliche Marine

The Imperial German Navy was the German Navy created at the time of the formation of the German Empire. It existed between 1871 and 1919, growing out of the small Prussian Navy and Norddeutsche Bundesmarine, which primarily had the mission of coastal defense. Kaiser Wilhelm II greatly expanded...

(Imperial German Navy) in World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

. U-79 was engaged in the naval warfare

Naval warfare of World War I

Naval warfare in World War I was mainly characterized by the efforts of the Allied Powers, with their larger fleets and surrounding position, to blockade the Central Powers by sea, and the efforts of the Central Powers to break that blockade or to establish an effective blockade of the United...

 and took part in the First Battle of the Atlantic.

Operations

SM U-79 was commissioned

Ship commissioning

Ship commissioning is the act or ceremony of placing a ship in active service, and may be regarded as a particular application of the general concepts and practices of project commissioning. The term is most commonly applied to the placing of a warship in active duty with its country's military...

 by Kaptlt. Jess, who was replaced by Kaptlt. Rohrbeck in January 1917. Rohrbeck would be replaced by Kaptlt. Stevogt. U-79 came off the stocks at Hamburg (Vulcan) in 1916, and joined the Kiel School, where she is known to have been in July, and left Kiel for Wilhelmshaven about the end of July to join the 1st Half Flotilla.

Between 6 and 26 August 1916, she laid 34 mine

Naval mine

A naval mine is a self-contained explosive device placed in water to destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, an enemy vessel...

s off the south coast of Ireland. She fired on a special service vessel north-west of Ireland on the night of 19 August; the torpedo

Torpedo

The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...

 missed. In the period 26 September to 14 October 1916, she laid mines in the Firth of Clyde

Firth of Clyde

The Firth of Clyde forms a large area of coastal water, sheltered from the Atlantic Ocean by the Kintyre peninsula which encloses the outer firth in Argyll and Ayrshire, Scotland. The Kilbrannan Sound is a large arm of the Firth of Clyde, separating the Kintyre Peninsula from the Isle of Arran.At...

.

Patrolling off Portugal, via the English Channel, between 21 December 1916 and 28 January 1917, she sank eight steamers and one sailing ship, as well as capturing the Norwegian steamer Nanna on 24 January. On her return journey, by way of the Irish Channel, U-79 compelled Nanna to take her under tow to the Danish coast, likely as a result of engine damage she reported 26 January.

On 1 April 1917, she departed to lay mines in Inishtrahull Sound, but could not complete her task due to engine trouble, and returned on 21 April. She made three more minelaying patrols in 1917, one off the Butt of Lewis

Butt of Lewis

The Butt of Lewis is the most northerly point of the Isle of Lewis in the Outer Hebrides. The headland, which lies in the North Atlantic, is frequently battered by heavy swells and storms.-Lighthouse:...

 between 6 June and 4 July; one in Rathlin Sound and off Inishtrahull Island

Inishtrahull Island

Inishtrahull is located approx north-east of Malin Head, Inishowen, County Donegal. It is the most northerly island of Ireland. The most northerly landfall of Ireland, the Tor Beg rock is located another one kilometer to the North West of Inishtrahull. Inishtrahull has an area of...

, between 12 September and 15 October, during which she also sank the armoured cruiser

Armored cruiser

The armored cruiser was a type of warship of the late 19th and early 20th centuries. Like other types of cruiser, the armored cruiser was a long-range, independent warship, capable of defeating any ship apart from a battleship, and fast enough to outrun any battleships it encountered.The first...

  off Rathlin Island, 11 October, avoiding Heligoland Bight

Heligoland Bight

The Heligoland Bight, also known as Helgoland Bight, is a bay which forms the southern part of the German Bight, itself a bay of the North Sea, located at the mouth of the Elbe river...

 (per a 10 October general order) on her return; and one between 17 and 20 December, off the Dutch coast, transiting Heligoland Bight inbound and outbound on this occasion. She departed for a repeat of this mission 1 January 1918, but was forced to return 5 January due to compass trouble.

She carried out training off Augustenhof Lighthouse, in the Baltic Sea, from 5 to 9 February, before departing on her next patrol, to lay mines off Holland, returning 19 February, again avoiding Heligoland.

British Naval Intelligence

Room 40

In the history of Cryptanalysis, Room 40 was the section in the Admiralty most identified with the British cryptoanalysis effort during the First World War.Room 40 was formed in October 1914, shortly after the start of the war...

 (better known as Room 40) records her at Norderney

Norderney

Norderney is one of the seven populated East Frisian Islands off the North Sea coast of Germany. It is also a municipality in the district of Aurich in Lower Saxony....

 on 2 May 1918, and possibly in the Elbe on 9 November. On 21 November 1918, she was surrendered at Harwich

Harwich

Harwich is a town in Essex, England and one of the Haven ports, located on the coast with the North Sea to the east. It is in the Tendring district. Nearby places include Felixstowe to the northeast, Ipswich to the northwest, Colchester to the southwest and Clacton-on-Sea to the south...

.

Original documents from Room 40

External links

• Photos of cruises of German submarine U-54 in 1916-1918.
• A 44 min. German film from 1917 about a cruise of the German submarine U-35.
• Uboat.net: More detailed information about U-79.
• Room 40: original documents, photos and maps about World War I German submarine warfare and British Room 40
  Room 40
  In the history of Cryptanalysis, Room 40 was the section in the Admiralty most identified with the British cryptoanalysis effort during the First World War.Room 40 was formed in October 1914, shortly after the start of the war...
  
   Intelligence from The National Archives, Kew, Richmond, UK.