O 9-class submarine

HNLMS O 9
Class overview
Name	O 9 class
Builders	Koninklijke Maatschappij De Schelde, Flushing Nederlandsche Scheepsbouw Maatschappij, Amsterdam Fijenoord, Rotterdam
Operators	Royal Netherlands Navy
Preceded by	HNLMS O 8
Succeeded by	O 12 class
Built	1923–1926
In commission	1926–1944
Completed	3
Lost	1
General characteristics
Type	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

The O 9-class submarine consisted of three submarines, built for the Royal Netherlands Navy. Used for patrols in the Dutch home waters. The class comprised O 9, O 10, and O 11. Its diving depth was 60 metres (200 ft).