View source for German submarine U-28 (1936)

{{Short description|German World War II submarine}}
{{other ships|German submarine U-28}}
{{good article}}
{|{{Infobox ship begin}}
{{Infobox ship image
|Ship image=U-33 - Unterseeboot (1936) in Brockhaus 1937.jpg
|Ship image size=300px
|Ship caption=''U-33'', a typical Type VIIA boat
}}
{{Infobox ship career
|Hide header=
|Ship country=[[Nazi Germany]]
|Ship flag={{shipboxflag|Nazi Germany|naval}}
|Ship name=''U-28''
|Ship ordered=1 April 1935
|Ship builder=[[DeSchiMAG]] [[AG Weser]], [[Bremen]]
|Ship yard number=909
|Ship original cost={{Reichsmark|4,189,000|link=yes}}
|Ship laid down =2 December 1935
|Ship launched=14 July 1936
|Ship commissioned=12 September 1936
|Ship homeport=
|Ship motto=
|Ship nickname=
|Ship fate=Damaged in a collision, 17 March 1944,<ref name="uboatnet"/> stricken 4 August 1944
|Ship notes=
}}
{{Infobox ship characteristics
|Hide header=
|Header caption=
|Ship class=[[German Type VII submarine#Type VIIA|Type VIIA]] [[submarine]]
|Ship displacement=
*{{convert|626|t|LT|0|lk=on}} surfaced
*{{convert|745|t|LT|0|abbr=on}} submerged
|Ship length=
*{{convert|64.51|m|ftin|abbr=on}} [[o/a]]
*{{convert|45.50|m|ftin|abbr=on}} pressure hull
|Ship beam=
*{{convert|5.85|m|ftin|abbr=on}} o/a
*{{convert|4.70|m|ftin|abbr=on}} pressure hull
|Ship height={{convert|9.50|m|ftin|abbr=on}}
|Ship draught={{convert|4.37|m|ftin|abbr=on}}
|Ship power=
*{{convert|2100|–|2310|PS|kW bhp|abbr=on}} (diesels)
*{{convert|750|PS|kW shp|abbr=on}} (electric)
|Ship propulsion=
*2 shafts
*2 × [[diesel engine]]s
*2 × [[Motor-generator|electric motors]]
|Ship speed=
*{{convert|17|kn|lk=in}} surfaced
*{{convert|8|kn}} submerged
|Ship range=
*{{convert|6,200|nmi|abbr=on|lk=on}} at {{convert|10|kn}} surfaced
*{{convert|73|–|94|nmi|abbr=on}} at {{convert|4|kn}} submerged
|Ship test depth=
*{{convert|220|m|ft|abbr=on}}
*Crush depth: {{convert|230|–|250|m|ft|abbr=on}}
|Ship complement=4 officers, 40–56 enlisted
|Ship sensors=''[[Gruppenhorchgerät]]''
|Ship armament=
*5 × {{convert|53.3|cm|in|0|abbr=on}} [[torpedo tube]]s (four bow, one stern)
*11 [[torpedo]]es ''or'' 22 TMA [[Naval mine|mine]]s ''or'' 33 TMB mines
*1 × [[8.8 cm SK C/35 naval gun|{{convert|8.8|cm|in|2|abbr=on}} deck gun]] (220 rounds)
*1 × [[2 cm FlaK 30|{{convert|2|cm|in|sp=us|abbr=on}} C/30]] [[anti-aircraft gun]]
|Ship notes=
}}
{{Infobox service record
|is_ship=yes
|label=Service record<ref name="uboatnet">{{cite web
 |url=http://uboat.net/boats/u28.htm
 |title=The Type VIIA boat U-28
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=18 December 2009
}}</ref><ref>{{cite web
 |url=http://uboat.net/boats/patrols/u28.html
 |title=War Patrols by German U-boat U-28
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=18 December 2009
}}</ref>
|partof=
*[[2nd U-boat Flotilla]]
*12 September 1936 – 9 November 1940
*[[24th U-boat Flotilla]]
*10 November 1940 – 30 November 1943
*[[22nd U-boat Flotilla]]
*1 December 1943 – 17 March 1944
|codes=M 27 436
|commanders=
*''[[Kptlt.]]'' Wilhelm Ambrosius
*12 September 1936 – 1 November 1938
*''Kptlt.'' Hans-Günther Looff
*1936 / 37 – 30 September 1937
*''[[Oblt.z.S.]]'' [[Fritz-Julius Lemp]]
*28 October – November 1938
*''Oblt.z.S.'' / ''Kptlt.'' [[Günter Kuhnke]]
*28 October 1938 – 16 November 1940
*''Oblt.z.S.'' [[Friedrich Guggenberger]]
*16 November 1940 – 11 February 1941
*''Oblt.z.S.'' Heinrich Ratsch
*12 February – 21 June 1941
*''Oblt.z.S.'' Hermann Eckhardt
*22 June 1941 – 20 March 1942
*''Oblt.z.S.'' [[Karl-Heinz Marbach]]
*1 July – 30 November 1942
*''[[Lt.z.S.]]'' / ''Oblt.z.S.'' Uwe Christiansen
*1 December 1942 – July 1943
*''Lt.z.S.'' / ''Oblt.z.S.'' Erich Krempl
*July – 1 December 1943
*''Oblt.z.S.'' Dietrich Sachse
*2 December 1943 – 17 March 1944
|operations=*6 patrols:
*1st patrol:
*19 August – 29 September 1939
*2nd patrol:
*8 November – 18 December 1939
*3rd patrol:
*18 February – 23 March 1940
*4th patrol:
*20 May – 6 July 1940
*5th patrol:
*a. 11 August – 17 September 1940
*b. 4 – 6 Oct 1940
*6th patrol:
*12 October – 15 November 1940
|victories=
*11 merchant ships sunk <br>({{GRT|42,252}})
*1 auxiliary warship sunk <br>({{GRT|4,443}})
*1 merchant ship total loss <br>({{GRT|9,577}}) 
*2 merchant ships damaged <br>({{GRT|10,067}})
}}
|}

'''German submarine ''U-28''''' was a [[German Type VII submarine#Type VIIA|Type VIIA]] [[U-boat]] of [[Nazi Germany]]'s ''[[Kriegsmarine]]'' during [[World War II]].

Her keel was [[Keel laying|laid down]] on 2 December 1935, by [[DeSchiMAG]] [[AG Weser]] of [[Bremen]]. She was [[ceremonial ship launching|launched]] on 14 July 1936, and [[ship commissioning|commissioned]] into ''Kriegsmarine'' on 12 September 1936, with ''[[Kapitänleutnant]]'' Wilhelm Ambrosius in command. Ambrosius was succeeded by nine other commanding officers over the next eight years.<ref name="uboatnet"/>

''U-28'' conducted seven war patrols between 19 August 1939 and 15 November 1940, all under the command of ''[[Kapitänleutnant]]'' [[Günter Kuhnke]], sinking 13 ships totaling {{GRT|56,272|disp=long}} and damaging two others totaling {{GRT|10,067}}.<ref name="uboatnet"/>

After her third patrol, ''U-28'' became a training vessel and was used to bring new U-boat crews up to standard. She was sunk in a training accident on 17 March 1944 and stricken on 4 August 1944.<ref name="uboatnet"/>

==Construction and design==

===Construction===
''U-28'' was ordered by the ''[[Kriegsmarine]]'' on 1 April 1935 as part of the German [[Plan Z]] in violation of the [[Treaty of Versailles]]. Her keel was [[Keel laying|laid down]] in the [[AG Weser]] shipyard in Bremen as yard number 909 on 2 December 1935. After about ten months of construction, she was [[Ceremonial ship launching|launched]] on 14 July 1936 and [[Ship commissioning|commissioned]] into the ''Kriegsmarine'' as the third Type VIIA submarine on 12 September 1936 under the command of ''Kapitänleutnant'' Wilhelm Ambrosius.<ref name="uboatnet"/>

===Design===
{{main|German Type VII submarine}}
Like all Type VIIA submarines, ''U-28'' displaced {{convert|626|t|LT|0}} while surfaced and {{convert|745|t|LT|0|abbr=on}} when submerged. She was {{convert|64.51|m|ftin|abbr=on}} in overall length and had a {{convert|45.50|m|ftin|abbr=on}} pressure hull. ''U-28''{{'}}s propulsion consisted of two [[MAN SE|MAN]] 6-cylinder 4-stroke M 6 V 40/46 [[diesel engine]]s that totaled {{convert|2100|–|2310|PS|kW bhp|abbr=on}}. Her maximum [[Revolutions per minute|rpm]] was between 470 and 485. The submarine was also equipped with two [[Brown, Boveri & Cie]] GG UB 720/8 electric motors that totaled {{convert|750|PS|kW shp|abbr=on}}. Their maximum rpm was 322. These power plants gave ''U-28'' a maximum speed of {{convert|17|kn|lk=in}} while surfaced and {{convert|8|kn}} when submerged. She had a range of {{convert|6,200|nmi|abbr=on|lk=on}} while traveling at {{convert|10|kn}} on the surface and {{convert|73|–|94|nmi|abbr=on}} at {{convert|4|kn}} when submerged.

The U-boat's test depth was {{convert|220|m|ft|abbr=on}} but she could go as deep as {{convert|230|–|250|m|ft|abbr=on}} without having her hull crushed. ''U-28''{{'}}s armament consisted of five {{convert|53.3|cm|in|0|abbr=on}} [[torpedo tube]]s, four in the bow and one astern. She could carry up to 11 torpedoes, 22 TMA mines, or 33 TMB mines. ''U-28'' was also equipped with a C35 88&nbsp;mm gun/L45 [[deck gun]] with 220 rounds. Her anti-aircraft defenses consisted of one [[2 cm FlaK 30|{{convert|2|cm|in|abbr=on}}]] [[anti-aircraft gun]].{{sfn|Gröner|1991|pp=43–44}}

==Service history==

===First patrol===
''U-28''{{'}}s first war patrol took place from 19 August to 29 September 1939. On 14 September, near the mouth of [[St George's Channel]], ''U-28'' sank a 5,000 GRT freighter, her only success of the patrol.<ref>{{cite web
 |url=http://uboat.net/boats/patrols/patrol_196.html
 |title=Patrol info for U-28 (First patrol)
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=18 December 2009
}}</ref>

===Second patrol===
''U-28''{{'}}s second war patrol took place from 8 November to 12 December 1939. She was tasked with [[Minelayer|laying a minefield]] near the port city of [[Swansea]]. En route to [[Bristol]], ''U-28'' sank two ships: the 5,000 GRT Dutch tanker MV ''Sliedrecht'' and the 5,100 GRT British freighter SS ''Royston Grange''. ''U-28'' then laid her minefield and returned to port in Germany. While the minefield was not an immediate success, it sank the 9,600 GRT British freighter {{SS|Protesilaus}} 60 days after it was laid.<ref>{{cite web
 |url=http://uboat.net/boats/patrols/patrol_197.html
 |title=Patrol of U-boat U-28 (Second patrol)
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=18 December 2009
}}</ref>

===Third patrol===
''U-28''{{'}}s third sortie took place from 18 February to 25 March 1940. She was instructed to lay mines off the British Naval Base at [[HMNB Portsmouth|Portsmouth]]. After laying the minefield, she went on to sink two ships for 11,200 GRT.<ref>{{cite web
 |url=http://uboat.net/boats/patrols/patrol_198.html
 |title=Patrol info for U-28 (Third patrol)
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=18 December 2009
}}</ref>

===Fourth patrol===
''U-28''{{'}}s fourth war patrol took place from 8 June to 7 July 1940. She was sent to the [[Western Approaches]] and turned in an average performance of sinking three ships totalling 10,300 GRT.<ref>{{cite web
 |url=http://uboat.net/boats/patrols/patrol_199.html
 |title=Patrol info for U-28 (Fourth patrol)
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=18 December 2009
}}</ref> The Irish government sought an explanation from Germany for the sinking of the neutral Greek ship ''[[Adamandios Georgandis]]'' "the entire cargo of which comprised grain for exclusive consumption in Éire".<ref>{{cite book |last=Duggan |first=John P |title=Herr Hempel |publisher=Irish Academic Press |year=2003 |page=111 |isbn=0-7165-2757-X}}</ref> She had been sailing from [[Rosario]], Argentina to [[Cork (city)|Cork]] with a cargo of [[wheat]] when she was torpedoed and sunk<ref>{{cite web
 |url=http://uboat.net/allies/merchants/ships/363.html
 |title=Adamandios Georgandis
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=2009-08-26
}}</ref> south-west of Ireland at {{coord|43|35|N|11|15|W}}.

===Fifth patrol===
''U-28''{{'}}s fifth war patrol took place from 11 August to 17 September 1940 and was one of Kuhnke's most productive. In August, she sank two ships for 5,500 GRT. On 10 September, ''U-28'' found and tracked [[ON convoys|Convoy OA 210]]. In the early morning darkness of 11 September, ''U-28'' attacked the convoy, claiming two large freighters (13,000 GRT each) sunk and one 10,000 GRT tanker damaged, bringing Kuhnke's total for the patrol to five ships for 30,000 GRT. However, during the postwar analysis, he was only credited with sinking a 2,000 GRT Dutch freighter and damaging a 4,700 GRT British freighter, which, combined with his earlier sinkings, brought his total to four ships for 9,945 GRT. On his return to [[Lorient]], France, Kuhnke was awarded the [[Knight's Cross of the Iron Cross|Knight's Cross]] for his work.<ref>{{cite web
 |url=http://uboat.net/boats/patrols/patrol_200.html
 |title=Patrol info for U-28 (Fifth patrol)
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=18 December 2009
}}</ref>

===Sixth patrol===
''U-28''{{'}}s sixth and final war patrol took her from Lorient back to Germany. Hampered by heavy seas and foul weather, ''U-28'' sank only half a ship for 2,694 GRT.; ''U-28'' and {{GS|U-31|1936|2}} shared credit for the sinking of the SS ''Matina''. On 15 November 1940, she returned to Germany and was turned over to the training command. Günter Kuhnke proceeded to command {{GS|U-125|1940|2}}.<ref>{{cite web
 |url=http://uboat.net/boats/patrols/patrol_202.html
 |title=Patrol info for U-28 (Sixth patrol)
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=18 December 2009
}}</ref>

==Fate==
''U-28'' sank by accident on 17 March 1944, at the U-boat pier in [[Neustadt in Holstein|Neustadt]], Germany. During a training exercise, the boat had passed under a dummy freighter used for target practice. The commander-in-training failed to note the position of the stationary freighter, and the U-boat's [[conning tower]] was ripped off. Water flooded the control room, but the other compartments remained intact. The crew escaped by slowly equalizing the water pressure in the boat and swimming to the surface. The boat was raised in March 1944, but was stricken on 4 August. The submarine's crew suffered no casualties during her career.<ref name="uboatnet"/>

==Wolfpacks==
''U-28'' took part in one [[Wolfpack (naval tactic)|wolfpack]], namely:
* [[Wolfpack Prien|Prien]] (12 – 17 June 1940)

==Summary of raiding history==
{|class="wikitable sortable" border="1"
|-
! Date||Name of Ship||Nationality||Tonnage<ref group=Note name=tonnage>Merchant ship tonnages are in [[gross register tons]]. Military vessels are listed by tons [[displacement (ship)|displacement]].</ref>||Fate<ref>{{cite web
 |url=http://uboat.net/boats/successes/u28.html
 |title=Ships hit by U-28
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=8 December 2014
}}
</ref>
|-
| align="right"|14 September 1939
| align="left" |''[[List of shipwrecks in September 1939#14 September|Vancouver City]]''
| align="left" |{{flag|United Kingdom|civil}}
| align="right"|4,955
| align="left" |Sunk
|-
| align="right"|17 November 1939
| align="left" |''[[Sliedrecht (tanker)|Sliedrecht]]''
| align="left" |{{flag|Netherlands}}
| align="right"|5,133
| align="left" |Sunk
|-
| align="right"|25 November 1939
| align="left" |''[[List of shipwrecks in November 1939#25 November|Royston Grange]]''
| align="left" |{{flag|United Kingdom|civil}}
| align="right"|5,144
| align="left" |Sunk
|-
| align="right"|21 January 1940
| align="left" |''[[List of shipwrecks in January 1940#21 January|Protesilaus]]''
| align="left" |{{flag|United Kingdom|civil}}
| align="right"|9,577
| align="left" |Total loss (mine)
|-
| align="right"|9 March 1940
| align="left" |''[[List of shipwrecks in March 1940#9 March|P. Margoronis]]''
| align="left" |{{flag|Greece}}
| align="right"|4,979
| align="left" |Sunk
|-
| align="right"|11 March 1940
| align="left" |''[[List of shipwrecks in March 1940#11 March|Eulota]]''
| align="left" |{{flag|Netherlands}}
| align="right"|6,236
| align="left" |Sunk
|-
| align="right"|18 June 1940
| align="left" |''[[List of shipwrecks in June 1940#18 June|Samartia]]''
| align="left" |{{flag|Finland}}
| align="right"|2,417
| align="left" |Sunk
|-
| align="right"|19 June 1940
| align="left" |''[[List of shipwrecks in June 1940#19 June|Adamandios Georgandis]]''
| align="left" |{{flag|Greece}}
| align="right"|3,443
| align="left" |Sunk
|-
| align="right"|21 June 1940
| align="left" |[[Q-ship|HMS ''Prunella'']]
| align="left" |{{navy|United Kingdom}}
| align="right"|4,443
| align="left" |Sunk
|-
| align="right"|27 August 1940
| align="left" |''[[List of shipwrecks in August 1940#27 August|Eva]]''
| align="left" |{{flag|Norway}}
| align="right"|1,599
| align="left" |Sunk
|-
| align="right"|28 August 1940
| align="left" |''[[List of shipwrecks in August 1940#28 August|Kyno]]''
| align="left" |{{flag|United Kingdom|civil}}
| align="right"|3,946
| align="left" |Sunk
|-
| align="right"|9 September 1940
| align="left" |''[[List of shipwrecks in September 1940#9 September|Mardinian]]''
| align="left" |{{flag|United Kingdom|civil}}
| align="right"|2,434
| align="left" |Sunk
|-
| align="right"|11 September 1940
| align="left" |''[[List of shipwrecks in September 1940#11 September|Harpenden]]''
| align="left" |{{flagcountry|United Kingdom|civil}}
| align="right"|4,678
| align="left" |Damaged
|-
| align="right"|11 September 1940
| align="left" |''[[List of shipwrecks in September 1940#11 September|Maas]]''
| align="left" |{{flag|Netherlands}}
| align="right"|1,966
| align="left" |Sunk
|-
| align="right"|26 October 1940
| align="left" |''[[List of shipwrecks in October 1940#26 October|Matina]]''
| align="left" |{{flag|United Kingdom|civil}}
| align="right"|5,389
| align="left" |Damaged
|}

==References==

===Notes===
{{Reflist|group=Note}}

===Citations===
{{reflist}}

==Bibliography==
{{Refbegin}}
*{{cite book | last1 = Busch | first1 = Rainer | last2 = Röll | first2 = Hans-Joachim | translator-last = Brooks | translator-first = Geoffrey | title = German U-boat commanders of World War II : a biographical dictionary | publisher = Greenhill Books, Naval Institute Press | location = London, Annapolis, Md | year = 1999 | isbn = 1-55750-186-6 }}
*{{cite book
|last1=Busch
|first1=Rainer
|last2=Röll
|first2=Hans-Joachim
|title=Deutsche U-Boot-Verluste von September 1939 bis Mai 1945
|trans-title=German U-boat losses from September 1939 to May 1945
|series=Der U-Boot-Krieg
|volume=IV
|publisher=Mittler
|location=Hamburg, Berlin, Bonn
|year=1999
|isbn=3-8132-0514-2
|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=U-boats and Mine Warfare Vessels
|volume=2
|series=German Warships 1815–1945
|location=London
|publisher=Conway Maritime Press
|isbn=0-85177-593-4
|ref=CITEREFGröner1991
}}
*{{cite book
|last=Edwards
|first=Bernard
|title=Dönitz and the Wolf Packs - The U-boats at War
|year=1996
|isbn=0-304-35203-9
|pages=23, 42, 47
|ref={{sfnRef|Edwards}}
}}
{{Refend}}

==External links==
*{{Cite web
 |url=http://uboat.net/boats/u28.htm
 |title=The Type VIIA boat U-28
 |last=Helgason
 |first=Guðmundur
 |website=German U-boats of WWII - uboat.net
 |access-date=8 December 2014
}}
*{{cite web
|url=http://www.u-boot-archiv.de/dieboote/u0028.html
|title=''U 28''
|last=Hofmann
|first=Markus
|website=Deutsche U-Boote 1935-1945 - u-boot-archiv.de
|language=de
|access-date=7 December 2014
}}

{{German Type VII submarines}}
{{March 1944 shipwrecks}}

{{coord|54|07|N|10|50|E|type:landmark_source:dewiki|display=title}}

{{Use dmy dates|date=October 2014}}

{{DEFAULTSORT:U0028}}
[[Category:1936 ships]]
[[Category:German Type VIIA submarines]]
[[Category:Military units and formations of Nazi Germany in the Spanish Civil War]]
[[Category:Ships built in Bremen (state)]]
[[Category:U-boats sunk in collisions]]
[[Category:U-boat accidents]]
[[Category:U-boats commissioned in 1936]]
[[Category:U-boats sunk in 1944]]
[[Category:World War II submarines of Germany]]
[[Category:Maritime incidents in March 1944]]