SM UB-46

The German UB II design improved upon the design of the UB I boats, which had been ordered in September 1914.Gardiner, p. 174. In service, the UB I boats were found to be too small and too slow. A major problem was that, because they had a single propeller shaft/engine combo, if either component failed, the U-boat became almost totally disabled.Miller, p. 48. To rectify this flaw, the UB II boats featured twin propeller shafts and twin engines (one shaft for each engine), which also increased the U-boat's top speed.Williamson, p. 13. The new design also included more powerful batteries, larger torpedo tubes, and a deck gun.Tarrant, p. 172. As a UB II boat, U-47 could also carry twice the torpedo load of her UB I counterparts, and nearly ten times as much fuel. To contain all of these changes the hull was larger, and the surface and submerged displacement was more than double that of the UB I boats.

The Imperial German Navy ordered UB-46 from AG Weser on 31 July 1915 as one of a series of six UB II boats (numbered from {{SMU|UB-42||2}} to {{SMU|UB-47||2}}). UB-46 was {{convert|36.90|m|ftin}} long and {{convert|4.37|m|ftin}} abeam. She had a single hull with saddle tanks and had a draught of {{convert|3.68|m|ftin}} when surfaced. She displaced {{convert|305|t|LT}} while submerged but only {{convert|272|t|LT}} on the surface.{{sfn|Gröner|1991|pp=23–25}}

The submarine was equipped with twin Daimler diesel engines and twin Siemens-Schuckert electric motors—for surfaced and submerged running, respectively. UB-46 had a surface speed of up to {{convert|8.82|kn}} and could go as fast as {{convert|6.22|kn}} while underwater. The U-boat could carry up to {{convert|27|t|LT}} of diesel fuel, giving her a range of {{convert|6,940|nmi}}at {{convert|5|kn}}. Her electric motors and batteries provided a range of {{convert|45|nmi}}at {{convert|4|kn}} while submerged.{{sfn|Gröner|1991|pp=23–25}}

UB-46 was equipped with two {{convert|50|cm|in|1|sp=us|adj=on}} bow torpedo tubes and could carry four torpedoes. The U-boat was also armed with one 8.8 cm SK L/30 naval gun deck gun.{{sfn|Gröner|1991|pp=23–25}}

UB-46 was laid down by AG Weser at its Bremen shipyard on 4 September 1915. As one of six U-boats selected for service in the Mediterranean while under construction, UB-46 was broken into railcar-sized components and shipped overland to the Austro-Hungarian port of Pola.Halpern, p. 383.Miller, p. 49. Shipyard workers from Weser assembled the boat and her five sisters at Pola, where she was launched on 17 June.

SM UB-46 was commissioned into the German Imperial Navy on 12 June 1916 under the command of Oberleutnant zur See Cäsar Bauer.The 27-year-old Bauer had been in the Navy's April 1904 cadet class with 20 other future U-boat captains, including Wilhelm Canaris. For Bauer information, see: {{cite Uboat.net

|name=Cäsar Bauer

|id=17

|type=1comm

|website=German and Austrian U-Boats of World War I – Kaiserliche Marine – Uboat.net

|access-date=12 February 2009

}}
For cadet crew information, see: {{cite Uboat.net

|name=Crew 4/04

|id=4%2F04

|type=1crew

|access-date=12 February 2009

}} UB-46, Bauer's third U-boat command,{{cite Uboat.net

|name=Cäsar Bauer

|id=17

|type=1comm

|access-date=12 February 2009

}} Bauer had previously been in command of {{SMU|UC-12||2}} and {{SMU|UC-14||2}}. was assigned to the Navy's Pola Flotilla ({{langx|de|link=no|Deutsche U-Halbflotille Pola}}). Although the flotilla was based in Pola, the site of the main Austro-Hungarian Navy base, boats of the flotilla operated out of the Austro-Hungarian base at Cattaro which was located farther south and closer to the Mediterranean. German U-boats typically returned to Pola only for repairs.Halpern, p. 384. After a month at the helm of UB-46, Bauer was promoted to Kapitänleutnant.

On 2 August, Bauer achieved his first success in command of UB-46 when the Japanese steamer Kohina Maru was sunk off Alexandria just short of her destination of Port Said.{{cite Uboat.net

|name=Kohina Maru

|id=3366

|type=1ship

|access-date=12 February 2009

}} A week later the U-boat sank the Greek sailing vessel Basileios which was headed back to the Adriatic from Egypt.{{cite Uboat.net

|name=Basileios

|id=660

|type=1ship

|access-date=12 February 2009

}} Uboat.net reports that the vessel was also referred to under the name Vassilaos. On 2 October, Bauer torpedoed Huntsfall which was carrying hay to Salonica, and took the ship's master prisoner.{{cite Uboat.net

|name=Huntsfall

|id=2929

|type=1ship

|access-date=12 February 2009

}} The {{GRT|4,331|disp=long|link=off}} British steamer was the largest ship sunk by UB-46.

After Germany's conquest of Romania (see Romania during World War I), the German Imperial Navy had sufficient fuel oil for submarines located in the Black Sea. UB-46 and three of her sister ships in the Pola Flotilla were ordered to Constantinople and, en route, had to navigate through the Dardanelles, which had been heavily mined by the Allies in the middle of 1916.Halpern, pp. 248–49.The other three boats were {{SMU|UB-42||2}}, {{SMU|UB-44||2}}, and {{SMU|UB-45||2}}. UB-46 joined the Constantinople Flotilla ({{langx|de|link=no|U-boote der Mittelmeerdivision in Konstantinopal}}) on 7 October.

File:Site of ub-46 sinking.gif

The German submarines in the Black Sea accomplished little, sinking only six ships between August and the end of the year.Halpern, p. 249. UB-46 sank one of the six ships when she sent down the 116 GRT Russian ship Melanie north of Cape Tarkhan on 7 November.{{cite Uboat.net

|name=Melanie

|id=4065

|type=1ship

|access-date=12 February 2009

}} Melanie was the last ship sunk by UB-46. By early December, UB-46 was based out of Varna, Bulgaria.Messimer, p. 167.

On 7 December 1916, the stern of UB-46 struck a Russian mine {{convert|300|m|ft}} off the shore of the Turkish village of Akpınar, approximately {{convert|30|km|mi}} north-west of the entrance to the Bosphorus."German UB-46 Submarine". Dardanelles Naval Museum, Çanakkale The vessel's entire complement (reported by Helgason as 20) perished in the sinking.

A {{convert|16|m|ft}} portion of the wreck comprising the forward section of the torpedo room and battery compartment was located in 1993 during coal extraction operations and was salvaged by the Turkish navy; the remainder of the vessel could not be located. She was put on display in an outdoor exhibit at the Turkish Naval Museum in Istanbul.{{cite web

|last=Helgason

|first=Guðmundur

|title=The Galleries: UB 46 in Turkey

|url=http://uboat.net/gallery/index.html?gallery=ub46

|website=Uboat.net

|access-date=12 February 2009

|archive-date=8 November 2010

|archive-url=https://web.archive.org/web/20101108182420/http://www.uboat.net/gallery/index.html?gallery=ub46

|url-status=dead

}} The wreckage was transferred to the Dardanelles Naval Museum at Çanakkale in 2008, where the remains of the vessel are currently on display.{{cite web|url=http://www.denizhaber.com.tr/dkk-sgk/14475/92-yillik-alman-denizaltisi-sergileniyor|title=92 yıllık Alman denizaltısı sergileniyor|work=Deniz Haber|language=tr|date=18 July 2008|access-date=3 March 2010|archive-date=23 April 2022|archive-url=https://web.archive.org/web/20220423000150/http://www.denizhaber.com.tr/dkk-sgk/14475/92-yillik-alman-denizaltisi-sergileniyor|url-status=dead}}

{{Reflist|group=Note}}

{{Reflist}}

{{Refbegin}}

• {{Cite book| last = Bendert| first = Harald |title=Die UB-Boote der Kaiserlichen Marine, 1914-1918. Einsätze, Erfolge, Schicksal | location = Hamburg | publisher = Verlag E.S. Mittler & Sohn GmbH| year = 2000 | isbn = 3-8132-0713-7 | language = de}}
• {{cite book

|last1=Gröner

|first1=Erich

|last2=Jung

|first2=Dieter

|last3=Maass

|first3=Martin

|translator-last1=Thomas

|translator-first1=Keith

|translator-last2=Magowan

|translator-first2=Rachel

|year=1991

|title=German Warships 1815–1945, U-boats and Mine Warfare Vessels

|volume=2

|location=London

|publisher=Conway Maritime Press

|isbn=0-85177-593-4

|ref=CITEREFGröner1991

}}

• {{cite book |last1=Rössler |first1=Eberhard |title=Die deutschen U-Boote und ihre Werften: eine Bilddokumentation über den deutschen U-Bootbau; in zwei Bänden |date=1979 |publisher=Bernard & Graefe |location=Munich |volume=I|isbn=3-7637-5213-7|url=https://books.google.com/books?id=QIvfAAAAMAAJ |language=de}}
• {{cite book | editor1-last=Gardiner | editor1-first=Robert | editor2-last=Gray | editor2-first=Randal |title=Conway's All the World's Fighting Ships 1906–1921 | location = Annapolis, Maryland | publisher = Naval Institute Press | year = 1985 | isbn = 978-0-87021-907-8 | oclc = 12119866 }}
• {{cite book | last1 = Gibson | first1 = R. H. | first2 = Maurice | last2=Prendergast |title=The German Submarine War, 1914–1918 | location = Annapolis, Maryland | publisher = Naval Institute Press | year = 2003 | orig-year = 1931 | isbn = 978-1-59114-314-7 | oclc = 52924732 }}
• {{cite book | last = Halpern | first = Paul G. |title=A Naval History of World War I | location = Annapolis, Maryland | publisher = Naval Institute Press | year = 1994 | isbn = 978-0-87021-266-6 | oclc = 28411665 }}
• {{cite book | last = Messimer | first = Dwight R. |title=Verschollen: World War I U-boat losses | location = Annapolis, Maryland | publisher = Naval Institute Press | year = 2002 | isbn = 978-1-55750-475-3 | oclc = 231973419 }}
• {{cite book | last = Miller | first = David |title=The Illustrated Directory of Submarines of the World | location = St. Paul, Minnesota | publisher = MBI Pub. Co | year = 2002 | isbn = 978-0-7603-1345-9 | oclc = 50208951 }}
• {{cite book | last = Miller | first = David |title=The Illustrated Directory of Submarines of the World | location = St. Paul, Minnesota | publisher = MBI Pub. Co | year = 2002 | isbn = 978-0-7603-1345-9 | oclc = 50208951 }}
• {{cite book | last = Tarrant | first = V. E. |title=The U-Boat Offensive: 1914–1945 | location = Annapolis, Maryland | publisher = Naval Institute Press | year = 1989 | isbn = 978-0-87021-764-7 | oclc = 20338385 }}
• {{cite book |first=Gordon|last=Williamson|author-link=Gordon Williamson (writer)|title=U-boats of the Kaiser's Navy | location = Oxford | publisher = Osprey | year = 2002 | isbn = 978-1-84176-362-0 | oclc = 48627495 }}

{{Refend}}

{{German Type UB II submarines}}

{{December 1916 shipwrecks}}

{{Oldest surviving ships (pre-1919)}}

{{coord|41|26|N|28|35|E|display=title}}

{{Good article}}

{{DEFAULTSORT:Ub046}}

Category:German Type UB II submarines

Category:U-boats commissioned in 1916

Category:World War I submarines of Germany

Category:Maritime incidents in 1916

Category:U-boats sunk in 1916

Category:U-boats sunk by mines

Category:World War I shipwrecks in the Black Sea

Category:Ships preserved in museums

Category:1916 ships

Category:Submarines lost with all hands