HNLMS O 6

O 6 was a unique patrol submarine of the Royal Netherlands Navy for European home waters. The ship was built by De Schelde shipyard in Flushing. The submarines diving depth was 40 metres. HNLMS O 7 was very similar to the O 6 and they are sometimes regarded as one class.

Service history
The submarine was ordered on 8 May 1913 and in May 1914 the O 6 was laid down in Flushing at the shipyard of De Schelde. The launch took place on 10 June 1915.

On 5 December 1916 the ship was commissioned in the navy. During World War I the ship was based in Den Helder.

On 7 Jul 1920 the ship left the port of Flushing for a trip to Norway the ports of Odda, Bergen, Gudvangen among others are visited. The ship returned to Flushing in June 1920.

In June 1923 the O 6 was used by Professor F.A. Vening Meinesz for gravity measurements in the North Sea. In November 1936 O 6 was decommissioned.