Check out the LCAC: The massive Navy hovercraft that hauls Marines into battle
The US Navy's Landing Craft, Air Cushion, or LCAC, is designed to haul 60 to 75 tons of cargo over the water and across the beach during amphibious operations.
The LCAC's air cushion allows it to access 70% of the world's coastline, outstripping conventional landing craft, which can only handle about 15%.
The LCAC first deployed aboard the USS Germantown dock-landing ship in 1987 and continues to serve the Navy, hauling everything from personnel and equipment to landing craft and M1 Abrams tanks to shore.
Over the weekend, LCACs aboard amphibious-assault ship USS Bonhomme Richard took part in an amphibious-landing rehearsal as part of Talisman Saber 17, a US-Australian bilateral exercise done every two years off the coast of Australia.
In footage released by the US Defense Department, LCACs can be seen entering and exiting the Bonhomme Richard's well deck and zipping across the water, performing exercises to "increase naval proficiencies in operating against blue-water adversarial threats" during littoral operations.
The Navy has 91 LCACs in service, and a Service Life Extension Program is underway to add 10 years of life to 64 of them by the end of the program in 2018. A contract has already been issued for the LCAC's replacement, the Ship to Shore Connector.
The USS Kearsarge, another of the Navy's amphibious-assault ships, can carry up to three LCACs alongside a full complement of about 2,000 Marines and their gear.
Assault Craft Unit Four, an LCAC on the Kearsarge that Business Insider toured during Fleet Week, can carry up 72 tons and hit speeds close to 60 mph. Fully loaded, it has just a 2-foot-7-inch draft.
Assault Craft Unit Four, which has its own Facebook page, is manned by a crew of 5 and undertakes humanitarian and disaster relief, oil-spill response, and community outreach missions in addition to military operations.
LCACs' propulsion is generally provided by four gas-turbine engines — two propulsion and two lift — with two shrouded pitch propellers. The crafts also have rudders and thrusters for control.
LCACs' armaments typically include .50-caliber machine guns and 40 mm grenade launchers.