![USS Arleigh Burke (DDG-51) approach](https://upload.wikimedia.org/wikipedia/commons/5/53/USS_Arleigh_Burke_%28DDG-51%29_approach.jpg)
Hull number is a serial identification number given to a
boat
A boat is a watercraft of a large range of types and sizes, but generally smaller than a ship, which is distinguished by its larger size, shape, cargo or passenger capacity, or its ability to carry boats.
Small boats are typically found on inl ...
or
ship
A ship is a large watercraft that travels the world's oceans and other sufficiently deep waterways, carrying cargo or passengers, or in support of specialized missions, such as defense, research, and fishing. Ships are generally distinguished ...
. For the military, a lower number implies an older vessel. For civilian use, the HIN is used to trace the boat's history. The precise usage varies by country and type.
United States usage
Civilian use
For civilian craft manufactured in the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
, the hull number is given to the vessel when it is built and forms part of the hull identification number, which uniquely identifies the vessel and must be permanently affixed to the hull in at least two places. A Hull Identification Number (HIN) is a unique set of 12 characters, similar to the
Vehicle Identification Number
A vehicle identification number (VIN) (also called a chassis number or frame number) is a unique code, including a serial number, used by the automotive industry to identify individual motor vehicles, towed vehicles, motorcycles, scooters ...
which is found on automobiles. In 1972, The
United States Coast Guard
The United States Coast Guard (USCG) is the maritime security, search and rescue, and law enforcement service branch of the United States Armed Forces and one of the country's eight uniformed services. The service is a maritime, military, mult ...
was asked to create a standardized format for HINs to allow for better tracking of accidents and history of boats. This HIN format is as follows: The first three characters consist of the Manufacturers Index Code (MIC) and should only be letters. The following five characters are the unique serial number assigned by the Manufacturer, and can be a series of letters and/or numbers with the exception of the letters O, I, and Q (they can be easily mistaken). The last four characters determine the model and certification year of the boat. The HIN may be found on the aft of the vessel in the uppermost right corner. Also, the HIN may be stated on the title, registration, and insurance documents.
United States military
The
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...
, United States Coast Guard, and United States
National Oceanic and Atmospheric Administration
The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditio ...
employ hull numbers in conjunction with a
hull classification symbol
The United States Navy, United States Coast Guard, and United States National Oceanic and Atmospheric Administration (NOAA) use a hull classification symbol (sometimes called hull code or hull number) to identify their ships by type and by ind ...
to uniquely identify vessels and to aid identification. A particular combination of hull classification and hull number is never reused and therefore provides a means to uniquely identify a particular ship. For example, there have been at least eight vessels named , but CV-6 uniquely identifies the
World War II aircraft carrier from all others. For convenience, the combined designation, which is painted on the sides of the hulls, is frequently called the "hull number".
The official Navy Style Guide says that hull numbers do not include hyphens.
The U.S. Navy sometimes ignores the sequence of hull numbering. For example, the Navy built the last
nuclear submarine
A nuclear submarine is a submarine powered by a nuclear reactor, but not necessarily nuclear-armed. Nuclear submarines have considerable performance advantages over "conventional" (typically diesel-electric) submarines. Nuclear propulsion, ...
as . Next the Navy built the three
''Seawolf''-class submarines SSN-21 through SSN-23. Then the Navy later resumed the original sequence of hull numbers with for its next class of nuclear
attack submarine
An attack submarine or hunter-killer submarine is a submarine specifically designed for the purpose of attacking and sinking other submarines, surface combatants and merchant vessels. In the Soviet and Russian navies they were and are called ...
s.
This change in numbering was done because the ''Seawolf'' class was to have a radical new and large design for the continuation of the
Cold War
The Cold War is a term commonly used to refer to a period of geopolitical tension between the United States and the Soviet Union and their respective allies, the Western Bloc and the Eastern Bloc. The term '' cold war'' is used because the ...
into the
21st century
The 21st (twenty-first) century is the current century in the ''Anno Domini'' era or Common Era, under the Gregorian calendar. It began on 1 January 2001 ( MMI) and will end on 31 December 2100 ( MMC).
Marking the beginning of the 21st centur ...
, but cost overruns combined with the end of the
Cold War
The Cold War is a term commonly used to refer to a period of geopolitical tension between the United States and the Soviet Union and their respective allies, the Western Bloc and the Eastern Bloc. The term '' cold war'' is used because the ...
, and the resulting reduction of the Navy's construction budget resulted in only three of these boats being constructed: , , and .
Also, whenever
warship
A warship or combatant ship is a naval ship that is built and primarily intended for naval warfare. Usually they belong to the armed forces of a state. As well as being armed, warships are designed to withstand damage and are usually faster a ...
s are constructed in American shipyards for foreign navies, any hull numbers used to identify the ships during their construction are never reused by the U.S. Navy. For example, the
guided missile destroyer
A guided-missile destroyer (DDG) is a destroyer whose primary armament is guided missiles so they can provide anti-aircraft warfare screening for the fleet. The NATO standard designation for these vessels is DDG, while destroyers who have a prim ...
s that were built for the
Royal Australian Navy
The Royal Australian Navy (RAN) is the principal naval force of the Australian Defence Force (ADF). The professional head of the RAN is Chief of Navy (CN) Vice Admiral Mark Hammond AM, RAN. CN is also jointly responsible to the Minister of ...
in
Bay City, Michigan
Bay City is a city and county seat of Bay County in the U.S. state of Michigan, located near the base of the Saginaw Bay on Lake Huron. As of the 2010 census, the city's population was 34,932, and it is the principal city of the Bay City Metropol ...
were given the hull numbers DDG-25, DDG-26, and DDG-27; but these hull numbers were not assigned to any American
destroyer
In naval terminology, a destroyer is a fast, manoeuvrable, long-endurance warship intended to escort
larger vessels in a fleet, convoy or battle group and defend them against powerful short range attackers. They were originally developed in ...
s after the Australian Navy had changed those to its own identification numbers.
Several other new warships have been constructed in American shipyards for countries such as
West Germany
West Germany is the colloquial term used to indicate the Federal Republic of Germany (FRG; german: Bundesrepublik Deutschland , BRD) between its formation on 23 May 1949 and the German reunification through the accession of East Germany on 3 O ...
and
Taiwan
Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the nort ...
. Guided-missile frigates were constructed in
Portugal
Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...
under military-assistance aid packages were given the hull numbers DEG 7 through 11.
When a naval vessel is modified for use as a different type of ship, it is often assigned a new hull number along with its new classification. Often the actual number remains the same while the hull classification changes. For example, a
heavy cruiser
The heavy cruiser was a type of cruiser, a naval warship designed for long range and high speed, armed generally with naval guns of roughly 203 mm (8 inches) in caliber, whose design parameters were dictated by the Washington Naval Tr ...
(CA) that was converted into a
guided missile cruiser
A cruiser is a type of warship. Modern cruisers are generally the largest ships in a fleet after aircraft carriers and amphibious assault ships, and can usually perform several roles.
The term "cruiser", which has been in use for several hu ...
became a CG and its number was changed. This happened with , , and , which became, respectively, CG-10, CG-11, and CG-12.
Also, during
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
, nine ''Cleveland''-class
light cruiser
A light cruiser is a type of small or medium-sized warship. The term is a shortening of the phrase "light armored cruiser", describing a small ship that carried armor in the same way as an armored cruiser: a protective belt and deck. Prior to thi ...
s (CL) were converted to light
aircraft carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a ...
s (CVL), with different numbers.
During the 1970s, the
guided missile frigates that were then redesignated as guided missile cruisers had their designations changed from DLG to CG; in this case, they kept their previous numbers. Some other guided-missile frigates were redesignated as guided missile destroyers (DDG) and given new numbers.
Hull numbers have been used to identify armored
tank
A tank is an armoured fighting vehicle intended as a primary offensive weapon in front-line ground combat. Tank designs are a balance of heavy firepower, strong armour, and good battlefield mobility provided by tracks and a powerful engin ...
s for the
U.S. Army
The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cl ...
and the
U.S. Marine Corps, and other military services, also.
European usage
In Europe, ships are given a Craft Identification Number (CIN) or Hull Identification Number (HIN), standardised as EN ISO 10087:2006. The numbers are a permanent, unique, fourteen-digit alphanumeric identifier issued to all marine vessels in Europe. The numbering system is mandated by the European
Recreational Craft Directive
The Recreational Craft Directive, Directive 2013/53/EU, originally Directive 94/25/EC on recreational craft amended by Directive 2003/44/EC, is a European Union directive which sets out minimum technical, safety and environmental standards for b ...
and descended from the American system. Larger vessels over 300
gross tons
Gross tonnage (GT, G.T. or gt) is a nonlinear measure of a ship's overall internal volume. Gross tonnage is different from gross register tonnage. Neither gross tonnage nor gross register tonnage should be confused with measures of mass or weig ...
also receive a permanent international
IMO ship identification number
The IMO number of the International Maritime Organization is a generic term covering two distinct meanings. The IMO ship identification number, is a type of hull number used as a unique ship identifier, and the IMO company and registered owne ...
, and European vessels over 20 metres receive a permanent
ENI number
An ENI number (European Number of Identification or European Vessel Identification Number) is a registration for ships capable of navigating on inland European waters. It is a unique, eight-digit identifier that is attached to a hull for its enti ...
.
An example CID/HIN might appear as "GB-ABC00042-A8-99", where "GB" is the
ISO 3166-1
ISO 3166-1 (''Codes for the representation of names of countries and their subdivisions – Part 1: Country codes'') is a standard defining codes for the names of countries, dependent territories, and special areas of geographical interest. It ...
country code, "ABC" would be the Acme Boat Company's Manufacturer Identity Code (MIC); "00042" would be the forty-second hull constructed by the organisation; "A8" would be January 1998 for the date
keel was laid to the nearest month and "99" denoted as the year 1999 as the particular model year.
Months are denoted from A…L for January…December.
In the United Kingdom, the
British Marine Federation
British Marine is the trade association for the UK leisure, superyacht and small commercial marine industry, currently representing 12 regional associations, 16 Group Associations and 1600+ members across the UK marine supply chain. These include ...
manage the issuing of Manufacturer Identity Code on behalf of the British
Department for Business Innovation and Skills
, type = Department
, logo = Department for Business, Innovation and Skills logo.svg
, logo_width = 200px
, logo_caption =
, picture = File:Лондан. 2014. Жнівень 26.JPG
, seal =
, se ...
.
Amateur
boat builders in the United Kingdom may apply for one-off HIN from the
Royal Yacht Association who will issue one number from their "GB-RYAxxxxx" range.
Russia
![KamAZ military tank transporter](https://upload.wikimedia.org/wikipedia/commons/0/0a/KamAZ_military_tank_transporter.jpg)
The hull number in Russian is known as ''bortovoi nomer''. During the
2014 Russian invasion of Ukraine all hull numbers were painted over in order to conceal presence of the Russian regular army troops in Ukraine.
See also
*
Pennant number
In the Royal Navy and other navies of Europe and the Commonwealth of Nations, ships are identified by pennant number (an internationalisation of ''pendant number'', which it was called before 1948). Historically, naval ships flew a flag that iden ...
*
Tail number
References
{{reflist
* United States Code of Federal Regulations, Title 33.
USS Enterprise (CV-6) websiteHIN decoder and Verification Tool for Civilian Use
Ship identification numbers