HOME

TheInfoList



OR:

An amphibious assault ship is a type of amphibious warfare ship employed to land and support ground forces on enemy territory by an amphibious assault. The design evolved from
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 converted for use as helicopter carriers (and, as a result, are often mistaken for conventional fixed-wing aircraft carriers). Modern ships support amphibious
landing craft Landing craft are small and medium seagoing watercraft, such as boats and barges, used to convey a landing force (infantry and vehicles) from the sea to the shore during an amphibious assault. The term excludes landing ships, which are larger. Pr ...
, with most designs including a well deck. Coming full circle, some amphibious assault ships also support V/STOL fixed-wing aircraft, now having a secondary role as aircraft carriers. The role of the amphibious assault ship is fundamentally different from that of a standard aircraft carrier: its aviation facilities have the primary role of hosting helicopters to support forces ashore rather than to support strike aircraft. However, some are capable of serving in the sea-control role, embarking aircraft like
Harrier Harrier may refer to: Animals * Harrier (bird), several species of birds * Harrier (dog) Media * Harrier Comics, a defunct British publisher * Space Harrier, a video game series Military * Harrier jump jet, an overview of the Harrier family: ...
or the new F-35B variant of the Lightning II fighters for combat air patrol and helicopters for anti-submarine warfare or operating as a safe base for large numbers of STOVL fighters conducting air support for an expeditionary unit ashore. Most of these ships can also carry or support landing craft, such as air-cushioned landing craft (
hovercraft A hovercraft, also known as an air-cushion vehicle or ACV, is an amphibious Craft (vehicle), craft capable of travelling over land, water, mud, ice, and other surfaces. Hovercraft use blowers to produce a large volume of air below the hull ...
) or LCUs. The largest fleet of these types is operated by the United States Navy, including the dating back to 1989 and the very similar ships that entered service in 2014. Just as an aircraft carrier leads a carrier strike group in the US Navy, an amphibious assault ship leads an expeditionary strike group. Amphibious assault ships are also operated by the Royal Australian Navy, the Brazilian Navy, the Chinese
People's Liberation Army Navy The People's Liberation Army Navy (PLAN; ), also known as the People's Navy, Chinese Navy, or PLA Navy, is the maritime service branch of the People's Liberation Army. The PLAN traces its lineage to naval units fighting during the Chinese ...
, the
Egyptian Navy The Egyptian Navy ( ar, القوات البحرية المصرية, El-Quwwāt el-Bahareya el-Miṣriyya, Egyptian Navy Forces), also known as the Egyptian Naval Force, is the maritime branch of the Egyptian Armed Forces. It is the largest navy ...
, the French Navy, the
Italian Navy "Fatherland and Honour" , patron = , colors = , colors_label = , march = ( is the return of soldiers to their barrack, or sailors to their ship after a ...
, the Republic of Korea Navy (South Korea) and the Spanish Navy. The term amphibious assault ship is often used interchangeably with other ship classifications. It applies to all large-deck amphibious ships such as the landing platform helicopter (LPH), landing helicopter assault (LHA), and landing helicopter dock (LHD).


History


World War II

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 ...
of World War II,
escort carrier The escort carrier or escort aircraft carrier (U.S. hull classification symbol CVE), also called a "jeep carrier" or "baby flattop" in the United States Navy (USN) or "Woolworth Carrier" by the Royal Navy, was a small and slow type of aircraft ...
s would often escort the landing ships and troop carriers during the island-hopping campaign. In this role, they would provide air cover for the troopships as well as fly the first wave of attacks on the beach fortifications in amphibious landing operations. On occasion, they would even escort the large carriers, serving as emergency airstrips and providing fighter cover for their larger sisters while these were busy readying or refueling their own planes. They would also transport aircraft and spare parts from the US to the remote island airstrips. The Imperial Japanese Army had its own special army ships being similar to aircraft carriers of the Imperial Japanese Navy: they were landing craft carriers that carried both landing craft and aircraft, and the plan was to launch the aircraft at the same time as the landing crafts carrying the troops, and to use them for combat air patrol, aerial reconnaissance and
close air support In military tactics, close air support (CAS) is defined as air action such as air strikes by fixed or rotary-winged aircraft against hostile targets near friendly forces and require detailed integration of each air mission with fire and moveme ...
. First, ( or ), completed in 1934 as the world's first purpose-built landing ship, was designed to launch aircraft, but it did not have the facilities for landing. Its successor, the (), completed in 1942, had a full-length flight deck in addition to the floodable well deck, making it more like a full-fledged aircraft carrier. However, the Japanese were already in a state of defeat, and the ship was eventually not used as an aircraft carrier until it was sunk in the fall of 1944. With the deployment of the 8,000-ton ''Shinshū Maru'' and a further refinement, the 9,000-ton ''Akitsu Maru'' (1941), the Japanese amphibious forces had in hand prototypes for all-purpose amphibious ships. Today the U.S. Navy and Marines use this fundamental concept to the exclusion of all others in their LHA and LHD class amphibious assault carriers. In 1937, British and American observers watched ''Shinshū Maru'' at work off Shanghai and immediately recognized a significant development in amphibious warfare. ''Shinshū Maru'' carried landing craft in a well deck that could be flooded, which allowed the landing craft to float free from an open stern gate. The ship could also hold additional craft on davits, but her next most impressive function was an ability to discharge vehicles from a deck-level parking garage directly onto a pier. The ship also carried two catapults for aircraft but did not embark operational seaplanes. She could, however, transport and unload aircraft if necessary, a capability further developed with ''Akitsu Maru'', which even had a short take-off flight deck.


Post-World War II

Despite all the progress that was seen during World War II, there were still fundamental limitations in the types of coastline that were suitable for assault. Beaches had to be relatively free of obstacles, and have the right tidal conditions and the correct slope. However, the development of the helicopter fundamentally changed the equation. The first use of helicopters in an amphibious assault came during the invasion of Egypt during the Suez War in 1956. In this engagement, two British light fleet carriers, and , were converted to perform a battalion-size airborne assault with helicopters. The techniques were developed further by American forces during the Vietnam War and refined during training exercises. The modern amphibious assault can take place at virtually any point of the coast, making defending against them extremely difficult. Most early amphibious assault ships were converted from small aircraft carriers. As well as the two light aircraft carriers converted for use in the Suez War, the Royal Navy converted the carriers and into " commando carriers" during the 1950s. Their sister ship was also converted to a commando carrier in the early 1970s, but was restored to aircraft carrier operations before the end of the 1970s. In the early 1950s the United States Navy and Marine Corps tested the concept of airborne amphibious operations from aircraft carriers. In 1955 the escort carrier was converted to an assault helicopter carrier (CVHA-1), ultimately re-designated LPH-6 in 1959. ''Thetis Bay'' did not fully meet the Marine Corps requirements so three aircraft carriers; , , and , which had greater aircraft capacity, longer range, and higher speed were converted to helicopter carriers as LPH-4, LPH-5, and LPH-8 between 1959 and 1961. They are sometimes referred to as the ''Boxer'' class after the lead ship in the series. These provided a valuable interim during the construction from 1959 to 1970 of the full complement of seven new ships designed specifically for the landing platform helicopter role. Later amphibious assault craft were constructed for the role. The United States Navy constructed the ''Tarawa'' class of five landing helicopter assault ships, which began to enter service from the late 1970s, and the ''Wasp'' class of eight landing helicopter dock ships, the first of which was commissioned in 1989. The United States Navy is also designing a new class of assault ships: the first ship entered service in October 2014. The first British ship to be constructed specifically for the amphibious assault role was , which was commissioned into the Royal Navy in 1998. Other nations have built amphibious assault ships; the French , South Korea's , and Spain's are all currently active, while Australia has two ships based on the Spanish design. Most modern amphibious assault ships have a well deck (docking well), allowing them to launch landing craft in rougher seas than a ship that has to use cranes or a stern ramp. The
US Navy 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 in ...
s differ among these vessels, depending on, among other things, their facilities for aircraft: a modern landing ship dock (LSD) has a helicopter deck, a landing platform dock (LPD) also has a hangar, and a landing helicopter dock (LHD) or landing helicopter assault (LHA) has a full-length flight deck with internal aviation facilities for both rotary and fixed wing craft below deck.


Design

Due to their aircraft carrier heritage, all amphibious assault ships resemble aircraft carriers in design. The flight deck is used to operate attack and utility helicopters for landing troops and supplies and on some ship types also launch and recover fixed wing aircraft such as V/STOL Harrier "jump jet"s to provide air support to landing operations. STOL aircraft such as the North American Rockwell OV-10 Bronco were sometimes deployed on large-deck amphibious assault ships and were able to perform short take-offs and landings without needing catapults or arresting wires, although for safety and clearance reasons landings were most often not permitted.
Landing craft Landing craft are small and medium seagoing watercraft, such as boats and barges, used to convey a landing force (infantry and vehicles) from the sea to the shore during an amphibious assault. The term excludes landing ships, which are larger. Pr ...
are also carried, either on deck-mounted
davit Boat suspended from radial davits; the boat is mechanically lowered Gravity multi-pivot on Scandinavia'' file:Bossoir a gravité.jpg, Gravity Roller Davit file:Davits-starbrd.png, Gravity multi-pivot davit holding rescue vessel on North Sea ferr ...
s, or in an internal well dock (USN: "well deck").


List of types

*Commando carrier ** ''Centaur''-class aircraft carrier (UK) - retired ** HMS ''Hermes'' (R12) (UK) - restored to full carrier, in service with the Indian Navy from 1986 as INS Viraat until 2017 * Landing helicopter assault (LHA) ** (United States) – Retired ** (United States) * Landing helicopter dock (LHD) ** (Australia) ** Type 075 (China) ** ''Juan Carlos I'' (Spain) ** (France and Egypt) ** (United States) ** (Italy) – Under sea trial ** (Turkey) – Under sea trial ** Project 23900 (Russia) – Under construction * Landing platform helicopter (LPH) ** (South Korea) ** (Brazil), formerly HMS ''Ocean'' ** (United States) – Retired


See also

* Amphibious Assault Ship Project * Amphibious assault submarine – theoretical type * Aviation-capable naval vessels * List of amphibious warfare ships *
Mobile offshore base Mobile offshore base (MOB), sometimes called a joint mobile offshore base (JMOB), is a concept for supporting military operations beyond the home shores, where conventional land bases are not available, by deploying on the high seas or in coasta ...


References


Bibliography

* *


External links


In-depth look at various classes
{{Authority control