HMS K4 beached on Walney Island
|Laid down:||28 June 1915|
|Launched:||13 July 1916|
|Commissioned:||1 January 1917|
|Fate:||Sunk, 31 January 1918|
|Class and type:||K-class submarine|
|Length:||339 ft (103 m)|
|Beam:||26 ft 6 in (8.08 m)|
|Draught:||20 ft 11 in (6.38 m)|
|Complement:||59 (6 officers and 53 ratings)|
Accident 17 November 1917
On 17 November 1917, K4 collided with sister ship K1 during an accident off the Danish coast. The light cruiser Blonde operating with K1 had to make a sharp turn to avoid three units from the 4th Cruiser Squadron. And in the confusion, K4 collided with K1. The crew of K1 were rescued and K1 sunk by the Blonde.
K4 was lost on 31 January 1918 during the night time fleet exercises later known as the Battle of May Island (Operation E.C.1) when she was attached to the 13th Submarine Flotilla. While attempting to avoid a collision with K3, she became the victim of collisions with K6 and K7. She was lost with all hands. The wreck is designated as a protected place under the Protection of Military Remains Act 1986.
- Colledge, J. J.; Warlow, Ben (2006) . Ships of the Royal Navy: The Complete Record of all Fighting Ships of the Royal Navy (Rev. ed.). London: Chatham Publishing. ISBN 978-1-86176-281-8.
- Hutchinson, Robert (2005). Janes Submarines: War Beneath The Waves, from 1776 to the Present Day. HarperCollins. ISBN 0060819006.