HMS Suva in 1919

An armed boarding steamer (or "armed boarding ship", or "armed boarding vessel") was a merchantman that the British Royal Navy converted to a warship during the First World War. AB steamers or vessels had the role of enforcing wartime blockades by intercepting and boarding foreign vessels. The boarding party would inspect the foreign ship to determine whether to detain the ship and send it into port or permit it to go on its way.


On 28 September 1914 Admiral John Jellicoe, commander-in-chief of the Grand Fleet, sent a telegram in which he pointed out that he did not have enough destroyers available to enforce the blockade. Furthermore, the weather was often too severe for the destroyers. Although Jellicoe did not mention it, after the loss on 22 September of the cruisers HMS Cressy, Aboukir and Hogue, he also did not want large warships making themselves sitting targets for submarines by stopping to examine merchant vessels.[1]

The first request was for 12 vessels, all to be capable of 12–14 knots (22–26 km/h; 14–16 mph), be able to carry enough coal for five days at sea, have wireless, and have boats suitable for boarding parties to use. Each armed boarding steamer was to carry two 3-pounder guns (47 mm/L50) and be under the command of an officer from the Royal Navy. These 12 vessels were requisitioned in October and completed by mid to late-November. Other vessels followed.[1]

The Navy found that cross-Channel passenger vessels were particularly suitable because of their large cargo capacity. As experience with the programme increased, the armed boarding vessels received heavier armament.[1] The Royal Navy realized the need for heavier armament after the German auxiliary cruiser SMS Meteor attacked and sank the armed boarding ship HMS Ramsey on 8 August 1915. The navy wanted to arm the boarding ships with some obsolete 14-inch torpedo tubes, and modern 4-inch (100 mm) guns (possibly the BL 4-inch Mk VII naval gun); Meteor had sunk Ramsey using both a torpedo, and gunfire from two 88 mm (3.5-inch) guns.[a]

The Navy pressed the vessels into other roles. Some carried depth charges for anti-submarine duty while escorting convoys. Still others, particularly in the Mediterranean, served as transports.[citation needed] A quarter were lost during active duty in the war; eight sunk by submarines, one by a German auxiliary cruiser, and one by mines. Two went on to serve again in WWII, with one then being lost to bombing.[citation needed]


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See also


  1. ^ Friedman states that Meteor sank the armed boarding vessel King Orry.[2]


  1. ^ a b c Friedman 2014, p. 62.
  2. ^ Friedman 2014, p. 402.
  3. ^ Tennent 2006, p. 148.
  4. ^ Tennent 2006, p. 69.
  5. ^ Tennent 2006, p. 104.
  6. ^ Tennent 2006, p. 105.
  7. ^ Greenway 2013, p. 101.
  8. ^ Tennent 2006, p. 111.
  9. ^ Helgason, Guðmundur. "Ships hit during WWI: Sarnia". German and Austrian U-boats of World War I - Kaiserliche Marine - Retrieved 17 October 2012.
  10. ^ Tennent 2006, p. 156.
  11. ^ Tennent 2006, p. 138.
  12. ^ Tennent 2006, p. 225.
  13. ^ Tennent 2006, p. 10.


  • Friedman, Norman (2014). Fighting the Great War at Sea: Strategy, Tactic and Technology. Barnsley: Seaforth. ISBN 978-1-59114-188-4.
  • Greenway, Ambros (2013). Cross Channel and Short Sea Ferries: An Illustrated History. Barnsley: Seaforth. ISBN 978-1-84832-170-0.
  • Tennent, AJ (2006). British Merchant Ships Sunk by U-boats in World War One. Penzance: Periscope. ISBN 978-1-904381-36-5.