HNLMS O 9

O 9 was an O 9-class patrol submarines of the Royal Netherlands Navy. The ship was built by Koninklijke Maatschappij De Schelde shipyard in Flushing.

O 9
History
Netherlands
Name	O 9
Builder	Koninklijke Maatschappij De Schelde, Flushing
Laid down	1 December 1923 or 23 September 1922
Launched	7 April 1925
Commissioned	18 January 1926
Decommissioned	1 December 1944
Fate	Sold for scrap October 1946
General characteristics [1]
Class & type	O 9-class submarine
Displacement	526 tons surfaced 656 tons submerged
Length	54.66 m (179 ft 4 in)
Beam	5.7 m (18 ft 8 in)
Draught	3.53 m (11 ft 7 in)
Propulsion	2 × 450 bhp (336 kW) diesel engines 2 × 250 bhp (186 kW) electric motors
Speed	12 kn (22 km/h; 14 mph) surfaced 8 kn (15 km/h; 9.2 mph) submerged
Range	3,500 nmi (6,500 km; 4,000 mi) at 8 kn (15 km/h; 9.2 mph) on the surface 25 nmi (46 km; 29 mi) at 8 kn (15 km/h; 9.2 mph) submerged
Complement	29
Armament	2 × 21 inch bow torpedo tubes 2 × 17.7 inch bow torpedo tubes 1 × 17.7 inch stern torpedo tube 1 x 88 mm gun 1 x 12.7 mm machine gun

Design

In 1927 a protruding Telefunken radiopeiler was installed on the O 9 that allowed the boat to receive long wave radio frequencies underwater.^[2]

In February 1943 the O 9 was equipped with a fire control system that was developed by its commander Drijfhout van Hooff and manufactured by Cambridge Instrument Company Ltd.^[3]

Service history

The submarine was ordered on 30 August 1921 and laid down in Flushing at the shipyard of Koninklijke Maatschappij De Schelde on 1 December 1923 or 23 September 1922. The launch took place on 7 April 1925. On 18 January 1926 the ship is commissioned in the Dutch navy.^[4]

21 June 1926, O 9, together with O 11, Maarten Harpertszoon Tromp, Jacob van Heemskerck, Z 7 and Z 8, sailed from Den Helder to the Baltic Sea to visit the ports of Kiel, Gothenburg and Trondheim.^[4]

In 1929 O 9, O 10, Jacob van Heemskerck, Z 5, Z 6, made a trip to the Baltic Sea for exercises. The next year on 30 July 1930 O 9, O 10, Jacob van Heemskerck and Witte de With visited Antwerp.^[4]

In 1931 O 9, O 10, O 8, Jacob van Heemskerck, Z 7 and Z 8, made again a trip to the Baltic Sea for exercises. She sailed for the Baltics again in 1936 with her sisters O 10, O 11 and Hertog Hendrik and Z 5. In 1939 O 9 together with her sisters O 10, O 11 were attached to the coastal division. They acted as the offensive part of Dutch coastal defense.^[4]

From 9 to 11 May 1940 she and O 10 are on patrol off the coast of the Netherlands. During the patrol O 9 was attacked by German military airplanes. 12 May 1940 she, O 10 and a tugboat fled to the United Kingdom where they arrived on 15 May 1940.^[4] While in the UK the O 9 was docked regularly for maintenance, which was needed because it was an old submarine.^[5]

During the war she patrolled the English Channel and the Bay of Biscay. From August 1940 to March 1944 O 9 was attached to the 7th Training Flotilla in Rothesay and used as an ASDIC piggy boat. 1 December 1944 O 9 was decommissioned and September 1945 stricken. October 1946 she was sold for scrapping.^[4]