BYA NEWS

In modern warfare, landing from the sea is an extremely complex form of combat, in which ships capable of transporting amphibious troops ashore are a key step to ensure success.

During World War I and before, navies did not have specialized amphibious ships, amphibious battles were often carried out by using large vessels, transporting troops anchored in the deep waters near the shore, and using small boats to approach the coast. Heavy weapons were also landed in this rather difficult way.

The landing took a lot of time, but more dangerous was that it gave the opponent enough time to counterattack, and the damage of the attacker was immense.

During World War II, due to the advancement of industrial science and shipbuilding technology, a number of specialized amphibious ships and multi-purpose military vessels capable of operating both onshore and on water were born. These ships can directly transport troops, and equip heavy weapons such as tanks landing the shore, amphibious operations were widely applied.

However, this landing method had many limitations, such as landing sites must choose spacious beaches, flat, where reefs or cliffs are not possible. Thus, the enemy could fully predict the landing location and arrange the defensive battlefield.

During the landing at Normandy Beach, the largest scale of World War 2, all four landing sites of the Allies were located in the pre-arranged battlefield of the Germans. Despite relying on absolute overwhelming firepower, the coalition finally managed to break through, but in the first days of the landing, more than 10,000 British and American troops were killed.

After the 1950s of the last century, the development of science and technology created a type of air-cushion vehicle, a very dangerous amphibious vehicle. This hovercraft features high speed, glides on the water, can avoid obstacles and mines underwater. This type of vehicle is also able to cross overshore iron grids and not too high cliffs, thereby expanding the range of coastlines that can be landed.

According to calculations by Western military experts, it can engage amphibious operations on 78% of the world’s shores, compared with 15% for conventional amphibious vessels.

Design

In the 1970s, American war planners launched an ambitious program known as the Landing Craft Air Cushion or LCAC. The US Navy’s air-cushion vehicle was designed to carry 60 to 75 tons of cargo across a vast of waters, to perform any mission appropriate to it.

The first time LCAC was deployed was from the USS Germantown in 1987 and since then, it has performed and completed countless missions. They transport weapons systems, equipment, cargo and personnel of the assault elements of the Marine force both from ship to shore and across the beach.

Basically, LCAC is a high-speed amphibious vessel, with a large payload capacity and a cargo space of 168.1 square meters. As a result, the LCAC can carry up to 180 fully equipped troops or one M-1 Abrams tank. Other basic specifications include a length of 26.4 meters, a width of 14.3 meters and a weight of 182 tons when fully loaded.

The Landing Craft Air Cushion has the advantage of operating both on water and on land. Thanks to the thick air cushion, the vessel can be safely on rugged, muddy ground, on prairies, deserts and marshes, even on frozen seas.

LCAC can maneuver to many combat areas with the fastest speed. The vessels can be transported and launched from all the US amphibious ships featuring a well deck, such as Wasp, Tarawa, Anchorage, and so on.

Propulsion

The craft is operated by a crew of 5. The hull is designed with an air cushion, this air cushion is created from a high-pressure stream of compressed air by the gas turbines, lifting the vessel, pushing it up a few meters from the surface.

When the air compressor was operating, the air was compressed in a circular path around the four bottom of the vessel, spraying under the surface with great pressure. The compression engines, forcing the air vertically down the airbag compartment made of super-durable rubber, keep the craft in a floating state.

To do this, the Landing Craft Air Cushion was equipped with 4 Avco Lycoming TF-40B gas turbines that provide a total of 16,000 shaft horsepower, of which two engines provide propulsion and two for lift. LCAC can reach a maximum speed of 40 knots when fully loaded.

With a fuel capacity of 5000 gallons, the LCAC has a range of 200 nautical miles, which can be increased to 300 nautical miles at a speed of 35 knots.

In the 2001, LCAC service life extension program, these engines were replaced by 4 Vericor Power Systems ETF-40B gas turbines with Full Authority Digital Engine Control. The new engines will provide additional power and lift especially in hot environments, reduce fuel consumption, reduce maintenance needs and reduce lift footprint.

Armament

For self-defense, the LCAC is equipped with two 12.7 mm machine guns,  Mk 19 Mod 3 40mm grenade launcher, or the M60 machine gun. In addition, the craft is also equipped with a global positioning system to provide accurate navigation and positioning.

Operators

A total of 91 LCAC were built, 74 in service of the US Navy, and another 6 are in use by the Japan Maritime Self-Defense Force. Approval for the sale was issued by the US Government on April 8, 1994. The Life Expansion Program will add another 10 years of use to 64 LCAC vessels out of a total of 91. The Americans also had specific plans for the production of new amphibious ships to complement their fleets, when the old ones were replaced.

The largest deployment of these crafts to date includes 11 examples deployed during the Persian Gulf War during the 1991 Desert Storm Campaign. In April 2019, LCACs were mobilized to urgently evacuate US employees from Syria after the situation there became tense.

Currently the US military is still the force with the most air-cushion ships in the world, the price per LCAC was estimated at $41 million in 2015. Although both China and Russia have the capability to produce this vehicle on their own, due to the high cost of production and operation, the number of Chinese and Russian  air-cushion vehicles is meager.