HNLMS O 8
History
United Kingdom
Name	HMS H6
Builder	Canadian Vickers, Montreal
Laid down	1914[1]
Launched	12 May 1915[1]
Commissioned	10 June 1915[1]
Fate	Sold to the Netherlands on 4 May 1917
Netherlands
Name	HNLMS O 8
Acquired	4 May 1917[2]
Commissioned	7 May 1917[3]
Fate	Scuttled by Dutch forces following German invasion of the Netherlands during Second World War. Later refloated by Germany on 14 May 1940
Nazi Germany
Name	UD-1
Commissioned	21 November 1940[1]
Decommissioned	23 November 1943[1]
Fate	Scuttled in Kiel Harbour following Allied advance on 3 May 1945[1]
General characteristics (as built)
Class and type	H-class submarine
Displacement	364 long tons (370 t) surfaced 434 long tons (441 t) submerged
Length	150 ft 3 in (45.80 m)
Beam	15 ft 4 in (4.67 m)
Propulsion	1 × 480 hp (358 kW) diesel engine 2 × 620 hp (462 kW) electric motors
Speed	13 knots (24 km/h; 15 mph) surfaced 10 knots (19 km/h; 12 mph) submerged
Range	1,600 nautical miles (3,000 km; 1,800 mi) at 10 knots (19 km/h; 12 mph) surfaced 130 nautical miles (240 km; 150 mi) at 2 knots (3.7 km/h; 2.3 mph) submerged
Complement	22
Armament	4 × 18-inch (450mm) bow torpedo tubes 8 × 18 inch torpedoes
Service record as UD-1[1]
Part of:	1st U-boat Flotilla November 1940 – April 1941 3rd U-boat Flotilla May – August 1941 5th U-boat Flotilla August – December 1941 U-boat Defense School December 1941 – July 1943 5th U-boat Flotilla July – November 1943
Commanders:	K.Kapt. Hermann Rigele[4] 21 November 1940 – 3 May 1941 Kptlt. Friedrich Schäfer[5] 4 May – 2 November 1941 Franz Venier [6] 3 November 1941 – 14 December 1942 Kptlt. Wolfgang Ketelsen[7] 15 December 1942 – 17 May 1943 Oblt.z.S. Friedrich Weidner[8] 18 May – 28 November 1943
Operations:	None
Victories:	None

HMS H6 was a British H-class submarine of the Royal Navy built by Canadian Vickers & Co. during World War I.

History

She was completed on 10 June 1915 and was commissioned by the Royal Navy the same year. However, her service in the Royal Navy was short. On 19 January 1916, she ran aground near the Dutch island of Schiermonnikoog, after which she was interned by the Royal Netherlands Navy. On 4 May 1917, an agreement was reached to sell H6 to the Netherlands.

Dutch service

The Royal Netherlands Navy renamed H6 to HNLMS O 8 and refitted her, with knowledge gained from the interned German submarine UC-8. After UC-8 was bought from Germany O 8 was equipped with UC-8's Zeiss periscope. During maintenance in October 1921, O 8 partly sank in the harbour at Den Helder.^[2] Because only minor damage was sustained, she was repaired and continued in service. In the summer of 1925, O 8 together with the other Dutch vessels HNLMS K XI, HNLMS Jacob van Heemskerck, HNLMS Marten Harpertszoon Tromp, HNLMS Z 3 and HNLMS Z 5 were part of an exercise in the Baltic Sea.

During the German attack on the Netherlands at the start of the Second World War, O 8 was still in Dutch service. At the time she was undergoing maintenance and as a result could not escape during the invasion.^[9] Instead it was decided to scuttle her.^[10]

German service

After the surrender of the Netherlands, the German forces were able raise O 8 and found her almost fully intact.^[11]

Germany took O 8 into service as UD-1 and transferred her from Den Helder to Kiel. In Kiel, she was used as training ship to train crews for the German U-boats. Because of her age, she was decommissioned on 23 November 1943. On 3 May 1945, she was scuttled again in the harbour at Kiel.^[12]