hms hms pennant number british submarine group class built launched march far ship royal_navy bear spent majority life attached 4th submarine division based australia kept service following war refitted greater underwater performance final submarine posted australia departing january sold broken scrap august design description hms group class submarines second batch group ordered number boats hull increased diving depth feet increase feet torpedo armament earlier group time group coming service realised external torpedo tubes major problems affected boats external tubes abandoned following class submarine expected use tropical climates boats group equipped order deal increased temperatures service world war commissioned july trials work north_sea mid october sent perth western australia arrival joined 4th submarine division supported depot ship perth carried patrols end war far_east service sank japanese japanese sailing vessel coasters june sank tanker june sister hms sank japanese cargo vessel august carried attack convoy august escorted japanese patrol boat successfully sank army cargo ship sinking credited post war survived war continued service royal_navy class submarines rebuilt greater underwater performance slippery super conversion involved removal deck gun replacement conning tower streamlined fin extra batteries installed control room additional electric motors accommodated cutting pressure hull adding new hull section inserted aft control room diesel engines modified output increased gun armaments external torpedo tubes removed bow submarines bridge incorporated added fin section undergo conversion rejoined 4th submarine flotilla sydney australia operated units june participated news anti submarine exercise coast new_zealand underwent dockyard january april august october final royal_navy submarine station australia departing january 1st australian submarine squadron formed 4th submarine squadron temporarily transferred service boats class construction scrapped newport august
HMS Trump (P333)