USMC Landing Vehicle, Tracked (3) Bushmaster (LVT-3 or AMTRAC)
Landing Vehicle, Tracked (3) (LVT-3 or AMTRAC).
The LVT(3) was developed by the Borg Warner Corporation, after that company lost the competition to build the LVT(2). The Borg-Warner Model A was the first armored amphibian but its design was rejected in favor of the Food Machinery Corporation (FMC) models which became the LVT(A)1 and LVT(2) in 1942. After their initial failure, Borg-Warner continued development and next produced a prototype of a new LVT with a ramp, the Model B, which was accepted by the US Navy as the LVT(3). One of the main objectives was to provide a loading door so cargo did not have to be lifted over the sides, as was the case for the LVT(1) and LVT(2).
The Model B involved substantial re-engineering. A major innovation was mounting a pair of Cadillac V-8 engines in sponsons, one in each side of the vehicle, rather than in the rear or front as with previous models of LVTs. The Cadillac engines were the same ones used to power the M5 Stuart light tank, proven in combat. This engine arrangement allowed an enlarged cargo space while holding to substantially the same exterior dimensions. The cargo space of the LVT(4), which mounts the engine center-forward just to the rear of the driver, has cargo space dimensions of 150 inches long by 94 wide. The Model B has a cargo compartment 201 inches long by 77 wide, widened further at the two-thirds mark to 97 inches. The Model B thus obtained a substantial increase in overall cargo space, particularly in length, which was critical to transport jeeps with trailers or towed guns.
The LVT(3) had a bottom-hinged door installed in the rear, which dropped down to provide a loading and unloading ramp for troops or vehicles. Armor kits could be installed on the bow, a feature that was used at Okinawa.
6th Marine Division LVT(3) Amtracs with optional bow armor, on the Okinawa beach, 1945.
The Increased cargo capacity of the Model B was justification for a US Navy contract and Borg-Warner at last received the green light to produce the LVT(3), the official designation given to the final version of the Model B. Production of the LVT(3) commenced in April 1944, but it was one year before it was first used in combat at Okinawa. The lag was caused by the requirement to produce sufficient spare parts for the vehicle to replace battle damage as well as the need to train the crews and mechanics in the operation of the new components of the vehicle, particularly the transmission, prior to committing them to action.
Records show that the LVT(3) was very sensitive to the need for maintenance time in between operations or malfunctions would increase. Tracked vehicles as a family have this
fault and even the long line of development leading to the LVT(3), using time-proven parts from the M5 light tank, did not much improve its maintenance requirements.
LVT(3) production totaled 2,964 units in 1944 and 1945 by Ingersoll division of Borg-Warner and Graham-Paige Motor Corp. The LVT(3) was the culmination of the development of the cargo LVT during World War II -- no further modifications were produced by the end of the war. The LVT(3), with post-war modifications including a covered cargo space introduced in 1949, became the standard cargo LVT of the post-War Marine Corps.
A significant modification was made to the LVT(3) during 1949 when its cargo compartment was covered by folding metal doors. The purpose was to block the entry of breaking waves and shield passengers from enemy fire. A small turret mounting a machine gun was also added centered near the bow. The LVT(3)C (the "C" signifying it was covered) bore the brunt of
the fighting in Korea, often functioning more in the role of an armored personnel carrier on land than an amphibious vehicle because the Korean War used the United States Marine Corps as much for its infantry fighting power as for its amphibious capability.
Characteristics of the LVT(3)
24 ft. 6 in.
11 ft. 2 in.
9 ft. 11 in.
Cargo Capacity (no armor)
Two gasoline Cadillac V-8, 220bhp (each)
Cruising Radius (land)
Cruising Radius (water)
Recommended Books about Tracked Landing Vehicles (LVTs or Amtracs)
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