title: O-class submarine
text: # O-class submarine
  
  O-class submarine may refer to:
  
  * United States O-class submarine
  * Oberon-class submarine
  * Odin-class submarine
  * Several early submarine classes of the Royal Netherlands Navy:
  
      O 1-class submarine consisting only HNLMS O 1
      O 2-class submarine
      O 6-class submarine consisting only HNLMS O 6
      O 7-class submarine consisting only HNLMS O 7
      O 9-class submarine
      O 12-class submarine
      O 16-class submarine consisting only HNLMS O 16
      O 19-class submarine
      O 21-class submarine
  