Like other conventional landing craft, the LCU design dates back to the 1940s. The idea behind the LCU was simple. Take the largest possible cargo/vehicle load possible, deliver it to and from a hostile shore, and then return to a mother ship-usually one of the first-generation LSDs. The LCU can carry up to 180 tons of vehicles, troops, and cargo at speeds approaching 12 kt/22 kph in virtually any seastate or weather, and deliver them to a 'hot' shoreline. It is a big, brutish sort of craft, with none of the LCAC's futuristic look. In fact, the beast looks like it could seriously hurt a bigger vessel by ramming (this is no joke; it probably could!). These classic landing craft, loved by their crews and prized by the ARG and MEU (SOC) commanders, are still finding new ways to serve.
Like the LCAC, the LCU is a 'double-ended' design, with ramps at both ends allowing vehicles to load by driving through one LCU to get to the next one. They are constructed of heavy steel, welded back in the days where the quality control test was a long swing with a sledgehammer! The LCU may be one of the most bullet-resistant craft in the Navy, which explains why they are frequently used as gunboats and escorts for rubber boats and AAV- 7s. LCUs were built by many contractors, such as Defoe Shipbuilders of Wisconsin, General Ship & Engine Works of Boston, Gunderson Brothers of Oregon, Moss Point Marine of Mississippi, and Southern Shipbuilders of Louisiana. Their construction was simple, requiring no special skills or equipment. Though the original LCUs date back to 1951, the class currently in service, the LCU- 1610s, were built between 1959 and 1985. During all that time, the design was essentially unchanged, except for one experimental unit constructed of aluminum.
The LCU is essentially a floating steel box or barge, with a deckhouse to starboard, fore and aft loading ramps, and some side plating to keep passengers in and water out. Powered by four GM/Detroit Diesel engines (each delivering 300 hp), they are some of the most powerful ships per ton of displacement in the Navy. They are even used as tugs when actual tugboats are not available to push barges and lighters around. When you climb up the bow ramp of a LCU, you are immediately struck by how functional everything is. The chief petty officers who run the LCUs do so in a no-nonsense fashion, without pretensions to polishing the brass or keeping the paint clean. But I defy you to find a line out of place, corrosion forming, or a hatch left undogged. This is the Navy of the old chiefs, where you find little of the high technology or political correctness that permeate the big ships of the 'real' Navy. Aside from a portable GPS receiver in the pilothouse and a small homegrown cable TV/VCR network down in the crew berthing spaces, everything on the LCUs of the 1990s would be familiar to your grandfather, if he was a sailor in the 1940s. The steel deck has tie-down stanchions to keep heavy gear and cargo from shifting in heavy seas; and since the cargo deck is open to the elements, the crew quickly hands you a life preserver. There is a winch-driven anchor system to drag the LCU off of the beach if the tide goes out while it is beached.
The 121-by-25 ft/36.9-by-7.6-m cargo deck takes up most of the LCU's 134.75-ft/ 41.1-m length. The cargo deck can handle up to 1,850 ft/171.9 m of vehicles, troops, and cargo, up to a weight limit of 180 tons! Given that the LCU can deliver this load in almost any seastate, you can see why the Marines like to have LCUs hauling their heavy gear like 70-ton M1A1 Abrams tanks and large palletized-loading-system (PLS) trucks. In a seastate where an LCAC would be unable to haul a single M1A1, an LCU can carry two of the armored monsters, with space and capacity to spare.
The LCUs' long range means that they can be used as utility transports in closed waters (like the Baltic and Adriatic), returning to base to haul fresh food, spare parts, and that vital commodity, mail. LCU crews take working inshore quite seriously, and frequently mount machine guns, grenade launchers, and other weapons. They have even fired 25mm and 120mm cannons of embarked LAVs and M1A1s, which is awesome firepower. The LCU crews see themselves on the cutting edge of the recently reborn art of riverine warfare, and they practice it often in exercises.
As noted earlier, LCUs are warships, with their own berthing, galley, and head facilities. The galley, aft of the pilothouse in the starboard deckhouse, can whip up a full meal. In fact, when they are in the well decks of their mother ships, they require only power, water, and sewage hookups (some also ask for access to the ship's cable TV system) to live independently from the ship's company. They buy their own food from the mother ship's supply system, and even have their own communications call signs for message traffic from higher commands. The living facilities are located belowdecks, along with the engine rooms (there are two, separated to improve survivability), machine shop, and other necessities. You might call the living conditions spartan, but LCU crews like them just fine. In fact, life in an LCU is reminiscent of life aboard a submarine, with many of the same benefits and drawbacks. As with a submarine, the only private space is the captain's cabin, though the commander of an LCU is only a chief petty officer! Don't say 'only' a chief, though, because these men know their stuff! There is a saying in the Navy that if you want someone to think, ask an officer. But if you want it done, ask a chief…nicely!
For all of their age, the LCUs are a pleasure to ride. One of the joys of preparing this book was a late summer ride out to the USS
As you can see, amphibious ships trade about two LCACs for each LCU. Given the LCU's compatibility with older ships like the LHAs and LSD-36s (for which they were designed), it's a shell game to mix and match ships and landing craft to obtain the ideal combination of landing craft for a particular mission. For example, when Captain C.C. Buchanan (Commander of Amphibious Squadron Four, PHIBRON-4) was configuring his force for the 1995/96 cruise of PHIBRON- 4 and its embarked Marine unit, the 26th MEU (SOC), he decided on the following mix. Aboard USS
Landing Craft, Medium (LCM)
The last landing craft we will look at is by far the eldest: the venerable Landing Craft Medium, Mark 8. The LCM-8 is the last direct link with the kind of landing craft you see in old war movies storming the beaches of Normandy or Iwo Jima. The basic design of this long-serving utility craft dates back to a British vessel of the early 1940s. Back then, the requirement was to haul a thirty-ton tank or equivalent load from an offshore transport. Other than increasing the payload capacity to accommodate a modern main battle tank, not much has changed.
The basic LCM-8 is a metal box, with a retractable bow ramp and a pair of 165 hp marine diesels. Most of the LCM-8s are made of high-tensile steel, though some units were welded aluminum to reduce weight for stowage aboard LKA-113-class assault cargo ships. Aft is a small pilothouse. And that is about it. There are armament or berthing facilities for the crew of five (they live aboard their mother ship). The cargo area is open to the elements. The LCM-8 can make about 10 kt/18 kph for a range of about 190 nm/347 km with a sixty ton cargo load or perhaps 125 Marines. An LCM-8 can carry every piece of ground equipment in a MAGTF, except the M1A1 Abrams tank. The LCM-8s roll a fair amount, and can ride decidedly rough in heavy seas. Nevertheless, they are quite seaworthy, despite the pounding that they deliver to their passengers and cargo.
Currently, though the capability does still exist, an ARG carrying an MEU (SOC) would almost never carry LCM-8s. Where you find the LCM-8 is in the three maritime preposition squadrons. There they function as cargo carriers for vehicles and equipment. They act as tugs for barges, and transport personnel between ships. Many allied forces, including Britain's Royal Navy, use the LCM, and will continue to for some time. After a half century of service, however, the LCM's retirement from the U.S. Navy is finally at hand. Within the next ten to fifteen years,
