LVT Class, Allied Landing Craft

Naval History and Heritage Command #Nh 97749

LVT(1)

Specifications:

Landing Vehicle, Tracked, or LVTs, were also known as amtracks, Alligators, or (in their fire support variants) as Water Buffaloes. They were amphibious tracked vehicles capable of crawling out of the water and onto the beach and beyond. Later versions were thinly armored, and some were equipped with a light tank turret to provide fire support, making them equivalent to light amphibious tanks.

The LVT had its origins in the Florida hurricane of September 1935. Donald Roebling was encouraged by his father to develop an amphibious vehicle, the Alligator, as a rescue vehicle for hurricane victims and for downed aviators in the Florida Everglades. The Alligator used aluminum in the hull, a novel practice at the time, to minimize weight. It also had unusual track gear to reduce drag and paddle cleats on the tracks for better water propulsion. A Life article in October 1937 brought the Alligator to the attention of Marine brass, but both the Navy and Roebling resisted Marine procurement, the Navy because it felt it had its hands full with conventional landing craft, and Roebling because he wished his invention to be used only for peaceful purposes. Roebling was persuaded otherwise by General E.P. Moses after war broke out in Europe, and Roebling completed a militarized prototype by May 1940. The Bureau of Ships requested a second prototype with a more powerful engine, and the Marines finally got their opportunity to test the design in November 1940. Impressed by the second prototype, the Bureau of Ships placed a contract for production of 100 units of a model using all-steel construction, for a more rugged and easily produced design, and the first of these LVT(1)s was delivered in July 1941. Another 200 units were ordered even before the first production units were delivered.

LVTs proved remarkably seaworthy and, with their low silhouette, were difficult to hit while still in the water. They could turn in the water in their own length while running at full speed. Their thin hull (constructed largely of 12 gauge sheet steel, 0.1046" or 2.7mm thick) was too thin to provide much protection from fire, but some were retrofitted with 9mm of cab armor in time for the Tarawa invasion. They could climb an incredible 60 percent grade. They did not need to stop at the waterline, where the defenders often had their guns zeroed in, to disembark troops and cargo. Their greatest weakness was their very slow speed afloat, due to the inefficiency of the tracks in water. They were also relatively complex machines, with an average mechanical life estimated at just 200 hours.

A battalion of LVTs was ready for 1 Marine Division by 16 February 1942. However, the LVTs did not see their first operational use until Guadalcanal, where they were used exclusively for landing supplies. About 128 LVTs were available for the landings. Turner was unimpressed with the craft, but Holland M. Smith and the Marines praised its versatility, believed in its potential, and called for further improvements. Smith later declared that (Bailey 1976):

The development of the amphibian tractor, or LVT, which began In the middle 1930's provided the solution and was one of the most important modern technical contributions to ship to shore operations. Without these landing vehicles our amphibious offensive in the Pacific would have been impossible.

As early as January 1940, Roebling had prepared preliminary sketches of an LVT with a gun turret to provide fire support to the landing waves. However, the concept languished until June 1941, when the Commandant of the Corps recommended development of an LVT armed with a 37mm gun and three machine guns and armored against 0.50 (12.7mm) machine gun fire. Development was slow and ultimately involved a complete redesign of the LVT.

Engineers from Borg-Warner carefully evaluated the LVT(1) and concluded that its track mechanism was unsuitable, due to a tendency for sand to work its way into the roller bearings and jam them. There was also criticism of the propulsive efficiency. Borg-Warner and the manufacturer of the original LVT(1), Food Machinery Corporation, began work on competing new designs. FMC was assisted by faculty from Caltech and the University of California and developed the designs that became the LVT(2) and the LVT(A)1. Borg-Warner took a more cautious approach, and their Model A never advanced beyond the prototype stage. However, their use of an M3 tank turret was adopted for the LVT(A)1. Interest in the LVT was great enough that the Secretary of the Navy formed the Continued Board for the Development of the Landing Vehicle Tracked on 30 October 1943.

LVTs were first used to bring troops ashore at Tarawa, where they were the only landing craft able to cross the shallow reef and deliver their troops to the beach. Unfortunately, there were only 50 LVT(1) and 50 LVT(2) available for the assault, which not nearly enough for the entire landing force, and most of the troops had to disembark from less capable landing craft and wade across the reef in the face of withering fire. The LVTs were brought in on LSTs, which could get close to shore and thus shorten the run to the beach for the LVTs, whose mechanical reliability was never as great as that of less complex landing craft. (Part of the difficulty was the peculiar steering mechanism, which tended to freeze if steady pressure was applied to the steering lever instead of a sequence of pulls and releases.) Troops were transferred to the LVTs from their troop transports usings LCVPs, a time-consuming procedure, requiring nearly two hours to complete. Most of the LVTs used at Tarawa were field modified with cab armor and additional machine guns, and the added weight reduced speed afloat significantly. As a result, the LVTs took longer to reach the beaches than anticipated, and the troops were unsupported by naval gunfire or ground air support for the last ten minutes of their approach. Eight LVTs were destroyed before reaching their beaches, and another 15 were sunk when they attempted to back off the beach to pick up more troops. The latter had hulls perforated by machine gun fire, and the bilge pumps proved inadequate to keep up. (In subsequent assaults, the LVTs would carry wooden plugs for their crews to hammer into bullet holes.) The remaining LVTs were switched to bringing in cargo, since conventional landing craft were unable to carry critical supplies across the reef.

Notwithstanding these difficulties, the casualties among the troops brought in by LVT were so much less than among troops brought in by conventional landing craft that Holland M. Smith stated (Bailey 1976): 

After Tarawa, I made up my mind that all future landings would be spearheaded by amphibious vehicle, either the open-decked amtrac, of which a new improved model was already being made available, or amphibian tanks, carrying heavier guns, which were in production.

Holland recommended that each Marine division be equipped with two battalions of LVTs and a battalion of LVT(A)s. Production of LVTs received a high priority, reaching 500 per month in the early part of 1944. Such numbers were needed because of the short lifetime of the vehicles: Only 35 LVTs were still operational after three days' heavy fighting at Tarawa. Later invasions were thus more amply supplied with LVTs, which were deemed essential whenever the shore was protected by a fringing reef. For example, the Roi-Namur invasion, which took place just two months after Tarawa, was supported by 350 LVTs and LVT(a)s. LCVPs continued to be used where there was a sandy beach without a shallow reef.

Many lessons were learned from the Tarawa invasion. The unarmored LVT models were eventually supplied with portable armor that could be attached for the initial assault then removed to increase cargo capacity for subsequent supply operations. The procedure of loading LVTs from LCVPs in the wave assembly area was so problematic that it was only repeated once, during the preliminary landings at Kwajalein. During the main Kwajalein landings and in all subsequent operations, the assault troops were brought to the LSTs to be embarked on the LVTs.

The craft proved highly versatile. The LVT(A)1 first saw operational use during the Saipan campaign. From the Peleliu campaign on, a number of LVTs were fitted with a flamethrower for use against fortifications. The vulnerable LVT was usually flanked by a pair of gun tanks for protection. As greater numbers of LVTs became available, a number were converted to armored ambulances carrying a doctor and three corpsman. LVTs were also employed as guide boats for tanks unloading onto submerged reefs, since if the LVT ran into a shell hole it would float and the tanks would not.

They were relatively expensive landing craft at $35,000 apiece.

Total Production

The following table gives total production.  Almost all of this went to the Pacific, though a small number were given to the British as Lend-Lease and were used during the clearing of the approaches to Antwerp.

Production by type

Photo Gallery

U.S. Marine Corps	Library of Congress	NARA	NARA	NARA	NARA
U.S. Marine Corps	U.S. Marine Corps	U.S. Marine Corps	U.S. Army	NHHC	U.S. Marine Corps

References

Bailey (1976; accessed 2013-11-26)

Cowdrey (1994)

Friedman (2002)
Gilbert (2001)

HyperWar (accessed 2007-12-28)

Icks (2012-8-6; accessed 2014-1-9)
Leighton and Coakley (1955)

Morison (1951, 1953, 1959)

The Pacific War Online Encyclopedia © 2007-2009, 2011-2014 by Kent G. Budge.  Index

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