An armed merchantman is a
In more modern times, auxiliary cruisers were used offensively as merchant raiders to disrupt trade chiefly during both World War I and World War II, particularly by Germany.
While armed merchantmen are clearly inferior to purpose-built warships, sometimes they have scored successes in combat against them. Examples include East Indiamen mimicking ships of the line and chasing off regular French warships in the Battle of Pulo Aura in 1804, and the German auxiliary cruiser Kormoran sinking the Australian light cruiser HMAS Sydney in their battle in 1941, although Kormoran was also destroyed and had to be scuttled.
East Indiamen of various European countries were heavily armed for their long journeys to the
Development of auxiliary cruisers
In 1856, privateering (or seizure of a belligerent country's merchant ships as a private enterprise) lost international sanction under the
Russia purchased three ships in 1878 of 6,000 long tons (6,100 t) armed with 6-inch (150 mm) guns for use as auxiliary cruisers for a Russian Volunteer Fleet. Germany and the United Kingdom responded to the precedent by asking their shipping companies to design fast steamers with provision for mounting guns in time of war.
In 1890 German and British shipyards built new civilian ships designed for wartime conversion, and
In 1895 the Imperial German Navy mobilized the provisional auxiliary cruiser Normannia for a 15-day trial armed with eight 6-inch guns, two 3.5-inch (89 mm) guns, six 37-millimetre (1.46 in) guns, and two torpedo boats.
In both World Wars, both Germany and the United Kingdom used auxiliary cruisers. While the British used armed passenger liners defensively for protecting their shipping, the German approach was to use them offensively to attack enemy shipping.
Armed merchant cruisers
The armed merchant cruisers (AMC) of the British Royal Navy were employed for convoy protection against enemy warships. They ultimately proved to have limited value and many, particularly ocean liners, were later converted into troopships, a role for which they were more suited. Documentary evidence quoted by the BBC researched from the early stages of the First World War suggests that the express liners had greater speed than most warships (few warships of the period could exceed 21 knots), which made them suitable as AMCs. The downside proved to be their high fuel consumption; using them in a purely AMC role would have burned through the Admiralty reserve supplies of steam coal in less than three months. The ships were vulnerable to enemy fire because they lacked warship armour, and they used local control of guns rather than director fire-control systems, which reduced their effective fire power.
A famous AMC of World War I was the British RMS Carmania which, after a battle that caused heavy damage on both sides, sank the German auxiliary cruiser SMS Cap Trafalgar near the Brazilian island of Trinidade in 1914. By coincidence, Cap Trafalgar was disguised as Carmania. In World War II, HMS Jervis Bay, the sole escort for convoy HX 84 in November 1940, stood off the pocket battleship Admiral Scheer, when the German ship attacked the convoy. Though she and five vessels of the convoy were sunk, this enabled the rest of the convoy to escape. Her master, Acting Captain Edward Fegen was awarded the Victoria Cross posthumously for his actions. Another famous action involving an armed merchant cruiser was the November 1939 battle between HMS Rawalpindi and the German battlecruisers Scharnhorst and Gneisenau. Outgunned, the Rawalpindi was quickly sunk.
The German practice was to arm merchantmen with hidden weapons and use them as
In World War II, Nazi Germany's Kriegsmarine operated ten very successful auxiliary cruisers, ranging in tonnage from 3,860 to 9,400; typically these vessels were equipped with:
- Observation seaplanes
- 15 cm (6 in) guns
- Smaller armaments (typically hidden away behind specially designed and hinged bulwarks, or beneath fake deckhouses and/or skylights)
To preserve their cover, these ships flew the flags of neutral or occasionally Allied nations. They were refueled and provisioned from special supply ships, from Japanese island bases or from
In one incident, the German Kormoran (ex-merchantman Steiermark) managed to surprise and sink the Australian light cruiser HMAS Sydney, which approached too close, though Kormoran was also sunk in the engagement. This was the only occasion in history when an armed merchantman managed to sink a modern warship; in most cases, auxiliary cruiser raiders tried to avoid confrontation with warships. Kormoran's attack upon Sydney was motivated by desperation. She was not the most successful German raider of World War II (both Atlantis and Pinguin scored higher kill tonnages). Another, Stier, was also sunk in a mutually destructive engagement with the American Liberty ship SS Stephen Hopkins.
The only encounters between Allied and Axis auxiliary cruisers in World War II were all with the raider
The CAM ship (from catapult armed merchantman) was a British merchantman fitted with a catapult that could launch, but not recover, a single fighter aircraft.
The merchant aircraft carrier or "MAC" was a British or Dutch cargo ship with a flight deck that could carry a small number of aircraft.
Despite a rise in
In 2007, facing a chronic shortage of naval vessels the Cuban Navy placed into service the Rio Damuji class of frigates, which are large fishing trawlers converted into warships.
In April 2010, it was reported that a Russian company was offering a version of the
Since the late 19th century various navies have used armed merchant ships in the role of auxiliary cruisers, also called armed merchant cruisers. Significant use of this type of ship was made by Britain and Germany in both World Wars.
Some of the ships used in this role include:
- SS Saint Paul (1895) – Saint Paul SP-1643 – Spanish–American War (United States)
- Shinano Maru – Russo-Japanese War (Japan)
- Ural– Russo-Japanese War (Russia)
- Berrima – World War I (Australia)
- Cap Trafalgar – World War I (Germany)
- Olympic – World War I (Great Britain)
- Mar Negro – Spanish Civil War (Nationalist Spain)
- Kormoran – World War II (Germany)
- Thor – World War II (Germany)
- Jervis Bay – World War II (Great Britain)
- Rawalpindi – World War II (Great Britain)
- Ramb I– World War II (Italy)
- Aikoku Maru – World War II (Japan)
- Prince David– World War II (Canada)
- Armed merchant ship
- Defensively equipped merchant ship
- False flag
- Hired armed vessels
- List of auxiliary and merchant cruisers
- Merchant raider
- "Carmania I". Archived from the original on 2006-10-20. Retrieved 2006-07-21.
- PNTL Fleet Archived 2011-06-14 at the Wayback Machine
- "Nuclear fuel ship docks in Japan". BBC. 27 September 1999. Retrieved 2008-08-27.
- Brown, Paul (20 January 1999). "Nuclear fuel ships to be armed with heavy guns". The Guardian. Retrieved 2008-08-27.
- "UK British nuclear fuel ships armed". BBC. 8 July 1999. Retrieved 2008-08-27.
- "Arming Container Ships With Anti-Ship Missiles". StrategyPage. April 14, 2010.
- "Somali piracy: Armed guards to protect UK ships". BBC News Online. 30 October 2011.