Norwegian B-class submarine

{{Infobox ship image

|Ship image=B-2, B-3 & B-4.jpg

|Ship image size=300px

|Ship caption=The B-class submarines B-2, B-3 and B-4 at quay in Norway

}}

{{Infobox ship class overview

|Name=

|Builders=Karljohansvern Naval shipyard

|Operators={{navy|Norway}}

|Class before=A class

|Class after=U class

|Subclasses=

|Cost=

|Built range=

|In service range= 1923 – 1946

|In commission range=1 February 1923

|Total ships building=

|Total ships planned=

|Total ships completed=6

|Total ships cancelled=

|Total ships active=

|Total ships laid up=

|Total ships lost=1

|Total ships retired=5

|Total ships preserved=

}}

{{Infobox ship characteristics

|Hide header=

|Header caption=

|Ship type=Submarine

|Ship displacement=*365 tons surfaced

• 545 tons submerged

|Ship length={{convert|51|m|ft|abbr=on}}

|Ship beam={{convert|5.3|m|ft|abbr=on}}

|Ship height=

|Ship draught={{convert|3.5|m|ft|abbr=on}}

|Ship draft=

|Ship power=

|Ship propulsion=*2 × Sulzer {{convert|900|shp|kW|abbr=on}} diesel engines

• 2 × {{convert|700|shp|kW|abbr=on}} electric engines

|Ship speed=* {{convert|15|kn|kph|lk=in}} surfaced

• {{convert|8.9|kn|kph}} dived

|Ship range=*{{convert|2,900|nmi|km|lk=in|abbr=on}} at {{convert|9|kn|kph|abbr=on}} surfaced

• {{convert|150|nmi|km|abbr=on}} at {{convert|3|kn|kph|abbr=on}} submerged

|Ship endurance=

|Ship test depth=

|Ship complement=23

|Ship sensors=

|Ship EW=

|Ship armament=*4 × {{convert|45|cm|in|abbr=on}} torpedo tubes

• 1 × {{convert|76|mm|in|abbr=on}} gun

|Ship armour=

|Ship armor=

|Ship notes=

}}