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
carriers converted for use as helicopter carriers, but includes support for amphibious landing
craft, with most designs including a well deck. Coming full circle, some amphibious
assault ships now have a secondary role as aircraft carriers.
The role of the amphibious assault ship is fundamentally different from 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 fighters for CAP and ASW helicopters
or operating as a safe base for large numbers of STOVL fighters conducting air support for
the MEU once it has gone ashore. Most of these ships can also carry or support landing craft,
such as air-cushioned landing craft or LCUs. The largest fleet of these types is operated
by the United States Navy, including the Tarawa class dating back to the 1970s and the larger
Wasp class ships that debuted in 1989. Amphibious assault ships are also operated by the British
Royal Navy, the French Navy, the Italian Navy, the Republic of Korea Navy, and the Spanish
Navy. Although the term amphibious assault ship
is often used interchangeably with the more-general term amphibious warfare ship, it specifically
applies only to large-deck amphibious ships such as the LPH, LHA, and LHD types. This
does not include the amphibious transport dock, and dock landing ship.
History World War II
In the Pacific theater of World War II, escort carriers 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. In addition, they would also transport
aircraft and spare parts from the US to the remote island airstrips.
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, Ocean and Theseus, 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 Colossus class light aircraft carriers converted for use in the Suez War, the British
Royal Navy converted the Centaur class carriers Albion and Bulwark into "commando carriers"
during the 1950s. Their sister ship HMS Hermes was also converted to a commando carrier in
the early 1970s, but was restored to aircraft carrier operations before the end of the 1970s.
The United States Navy used three Essex class aircraft carriers; Boxer, Princeton, and Valley
Forge, and the Casablanca class escort carrier USS Thetis Bay as the basis of their amphibious
assault fleet, before constructing the five Iwo Jima class ships 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 America class ship is predicted to enter service in 2013.
The first British ship to be constructed specifically for the amphibious assault role was HMS Ocean,
which was commissioned into the Royal Navy in 1998. Other nations have built amphibious
assault ships; the French Mistral class, Italy's San Giorgio class, South Korea's ROKS Dokdo,
and Spain's Juan Carlos I are all currently active, while Australia is building two Canberra
class ships based on the Spanish design. 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 Harrier
Jump Jets to provide air support to landing operations. STOL aircraft such as the OV-10
were sometimes deployed on and were able to perform short take-offs and landings on large
deck amphibious assault ships without needing catapults or arresting wires, although for
safety and clearance reasons, the latter was most often not permitted. Landing craft are
also carried, either on deck-mounted davits, or in an internal well deck.
List of types
Landing Helicopter Assault Tarawa class
America class
Landing Helicopter Dock Wasp class
Mistral class Dokdo class
Juan Carlos I Canberra class
Landing Platform Helicopter Iwo Jima class
HMS Ocean
See also Japanese amphibious assault ship Shinshū
Maru Japanese aircraft carrier Akitsu Maru
Related Vehicles Amphibious assault submarine
Amphibious warfare ship Amphibious transport dock
Dock landing ship
Aircraft carrier Escort carrier
Helicopter carrier
List of amphibious warfare ships Notes
References
External links In-depth look at various classes