A spy ship or reconnaissance vessel is a dedicated
ship
A ship is a large watercraft, vessel that travels the world's oceans and other Waterway, navigable waterways, carrying cargo or passengers, or in support of specialized missions, such as defense, research and fishing. Ships are generally disti ...
intended to gather
intelligence
Intelligence has been defined in many ways: the capacity for abstraction, logic, understanding, self-awareness, learning, emotional knowledge, reasoning, planning, creativity, critical thinking, and problem-solving. It can be described as t ...
, usually by means of sophisticated
electronic eavesdropping. In a wider sense, any ship intended to gather information could be considered a spy ship.
Spy ships are usually controlled by a nation's
government
A government is the system or group of people governing an organized community, generally a State (polity), state.
In the case of its broad associative definition, government normally consists of legislature, executive (government), execu ...
, due to the high costs and advanced equipment required. They tend to be parts of the nation's
navy
A navy, naval force, military maritime fleet, war navy, or maritime force is the military branch, branch of a nation's armed forces principally designated for naval warfare, naval and amphibious warfare; namely, lake-borne, riverine, littoral z ...
, though they may also be operated by
secret service
A secret service is a government agency, intelligence agency, or the activities of a government agency, concerned with the gathering of intelligence data. The tasks and powers of a secret service can vary greatly from one country to another. For i ...
s.
Naval trawler
Naval trawlers are vessels built along the lines of a fishing trawler but fitted out for naval purposes; they were widely used during the World War I, First and World War II, Second World Wars. Some, known in the Royal Navy as "Admiralty trawlers ...
s masquerade as civilian ships such as
fishing trawler
A fishing trawler is a commercial fishing vessel designed to operate fishing trawls. Trawling is a method of fishing that involves actively dragging or pulling a trawl through the water behind one or more trawlers. Trawls are fishing nets tha ...
s, which could be reasonably expected to remain in a certain area for a long time.
Ships which are used to infiltrate
spies or
special forces
Special forces or special operations forces (SOF) are military units trained to conduct special operations. NATO has defined special operations as "military activities conducted by specially designated, organized, selected, trained and equip ...
are sometimes also called "spy ships".
History
An early version of what would become known as a spy ship is the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
civilian
cargo ship
A cargo ship or freighter is a merchant ship that carries cargo, goods, and materials from one port to another. Thousands of cargo carriers ply the world's List of seas, seas and Ocean, oceans each year, handling the bulk of international trade. ...
, which made frequent voyages to
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
,
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
and the
Philippines
The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...
with cargo and passengers during the 1920s and 1930s.
Starting in 1933 as a station ship she was assigned to monitor internal Japanese Fleet frequencies and direction finder azimuths. She had three intercept operators and one chief radioman supervised by an officer. ''Gold Star'' and ground stations provided significant intelligence before the Japanese attack on Pearl Harbor on 7 December 1941.
[ DOCID: 3362395 - Approved for Release by NSA. on 06-16-2008, FOIA Case #51505 - UNCLASSIFIED See pages 31 & 32.]
Spy ships in the modern sense of being specially built and entirely dedicated to intelligence tasks came into being during the early
Cold War
The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...
, and they are in use by all major powers. Their uses, in addition to listening in on communications and spy on enemy fleet movements, were to monitor
nuclear test
Nuclear weapons tests are experiments carried out to determine the performance of nuclear weapons and the effects of their explosion. Nuclear testing is a sensitive political issue. Governments have often performed tests to signal strength. Bec ...
s and
missile
A missile is an airborne ranged weapon capable of self-propelled flight aided usually by a propellant, jet engine or rocket motor.
Historically, 'missile' referred to any projectile that is thrown, shot or propelled towards a target; this ...
launches (especially of potential
ICBM
An intercontinental ballistic missile (ICBM) is a ballistic missile with a range (aeronautics), range greater than , primarily designed for nuclear weapons delivery (delivering one or more Thermonuclear weapon, thermonuclear warheads). Conven ...
s).
One of the most important functions for both Cold War spy ship fleets, especially in the 1960s, was the gathering of
submarine
A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...
"signatures"the patterns of noise that could often identify the specific type of submarine and were thus valuable in
anti-submarine warfare
Anti-submarine warfare (ASW, or in the older form A/S) is a branch of underwater warfare that uses surface warships, aircraft, submarines, or other platforms, to find, track, and deter, damage, or destroy enemy submarines. Such operations ar ...
. During that era, the United States fielded about 80 vessels, usually classified as "environmental research" craft, while the Soviet Union had around 60 ships, often converted trawlers or
hydrographic research ships.
In the late 1980s, the Soviet
fisheries fleet was known for having equipped many of their thousands of ships with sophisticated
SIGINT
Signals intelligence (SIGINT) is the act and field of intelligence-gathering by interception of ''signals'', whether communications between people (communications intelligence—abbreviated to COMINT) or from electronic signals not directly u ...
and
ELINT
Signals intelligence (SIGINT) is the act and field of intelligence-gathering by interception of ''signals'', whether communications between people (communications intelligence—abbreviated to COMINT) or from electronic signals not directly u ...
equipment, thus functioning as auxiliary spy ships tracking western naval vessels and electronic communications (though their main function remained commercial fishing).
Operation

A spy ship usually stays in
international waters
The terms international waters or transboundary waters apply where any of the following types of bodies of water (or their drainage basins) transcend international boundaries: oceans, large marine ecosystems, enclosed or semi-enclosed region ...
(or at least outside territorial waters), so as to not violate territorial
border
Borders are generally defined as geography, geographical boundaries, imposed either by features such as oceans and terrain, or by polity, political entities such as governments, sovereign states, federated states, and other administrative divisio ...
s. From there, it will use its electronic equipment to
monitor
Monitor or monitor may refer to:
Places
* Monitor, Alberta
* Monitor, Indiana, town in the United States
* Monitor, Kentucky
* Monitor, Oregon, unincorporated community in the United States
* Monitor, Washington
* Monitor, Logan County, Wes ...
sea and air traffic,
radio
Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connec ...
and
radar
Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track ...
frequencies and also try to intercept and
decrypt
In cryptography, encryption (more specifically, encoding) is the process of transforming information in a way that, ideally, only authorized parties can decode. This process converts the original representation of the information, known as plai ...
coded radio or
phone communications. This is mostly done via passive means such as radio receivers or passive
sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects o ...
. Sometimes however, active measures such as radar or sonar may also be used to detect the movement of
aircraft
An aircraft ( aircraft) is a vehicle that is able to flight, fly by gaining support from the Atmosphere of Earth, air. It counters the force of gravity by using either Buoyancy, static lift or the Lift (force), dynamic lift of an airfoil, or, i ...
,
missile
A missile is an airborne ranged weapon capable of self-propelled flight aided usually by a propellant, jet engine or rocket motor.
Historically, 'missile' referred to any projectile that is thrown, shot or propelled towards a target; this ...
s,
ship
A ship is a large watercraft, vessel that travels the world's oceans and other Waterway, navigable waterways, carrying cargo or passengers, or in support of specialized missions, such as defense, research and fishing. Ships are generally disti ...
s or other vehicles or troops. However, this risks revealing the ship's purpose.
As it is located much closer to the
surveilled area than a fixed installation (given a close by
shoreline
A coast (coastline, shoreline, seashore) is the land next to the sea or the line that forms the boundary between the land and the ocean or a lake. Coasts are influenced by the topography of the surrounding landscape and by aquatic erosion, su ...
), the monitoring is usually much more efficient and in some respects better than even that of spy satellites.
Tracking vessels also have some of the capabilities of spy ships, and as they are controlled by their national governments, they are also intermittently used for similar purposes, such as tracking enemy missile tests.
Soviet AGI trawlers
As the United States Navy began deploying
ballistic missile submarine
A ballistic missile submarine is a submarine capable of deploying submarine-launched ballistic missiles (SLBMs) with nuclear warheads. These submarines became a major weapon system in the Cold War because of their nuclear deterrence capabi ...
s in 1960, the Soviet Union attempted to obtain more information about the capabilities of the
UGM-27 Polaris
The UGM-27 Polaris missile was a two-stage solid-fueled nuclear-armed submarine-launched ballistic missile (SLBM). As the United States Navy's first SLBM, it served from 1961 to 1980.
In the mid-1950s the Navy was involved in the Jupiter missi ...
missile and the locations of the submarines capable of launching them. While the Soviet Navy requested more sophisticated ships, they were allocated trawlers (called ''tra-ou-lery'') from the fishing fleet equipped with more sophisticated sensors and communication equipment. Very capable crews were assigned to these trawlers of unremarkable appearance. They were assigned to patrol stations off United States naval bases to photograph and report arrival and departure of United States warships and auxiliaries. Other trawlers of similar appearance would patrol weapons firing ranges used by the United States Navy to observe practice firings of modern weapons and record the acoustic and/or electromagnetic signature of the sonar, search radar, fire-control radar, guidance, and/or command electronics of each weapons system.
The United States Navy officially designated these trawlers as Auxiliary, General Intelligence or AGI, and they were informally known as "tattletales".
An AGI might be assigned to a single patrol station for as long as six months. These ships were not fast enough to keep up with most warships, but they sometimes congregated around
aircraft carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and hangar facilities for supporting, arming, deploying and recovering carrier-based aircraft, shipborne aircraft. Typically it is the ...
s conducting
air operations of the
United States Sixth Fleet
The Sixth Fleet is a numbered fleet of the United States Navy operating as part of United States Naval Forces Europe and Africa. The Sixth Fleet is headquartered at Naval Support Activity Naples, Italy. The officially stated mission of the Sixt ...
in the
Mediterranean
The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...
or
United States Seventh Fleet
The Seventh Fleet is a numbered fleet of the United States Navy. It is headquartered at U.S. Fleet Activities Yokosuka, in Yokosuka, Kanagawa Prefecture, Japan. It is part of the United States Pacific Fleet. At present, it is the largest of the ...
in the western
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...
, or in suspected patrol areas of ballistic missile submarines. After the
Cuban Missile Crisis
The Cuban Missile Crisis, also known as the October Crisis () in Cuba, or the Caribbean Crisis (), was a 13-day confrontation between the governments of the United States and the Soviet Union, when American deployments of Nuclear weapons d ...
, the
Joint Chiefs of Staff
The Joint Chiefs of Staff (JCS) is the body of the most senior uniformed leaders within the United States Department of Defense, which advises the president of the United States, the secretary of defense, the Homeland Security Council and ...
authorized a ''counter AGI program'' for United States
destroyer
In naval terminology, a destroyer is a fast, maneuverable, long-endurance warship intended to escort
larger vessels in a fleet, convoy, or carrier battle group and defend them against a wide range of general threats. They were conceived i ...
s to come alongside the AGIs to push against them, foul their
screws
A screw is an externally helical threaded fastener capable of being tightened or released by a twisting force (torque) to the screw head, head. The most common uses of screws are to hold objects together and there are many forms for a variety ...
with steel nets, and focus high power electromagnetic transmitters to burn out the amplifying circuitry of their electronic sensors. The AGI crews then revealed their ship-handling skills using superior maneuverability to evade the destroyers' intentions. This jousting in international waters continued until signing of the
U.S.–Soviet Incidents at Sea agreement in 1972.
[
In 1972, as the U.S. and U.K. partners started operating radar station ]Cobra Mist
Cobra Mist was the codename for an Anglo-American experimental over-the-horizon radar station at Orford Ness, England. It was known technically as AN/FPS-95 and sometimes referred to as System 441a; a reference to the project as a whole.
Cobra ...
, it garnered attention from many Soviet spy trawlers. A year later, the radar station was shut down due to interference. The source of the interference was never confirmed and some theories still hold Soviet countermeasures responsible.
List of spy ships
* Argentine Navy
The Argentine Navy (ARA; ). This forms the basis for the navy's ship prefix "ARA". is the navy of Argentina. It is one of the three branches of the Armed Forces of the Argentine Republic, together with the Argentine Army, Army and the Argentine ...
**
* Chinese Navy
** Type 813 spy ship
** Type 814A spy ship
** Type 815 spy ship
** Yuan Wang-class tracking ship
The Yuan Wang-class ( ''Yuǎn wàng'') are a line of Chinese tracking ships used for surveillance and communication of launch vehicle rockets and intercontinental ballistic missiles by the People's Liberation Army Strategic Support Force. This ...
* Finnish Navy
The Finnish Navy ( , ) is one of the branches of the Finnish Defence Forces. The navy employs 2,300 people and about 4,300 conscripts are trained each year. Finnish Navy vessels are given the ship prefix "FNS", short for "Finnish Navy ship", but ...
** (Decommissioned)
* French Navy
The French Navy (, , ), informally (, ), is the Navy, maritime arm of the French Armed Forces and one of the four military service branches of History of France, France. It is among the largest and most powerful List of navies, naval forces i ...
**
* German Navy
The German Navy (, ) is part of the unified (Federal Defense), the German Armed Forces. The German Navy was originally known as the ''Bundesmarine'' (Federal Navy) from 1956 to 1995, when ''Deutsche Marine'' (German Navy) became the official ...
**
* Indian Navy
The Indian Navy (IN) (ISO 15919, ISO: ) is the Navy, maritime and Amphibious warfare, amphibious branch of the Indian Armed Forces. The President of India is the Supreme Commander of the Indian Navy. The Chief of the Naval Staff (India), Chief ...
** INS Anvesh
** INS Dhruv
INS ''Dhruv'' (A40) is a research vessel and Tracking ship, missile range instrumentation ship built by India's Hindustan Shipyard, Hindustan Shipyard Limited (HSL). The ship was earlier only known by its shipyard designated yard number as VC-1 ...
*Islamic Republic of Iran Navy
The Islamic Republic of Iran Navy (IRIN; ), also referred as the Iranian Navy (abbreviated NEDAJA; ), is the naval warfare service branch of Iran's regular military, the Islamic Republic of Iran Army, Islamic Republic of Iran Army (''Artesh''). I ...
**IRIS ''Zagros''
* Italian Navy
The Italian Navy (; abbreviated as MM) is one of the four branches of Italian Armed Forces and was formed in 1946 from what remained of the ''Regia Marina'' (Royal Navy) after World War II. , the Italian Navy had a strength of 30,923 active per ...
**
* Royal Norwegian Navy
The Royal Norwegian Navy () is the branch of the Norwegian Armed Forces responsible for navy, naval operations of Norway, including those of the Norwegian Coast Guard. , the Royal Norwegian Navy consists of approximately 3,700 personnel (9,450 i ...
** ''Marjata'' (1992)
** ''Marjata'' (2014)
* Pakistan Navy
The Pakistan Navy (PN) (; ''romanized'': Pākistān Bahrí'a; ) is the naval warfare branch of the Pakistan Armed Forces. The Chief of the Naval Staff, a four-star admiral, commands the navy and is a member of the Joint Chiefs of Staff Com ...
** PNS ''Rizwan''
* Polish Navy
The Polish Navy (; often abbreviated to ) is the Navy, naval military branch , branch of the Polish Armed Forces. The Polish Navy consists of 46 ships and about 12,000 commissioned and enlisted personnel. The traditional ship prefix in the Polish ...
**
**
**
* Russian Navy
The Russian Navy is the Navy, naval arm of the Russian Armed Forces. It has existed in various forms since 1696. Its present iteration was formed in January 1992 when it succeeded the Navy of the Commonwealth of Independent States (which had i ...
** See also: List of active Russian Navy ships#Special-purpose ships
**
**
**
**
**
* Spanish Navy
The Spanish Navy, officially the Armada, is the Navy, maritime branch of the Spanish Armed Forces and one of the oldest active naval forces in the world. The Spanish Navy was responsible for a number of major historic achievements in navigation ...
** ''Alerta''
* Swedish Navy
The Swedish Navy () is the maritime service branch of the Swedish Armed Forces. It is composed of surface and submarine naval units – the Fleet (), formally sometimes referred to as the Royal Navy () – as well as marine units, the Amph ...
**
**
**
* Turkish Navy
The Turkish Naval Forces (), or Turkish Navy (), is the naval warfare service branch of the TAF.
The modern naval traditions and customs of the Turkish Navy can be traced back to 10 July 1920, when it was established as the ''Directorate o ...
**
* Ukrainian Navy
The Ukrainian Navy (), is the Navy, maritime force of Ukraine and one of the eight Military branch, service branches of the Armed Forces of Ukraine.
The naval forces consist of five components: surface forces, submarine forces, Ukrainian Naval ...
** A505 ''Simferopol''
** A512 ''Pereyaslav''
* United States Navy
The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...
**
**
**
**
**
**
**
**
**
**
**
**
See also
* Technical research ship (a class of US spy ships of the early Cold War)
* USS ''Liberty'' incident
* Battle of Amami-Ōshima
The , was a six-hour naval confrontation between Japan and North Korea. It took place near the Japanese island of Amami Ōshima, in the East China Sea on 22 December 2001.
The encounter ended in the sinking of the North Korean vessel, which th ...
References
{{Reflist
Ship types
Espionage techniques
Espionage devices
Signals intelligence