![Sirius refueling Juneau](https://upload.wikimedia.org/wikipedia/commons/7/74/Sirius_refueling_Juneau.jpg)
A replenishment oiler or replenishment tanker is a naval
auxiliary ship
An auxiliary ship is a naval ship designed to support combatant ships and other naval operations. Auxiliary ships are not primary combatant vessels, though they may have some limited combat capacity, usually for purposes of self-defense.
Auxil ...
with
fuel tank
A fuel tank (also called a petrol tank or gas tank) is a safe container for flammable fluids. Though any storage tank for fuel may be so called, the term is typically applied to part of an engine system in which the fuel is stored and propel ...
s and dry
cargo hold
120px, View of the hold of a container ship
A ship's hold or cargo hold is a space for carrying cargo in the ship's compartment.
Description
Cargo in holds may be either packaged in crates, bales, etc., or unpackaged (bulk cargo). Access to ho ...
s which can supply both fuel and dry stores during
underway replenishment
Replenishment at sea (RAS) (North Atlantic Treaty Organization/Commonwealth of Nations) or underway replenishment (UNREP) (U.S. Navy) is a method of transferring fuel, munitions, and stores from one ship to another while under way. First develope ...
(UNREP) at sea. Many countries have used replenishment oilers.
The
United States Navy's hull classification symbol for this type of ship was AOR. Replenishment oilers are slower and carry fewer dry stores than the U.S. Navy's modern
fast combat support ship
The fast combat support ship (US Navy hull classification symbol: AOE) is the United States Navy's largest combat logistics ship, designed as an oiler, ammunition and supply ship. All fast combat support ships currently in service are operated ...
s, which carry the classification AOE.
History
![RFA Tiderace Dual RAS with HMS Lancaster and HMS Westminster](https://upload.wikimedia.org/wikipedia/commons/2/24/RFA_Tiderace_Dual_RAS_with_HMS_Lancaster_and_HMS_Westminster.jpg)
The development of the "oiler" paralleled the change from coal- to oil-fired boilers in warships. Prior to the adoption of oil fired machinery, navies could extend the range of their ships either by maintaining
coaling station
Fuelling stations, also known as coaling stations, are repositories of fuel (initially coal and later oil) that have been located to service commercial and naval vessels. Today, the term "coaling station" can also refer to coal storage and feedin ...
s or for warships to raft together with
colliers and for coal to be manhandled aboard. Though arguments related to fuel security were made against such a change, the ease with which liquid fuel could be transferred led in part to its adoption by navies worldwide.
One of the first generation of "blue-water" navy oiler support vessels was the British RFA ''Kharki'', active 1911 in the run-up to the
First World War
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
. Such vessels heralded the transition from coal to oil as the fuel of
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 and removed the need to rely on, and operate within range of coaling stations. During the
Second World War
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 ...
, the United States Navy's dramatically enlarged fleets, especially those in the
Pacific Theater
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
, required massive quantities of black oil,
diesel oil
Diesel fuel , also called diesel oil, is any liquid fuel specifically designed for use in a diesel engine, a type of internal combustion engine in which fuel ignition takes place without a spark as a result of compression of the inlet air and t ...
,
avgas
Avgas (aviation gasoline, also known as aviation spirit in the UK) is an aviation fuel used in aircraft with spark-ignited internal combustion engines. ''Avgas'' is distinguished from conventional gasoline (petrol) used in motor vehicles, w ...
, and other fuels and lubricants to support American land, sea, and air operations against remote, widely dispersed Japanese forces. Those supply demands resulted in U.S. Navy personnel refining many established practices for oilers and creating new procedures for replenishing warships while
underway
Underway, or under way, is a nautical term describing the state of a vessel. "Way" arises when there is sufficient water flow past the rudder of a vessel that it can be steered. A vessel is said to be underway if it meets the following criteria: ...
and for transporting highly combustible materials with increased effectiveness through hostile waters and over vast ocean distances.
Modern examples of the
fast combat support ship
The fast combat support ship (US Navy hull classification symbol: AOE) is the United States Navy's largest combat logistics ship, designed as an oiler, ammunition and supply ship. All fast combat support ships currently in service are operated ...
include the large British Fort class, displacing and measuring in length and the United States' , which displaces and has an
overall length
The overall length (OAL) of an ammunition cartridge is a measurement from the base of the brass shell casing to the tip of the bullet, seated into the brass casing. Cartridge overall length, or "COL", is important to safe functioning of reloads i ...
of .
Characteristics
![Wabash Refueling Midway 1974](https://upload.wikimedia.org/wikipedia/commons/7/73/Wabash_Refueling_Midway_1974.jpg)
For all but the largest navies, replenishment oilers are typically one of the largest ships in the fleet. Such ships are designed to carry large amounts of fuel and dry stores for the support of naval operations far away from port. Replenishment oilers are also equipped with more extensive medical and dental facilities than smaller ships can provide.
Such ships are equipped with multiple refueling gantries to refuel and resupply multiple ships at a time. The process of refueling and supplying ships at sea is called
underway replenishment
Replenishment at sea (RAS) (North Atlantic Treaty Organization/Commonwealth of Nations) or underway replenishment (UNREP) (U.S. Navy) is a method of transferring fuel, munitions, and stores from one ship to another while under way. First develope ...
. Furthermore, such ships often are designed with helicopter decks and hangars. This allows the operation of rotary-wing aircraft, which allows the resupply of ships by helicopter. This process is called
vertical replenishment
Vertical replenishment, or VERTREP, is a method of supply of seaborne vessels by helicopter. The United States Department of Defense defines VERTREP as:
...the transfer of cargo between ships using helicopters. VERTREP is often used to supplement ...
. These ships, when operating in concert with surface groups, can act as an aviation maintenance platform where helicopters receive more extensive maintenance than can be provided by the smaller hangars of the escorting ships.
Their size, additional facilities, and ability to support the operation of other vessels, means that replenishment oilers have been used as
command ship
Command ships serve as the flagships of the commander of a fleet. They provide communications, office space, and accommodations for a fleet commander and their staff, and serve to coordinate fleet activities.
An auxiliary command ship features ...
s, with some ships, such as the French , this capability being built into the vessels from the start.
Armament
Because the replenishment oiler is not a combat unit, but rather a support vessel, such ships are often lightly armed, usually with self-defense systems (such as the
Phalanx CIWS
The Phalanx CIWS (often spoken as "sea-wiz") is a gun-based close-in weapon system to defend military watercraft automatically against incoming threats such as aircraft, missiles, and small boats. It was designed and manufactured by the Gene ...
close-in weapons systems), small arms, machine guns and/or light automatic cannons. They may also carry
man-portable air-defense systems
Man-portable air-defense systems (MANPADS or MPADS) are portable surface-to-air missiles. They are guided weapons and are a threat to low-flying aircraft, especially helicopters.
Overview
MANPADS were developed in the 1950s to provide military ...
for additional air defense capability.
Operators
* operates a single purchased from France.
* operates
HMAS ''Sirius'' and
HMAS ''Supply''
* operates the
''Almirante Gastão Motta''
* operates the .
* operates a single purchased from the United States, and the
''Araucano''.
* operates two
''Fuyu''-class fast combat support ships, four
''Dayun''-class general stores issue ships, nine
''Fuchi''-class replenishment ships, and a single
''Fusu''-class replenishment ship.
* operates the
ROCS ''Wu Yi'' and
ROCS ''Panshih''
* operates two s, purchased from Germany.
* operates a single , purchased from Germany.
* operates three s
* operates six s, two s, and three s.
* operates a single and two s, purchased from Germany.
* operates two s, one , and a single .
* operates a single purchased from the United Kingdom, two ''Tarakan''-class tankers and more on order.
* operates a single and two s.
* operates two s.
* operates three s and two s.
* operates three s, and the
ROKS ''Soyang''
* operates
HNLMS ''Karel Doorman''
* operates
HMNZS ''Aotearoa''.
* operates
HNoMS ''Maud''.
* operates a single
''Fuqing''-class replenishment tanker and the
PNS ''Moawin''
* operates the
BAP ''Tacna''
* operates the
ORP ''Bałtyk''
* operates three s, one ''Dora''-class tanker, two ''Uda''-class tankers, one ''Iman''-class tanker, four ''Altay''-class tankers, three ''Dubna''-class tankers, two ''Kaliningradneft''-class tankers, and a single
Project 23130 replenishment oiler
Project 23130 is a series of medium-size replenishment oilers developed by the Spetssudoproect JSC and built by Nevsky Shipyard for the Russian Navy. Initially, it was to be limited only by one vessel, ''Akademik Pashin'', however in January 20 ...
.
* operates two s.
* operates the
* operates the and .
* operates the
HTMS Similan
HTMS ''Similan'' (871) ( th, เรือหลวงสิมิลัน) is a replenishment oiler (AOR) of the Royal Thai Navy. She was intended to support the aircraft carrier and its escorts. ''Similan'' was constructed in the People's Repu ...
* operates two s.
*
Royal Fleet Auxiliary
The Royal Fleet Auxiliary (RFA) is a naval auxiliary fleet owned by the UK's Ministry of Defence. It provides logistical and operational support to the Royal Navy and Royal Marines. The RFA ensures the Royal Navy is supplied and supported by ...
operates one ,two s, and four s.
*
United States Military Sealift Command
Military Sealift Command (MSC) is an organization that controls the replenishment and military transport ships of the United States Navy. Military Sealift Command has the responsibility for providing sealift and ocean transportation for all US m ...
operates 15 s, 14 s, and two s.
* operates a single purchased from Germany
* operates the
RBNV ''Ciudad Bolívar''
Former operators
* decommissioned
BRP ''Lake Caliraya'' in 2020.
* decommissioned
NRP ''Bérrio'' in 2020.
* decommissioned its only in 2001.
United States Navy oilers
![USNS Big Horn](https://upload.wikimedia.org/wikipedia/commons/8/85/USNS_Big_Horn.jpg)
In 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 ...
, an Oiler is a Combat Logistics ship that replenishes other ships with fuel and in some cases food, mail, ammunition and other necessities while at sea, in a process called
Underway Replenishment
Replenishment at sea (RAS) (North Atlantic Treaty Organization/Commonwealth of Nations) or underway replenishment (UNREP) (U.S. Navy) is a method of transferring fuel, munitions, and stores from one ship to another while under way. First develope ...
or UNREP. Up through the
Second World War
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 ...
Navy oilers used commercial tanker hulls, with the addition of UNREP gear, defensive guns, and military electronic and damage-control equipment; since the 1950s however they have been built from the keel up as specialized naval auxiliaries. They were previously classified as Fleet Oilers
in the 20th Century; under the current
MSC operation their full classification is listed as Fleet Replenishment Oilers.
Since the 1960s the classification Transport Oiler (AOT) has applied to tankers which ship petroleum products to depots around the world, but do not engage in UNREP.
The first fleet oilers
were identified by the hull designation AO, which is still in use.
Large, fast multifunction oilers which also provide ammunition and dry stores are identified as
Fast Combat Support Ship
The fast combat support ship (US Navy hull classification symbol: AOE) is the United States Navy's largest combat logistics ship, designed as an oiler, ammunition and supply ship. All fast combat support ships currently in service are operated ...
s (AOE),
and mid-size ones Replenishment Oilers (AOR). The AOR designation is no longer in use. All of these oilers provide the combined services of the AO, AE, AFS and AK.
The style "USNS" and prefix "T" identify a ship as being operated by a civilian crew under the
Military Sealift Command
Military Sealift Command (MSC) is an organization that controls the replenishment and military transport ships of the United States Navy. Military Sealift Command has the responsibility for providing sealift and ocean transportation for all US m ...
(known as the
Military Sea Transportation Service
Military Sealift Command (MSC) is an organization that controls the replenishment and military transport ships of the United States Navy. Military Sealift Command has the responsibility for providing sealift and ocean transportation for all US m ...
until 1970).
Current classes
There are three classes of vessels currently in commissioned service:
*
''Henry J. Kaiser'' class
*
''John Lewis'' class
*
''Supply'' class
Both the Henry J. Kaiser-class and Supply class will be replaced by the John Lewis-class ships.
References
External links
DANFS USS KALAMAZOO (AOR-6) websiteUS Naval Vessel RegisterKMS DithmarschenSpanish Navy Patino Class AORHMAS Success, AOR-304
{{MARCOMships
Ship types