German submarine U-309
|Ordered:||5 June 1941|
|Builder:||Flender Werke, Lübeck|
|Laid down:||24 January 1942|
|Launched:||5 December 1942|
|Commissioned:||27 January 1943|
|Fate:||Sunk, 16 February 1945|
|Type:||Type VIIC submarine|
|Displacement:||769 tonnes (757 long tons) surfaced
871 t (857 long tons) submerged
|Length:||67.1 m (220 ft 2 in) o/a
50.5 m (165 ft 8 in) pressure hull
|Beam:||6.2 m (20 ft 4 in) o/a
4.7 m (15 ft 5 in) pressure hull
|Draft:||4.74 m (15 ft 7 in)|
|Propulsion:||2 × supercharged Germaniawerft 6-cylinder 4-stroke F46 diesel engines, totalling 2,800–3,200 bhp (2,100–2,400 kW). Max rpm: 470-490
2 × GL RP 137/c electric motors, totalling 750 shp (560 kW) and max rpm: 296.
|Speed:||17.7 knots (32.8 km/h; 20.4 mph) surfaced
7.6 knots (14.1 km/h; 8.7 mph) submerged
|Range:||15,170 km (8,190 nmi) at 10 knots (19 km/h; 12 mph) surfaced
150 km (81 nmi) at 4 knots (7.4 km/h; 4.6 mph) submerged
|Test depth:||230 m (750 ft)
Crush depth: 250–295 m (820–968 ft)
|Complement:||44–52 officers and ratings|
|Armament:||5 × 53.3 cm (21 in) torpedo tubes (four bow, one stern)
14 × G7e torpedoes or 26 TMA mines
1 × 8.8 cm (3.46 in) deck gun (220 rounds)
Various AA guns
|Part of:||8th U-boat Flotilla
(27 January–31 July 1943)
11th U-boat Flotilla
(1 August–31 October 1943)
9th U-boat Flotilla
(1 November 1943–1 October 1944)
33rd U-boat Flotilla
(1 October 1944–16 February 1945)
|Identification codes:||M 49 703|
|Commanders:||Oblt.z.S.. Hans-Gert Mahrholz
(27 January 1943–August 1944)
Oblt.z.S.. Herbert Loeder
(August 1944–16 February 1945)
|Operations:||1st patrol: 13 September–7 November 1943
2nd patrol: 19 December 1943–14 February 1944
3rd patrol: 20–25 June 1944
4th patrol: 28 June–6 July 1944
5th patrol: 12 July–3 August 1944
6th patrol: 29 August–13 October 1944
7th patrol: 15–21 October 1944
8th patrol: 30 January–2 February 1945
9th patrol: 8–16 February 1945
|Victories:||one commercial ship a total loss (7,219 GRT)|
German submarine U-309 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 24 January 1942 at the Flender Werke yard at Lübeck, launched on 5 December 1942, and commissioned on 27 January 1943 under the command of Oberleutnant zur See Hans-Gert Mahrholz. She sailed on nine combat patrols, but damaged only one ship, before being sunk off Scotland on 16 February 1945.
After training with the 8th U-boat Flotilla at Königsberg, U-309 was transferred to the 11th U-boat Flotilla based in Bergen on 1 August 1943, Norway, for front-line service. The U-boat departed Kiel on 26 August, arriving at Bergen seven days later, on 1 September. From there she sailed out into the Norwegian Sea on 13 September, and arrived in Trondheim six days later on the 18th. As U-309 was then reassigned to the 9th U-boat Flotilla based at Brest in France. She left Trondheim on 25 September, and sailed out into the mid-Atlantic to patrol, before arriving at Brest on 7 November. During this patrol, on 30 September, U-309 suffered her only casualty, when Mechanikergefreiter Erich Jungmann was lost overboard while working out on deck.
U-309's next patrol took her from Brest, on 19 December 1943, out into the Atlantic west of Ireland, then back to Bordeaux on 14 February 1944. In April 1944 the U-boat was fitted with a Schnorchel underwater-breathing apparatus.
3rd - 5th patrols
In June and July 1944 U-309 made two short patrols in the Bay of Biscay, before finally achieving success during her fifth patrol. The U-boat sailed from Brest on 12 July 1944 and into the English Channel. There, at 21:00 on 24 July, she fired three LuT pattern-running torpedoes at Convoy FTM-47, en route from Juno Beach in Normandy to Southend, and hit the 7,219 ton British Liberty ship Samneva. Badly damaged, the ship was beached at Southampton, but then broke in two and was declared a total loss. U-309 returned to Brest on 3 August.
6th and 7th patrols
As the French bases fell to the advancing Allies, U-309 was transferred again, this time to the 33rd U-boat Flotilla based at Flensburg. Under her new commander Oberleutnant zur See Herbert Loeder she left La Pallice on 29 August 1944, and sailed around the British Isles to Stavanger, Norway, arriving on 13 October. The U-boat left there after only two days, sailing to Flensburg by the 21st.
8th and 9th patrols
There, on 16 February 1945, U-309 was shadowing Convoy WN-74 into the Moray Firth when she was detected by the Canadian River class frigate Saint John with ASDIC (sonar). The first attack on the U-boat produced some oil on the surface. Two further attacks were carried out using the Hedgehog anti-submarine mortar, which produced more oil. The fourth attack using depth charges produced wreckage including charts, signal books and cork insulation material. U-309 sank in position Coordinates: . All 47 aboard were lost.
The wreck of what is believed to be U-309 was located on 17 May 2001, 25 miles off Wick in 62 metres (203 ft) of water. There are no identifying features, but the Type VIIC U-boat is close to the reported position of U-309's sinking, and the damage sustained is consistent with that caused by depth charges. However there is a possibility that the wreck may be the U-1020, which went missing in the North Sea in November 1944 and has never been found. However, a deck gun mount was found on the wreck, which would rule out the possibility of it being U-1020.
Summary of Raiding Career
|24 July 1944||Samneva||United Kingdom||7,219||Total loss|
- Helgason, Guðmundur. "The Type VIIC boat U-309". uboat.net. Retrieved 11 April 2010.
- Helgason, Guðmundur. "War Patrols by German U-boat U-309". uboat.net. Retrieved 11 April 2010.
- Helgason, Guðmundur. "Patrol of U-boat U-309 from 13 Sep 1943 to 18 Sep 1943". uboat.net. Retrieved 11 April 2010.
- Helgason, Guðmundur. "Patrol of U-boat U-309 from 25 Sep 1943 to 7 Nov 1943". uboat.net. Retrieved 11 April 2010.
- Helgason, Guðmundur. "Patrol of U-boat U-309 from 12 Jul 1944 to 3 Aug 1944". uboat.net. Retrieved 11 April 2010.
- Helgason, Guðmundur. "Samneva (Steam merchant)". uboat.net. Retrieved 11 April 2010.
- "The U-309 Expedition". scapaflow.com. Retrieved 11 April 2010.