LVT Landing Vehicle, Tracked
The amphibian tractor (amtrack, LVT) was one vehicle which was to play a vital role in the amphibious operations of World War II. The history of the LVT and it's acquisition by the Marine Corps is a story of a "chance of fate", as the vehicle came to the Marines quite by accident. It is the story of an organization looking for a better way to conduct amphibious operations (Marine Corps) and an individual designing a device that could save lives (Donald Roebling). We begin our story with the Marines.
Between 1918 and 1940, the Marine Corps had forecast the nature of the next war in the Pacific and acted to create and organization dedicated to developing expertise in the tactical methods that eventually led to the defeat of Imperial Japan in WW II. The organization was the Fleet Marine Force or "FMF". The creation of the FMF stimulated landing exercises and the development of an amphibious doctrine that highlighted the need for an amphibious vehicle to cross shallow waters and reefs, and permit the attacker to chose their landing points. Up until this point amphibious operations were still very basic and the methods used were too primitive to assault a heavily defended beachhead.
In the early 1920s, Major Earl H. Ellis, stationed at Headquarters, Marine Corps, pioneered the idea of amphibious warfare by lecturing and writing about the need to seize and defend advanced bases in the Pacific. His effort was influenced by the mandates given the Japanese in the Pacific and the end of WW I. Ellis' study examined the requirements necessary to seize advanced bases in the Pacific and was titled "Advanced Base Operations in Micronesia." Approved on July 23, 1921 by then Commandant of the Marine Corps, Major General John A. Lejeune, it became the foundation for Marine Corps amphibious planning. The U.S. Navy incorporated many of Ellis' ideas into their pre-WW II "Plan Orange." This plan called for a thrust through the Central Pacific Islands against Japan that was later developed into the main Allied attack in the Pacific War.
Given the fact that the islands throughout the Pacific were bordered by coral reefs and defended by the enemy on the beaches, the success of an offensive depended on a vehicle with great versatility. What was needed was a suitable vehicle able to carry assault troops and supplies from ship to shore, negotiate the coral reef, and move inland to offload their cargo. By sheer coincidence, a naval officer stumbled across Roeblings "Alligator."
In 1935, a great hurricane swept the Florida Everglades causing substantial flooding to the area. Local inhabitants had, in many cases, drowned, as rescue teams were unable to access the flooded areas. Outraged and concerned, John Roebling, whose father built the Brooklyn Bridge, called upon his son, Donald, to design a vehicle that had amphibious capabilities for rescue missions.
By 1936, Donald Roebling, a wealthy young inventor living in Clearwater, Florida, had already completed his first design for an amphibian and built the first model. It was a light vehicle that featured horizontal paddle-like cleats that gave the vehicle a water speed of 2.3 miles per hour and featured a 92-horsepower Chrysler engine. The "Alligator," as Roebling called his creation, was a track-laying vehicle which derived its propulsion afloat from flanges fixed to the tracks, essentially the principle of early paddle-wheel steamships. The first "Gators" were a disappointment, in that the water speed was slow, and the land speed was 25 mph. Originally intended as a vehicle of mercy, for rescue work in the Everglades, the "Alligator" was destined for fame as an instrument of war.
One year later, Roebling completed work on a lighter four-ton version that had revised diagonal cleats attached to the track, offering an increased water speed of 5.45 miles per hour, and powered by a Ford V-8 engine. His third model of even less weight featured an aluminum hull, a modified track-configuration that now used diagonally curved cleats giving it a water speed of 8.6 miles per hour and a land speed of 18-20 mph.
By 1937, Roebling had attracted considerable attention, and on October 4, 1937, his "Alligator" was exposed to the public eye in Life magazine. The Marine Corps first took notice of the Alligator when Rear Admiral Edward C. Kalbfus, Commander, Battleships, Battle Force, United States Fleet, knew of the Marine Corps' need for a unique amphibian. He had read the article on Roebling in Life and at a dinner, the Admiral brought the article and a picture of the strange vehicle appearing in the magazine, to the attention of Major General Louis A. Little, Commanding General, Fleet Marine Force. Admiral Kalbfus suggested that Roebling's "Alligator" might provide a solution to the Marine Corps' need. General Little was quick to grasp its potentialities and sent the picture and accompanying article to the Commandant. Without hesitation, the article was pushed up the chain of command and ended up on the desk of the Marine Corps Equipment Board.
The Marine Corps had not forgotten the old Christie amphibian, of such bright promise and disappointing performance. Here appeared to be a possible answer. The Board dispatched its secretary, then Major John Kaluf, to Florida to see the vehicle perform and to consult with Mr. Roebling. Kaluf was favorably impressed, and on this basis the Equipment Board reported to the Commmdant that ". . . subject boat has possibilities for use in landing troops and supplies at points not accessible to other types of small boats." In May 1938 the Commandant cited this opinion in recommending to the Navy that " . . steps be taken to procure a pilot model of this type of amphibious boat for further tests under service conditions and during Fleet Landing Exercise No. 5." Both the Navy Board and the Bureau of Construction and Repair endorsed the recommendation unfavorably on the grounds of economy. The boat development program was at last well under way, and it seemed unwise to divert any of the limited appropriations to a purely experimental project, CNO concurred in the recommendation of the Board.
Marine interest in the amphibian tractor persisted, however, and in October 1939, General Moses visited Roebling at his shop in Clearwater, Florida. He inspected the 1atest model tractor, and persuaded Roebling to design a model including desired military characteristics. Through design changes, and by using larger engines, the water speed of the Alligator was increased to 8.6 mph by 1939.
In January 1940, Roebling had completed the new design. The new model which was designated the CROCODILE. The Crocodile had a land speed of 25 mph and a water speed of 9.4 mph. An appropriation was secured from the Bureau of Ships, and work started on the first military model of an amphibian tractor. The Board contracted with Roebling to develop a pilot model with military specifications. The newest model, tested in May 1940, was faster, more durable, unsinkable even when flooded, and agile enough to climb a 55 degree slope. In November 1940 the completed machine was delivered at Quautico where it was demonstrated for the Commandant and a large party of high ranking officers of the Army and Navy. It measured up in every respect save one. Its aluminum construction was not considered rugged enough for hard military use.
When FMC management realized in 1940 that US involvement in World War II was inevitable, they had a decision to make. Because they wouldn't be able to continue making peace-time goods, they would either be forced to close plants, or become involved in producing a war-time product. The decision to manufacture a war-time product led to the company's first attempt at producing amphibious vehicles. FMC entered into a competitive program to develop an amphibious landing vehicle for the Marine Corps. The only prototype for this LVT (Landing Vehicle, Tracked) was a rescue vehicle designed by John Roebling, used on mercy errands in the Florida swamps. FMC engineers redesigned the Roebling Alligator, adapting it for combat.
The new Crocodile tractor was so impressive in every respect, save material, that the Navy contracted with Roebling for 200 of the machines constructed of steel, rather than aluminum. The Marine Corps was impressed enough to give Roebling and Food Machinery Corporation a contract to produce the first Landing Vehicle Tracked or LVT-1. As Roebling did not have the facilities for mass manufacture, he subcontracted the actual constructiou to the Food Machinery Corporation which had a plant in nearby Dunedin. In July 1941 the first vehicle, now designated LVT(1) (Landing Vehicle Tracked), came off the assembly line at the Food Machinery Corporation plant in Lakeland, Florida. To achieve maximum output, the design of LVT(1) was "frozen" shortly after Pearl Harbor and the vehicle put into mass production.
After initial testing and acceptance of the LVT-1, Major William D. Davies, along with four officers and 37 enlisted men were assigned as the first Amphibian Tractor Detachment. Together, they began the organization of training facilities in Dunedin, Florida. They set up their headquarters at the Dunedin Hotel in order to provide barracks and messing facilities. The nucleus of the first amphibious tractor unit was made up of men who trained at Dunedin. The 1st Amphibian Tractor Battalion, Company "A" was formed as a support unit of the 1st Marine Division. Captain William E. Enright commanded the Company and the Executive Officer was Second Lieutenant Victor J. Croizat. The company was detached to New River, North Carolina on December 8, 1941. In February 1942, Companies "B" and "C" were established. About the same time, the 2nd Amphibian Tractor Battalion was being formed around a nucleus of Dunedin trained Marines. Company "A" was formed in December 1941. The company was brought to strength in San Diego and shipped out to Guadalcanal in early 1942 as a reinforcement element of the 2nd Marine Division. The legacy of the LVTs in the Pacific was about to begin.
The LVT1 was a direct copy of the Crocodile, except that it was fabricated from sheet steel instead of aluminum. The LVT-1 was in production from 1941 to 1943. Being heavier, the land speed of the LVT1 was 18 mph and the water speed was 7 mph. A 6 cylinder, 146 hp Hercules engine was used for power. The LVT1 was propelled by two endless chains fitted with cleats, both in the water and on land. The first LVT1's were used as logistic support vehicles only. They were not armored and carried no armament, however, this soon changed. At the Battle of Tarawa, bolted on armor plate was used and the vehicles were equipped with one to four 30 cal. machine guns.
|Speed (land)||12 mph|
|Speed (water)||6 mph|
|Cruising Range (land)||150 miles|
|Cruising Range (water)||60 miles|
|Fuel Capacity||80 gal|
|Gear Configuration||3 fwd - 1 rev|
|Weight (empty)||17,300 lbs|
|Weight (loaded)||21,800 lbs|
|Hull Thickness||3/16 max|
|Track Adjustment||By Idler|
|Armament||Machine Guns, 30 cal.|
|Crew||2 - 3|
|Mfg||Donald Roebling, Clearwater, Fla.|
|Food Machinery Corp., Lakeland, Fla.|
|Food Machinery Corp., Riverside, Ca.|
|Graham-Paige Motor Corp., Detroit, MI.|
|Ingersoll Steel & Disc Division -|
|Borg-Warner Corp., Kalamazoo, MI.|
|St. Louis Car Co., St. Louis, Mo.|
MAJOR CAMPAIGNS THAT THE LVT-1 PARTICIPATED IN:
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