 She was launched on 23 December 1911.She initially received the pennant number of "H 2", but was assigned the number "3" in April 1913.In September 1914, "Havmanden", displaying her pennant number of "3" on her conning tower, was mistaken for the German U-boat by the British submarine , but "Havmanden" escaped without damage when "E11"s torpedo missed its mark.