Military Review

LeTourneau TC-497: Doomsday centipede


LeTourneau TC-497 Mark II on trials in Yuma. Source:

Age of giants

In the 50s and 70s of the last century, the engineering thought of car manufacturers was distinguished by a genuine creative flight. The cold war raged in the world, and this provided considerable investment in defense development.

The technical revolution that swept the armies of the world after World War II required non-trivial engineering solutions in the field of transport. The second engine of progress was low prices for fossil hydrocarbons. Together with the lack of environmental standards, extremely voracious multi-ton monsters went into production.

In the Soviet Union, the Special Design Bureau of the Moscow ZIL and the Belarusian MAZ were responsible for all the most progressive in the military automotive industry. The first company was headed by the legendary Vitaly Grachev, and the Minsk SKB was headed by no less eminent Boris Shaposhnik. Naturally, one should not forget about the unique developments of the capital NAMI, a considerable part of which was occupied by defense vehicles.

Tank carrier LeTourneau T4. Source:

Overseas also did not sit idly by. And in many ways they set the tone for the world military automotive industry. The status of the No. 1 automobile power required conformity.

In all the variety of military equipment, a special place is occupied by the machine of the now little-known company LeTourneau.

The company was founded in 1919 by Robert Gilmour LeTourneau and has focused on gigantic dimensions from the very beginning. The office became famous for the supplies to the American army of the LeTourneau T4 tank carriers with an articulated frame. The first cars appeared in the military in 1944 and they were mainly engaged in transportation tanks M4.

400 hp Sno-Buggy TC264. Source:

In 1953, LeTourneau was renamed RG LeTourneau-Westinghouse due to the merger with WABCO. In 1954, the renewed firm receives an order for a snowmobile for a US military base in Antarctica.

As a result, a unique 21-ton 400-horsepower Sno-Buggy TC264 with an electric transmission is sent to the army. The two-axle vehicle was equipped with eight dual low-pressure wheels. The giant hubs housed in-house motor-wheels.

"Snow Train" Sno-Train LCC1 for the needs of the US Army. Source:

Based on the snow buggy, in 1955 LeTourneau built the Sno-Train LCC1 snow train with three trailers and a 45 tonne capacity. The only vehicle successfully operated at American military installations in Greenland until 1962. The scheme of a land train for ice and sandy deserts was as follows: the "locomotive" housed a 600-horsepower Cummins diesel generator, feeding the motor-wheel on active trailers via power cables. Later, this logic was scaled to other projects of the firm.

Transphibian Tactical Crusher in action. Source:

Before moving on to the main character stories - to the monstrous LeTourneau TC-497, it is worth mentioning the "tactical floating crusher" Transphibian Tactical Crusher.

The main task of this 95-ton armored combine was to make passages for American infantry in the Vietnamese jungle. The monster rested on the ground with three hollow steel drums, providing buoyancy to the structure.

3,7-meter drums with built-in electric motors broke and chopped Vietnamese wood, freeing a many-meter clearing in the forest for soldiers and equipment. It is known about two built machines, differing in the design of the drum-crushers. This development alone would have been enough for LeTourneau to enter the global automotive exotic hall of fame.

But the really crazy project was the 450-ton LeTourneau TC-497 road train, developed as part of the OTTER (Overland Train Terrain Evaluation Research) project.

Project OTTER

By the late 50s, the American army needed a vehicle capable of moving several hundred tons of cargo in a nuclear apocalypse. It was assumed that the Soviet Union with a series of several strikes paralyzes the railway communication in strategic directions.

The solution seemed to be found in the construction of a giant land train on low-pressure tires. Moving along a pre-planned route, such monsters had to provide post-nuclear logistics for some time. The project was named OTTER (Overland Train Terrain Evaluation Research) and the basic requirements for the car were formulated by 1958.

LeTourneau TC-497: Doomsday centipede

LeTourneau TC-497 Mark II. Source:

It should be noted that the idea, which now seems absurd, was not new. By that time, LeTourneau had already developed and tested a similar "caterpillar", only as a timber carrier. The VC-12 Tournatrain was built in 1953 according to a proven scheme with two Cummins V-12 diesel generators (1000 hp in total) and 32 motor-wheels.

The developers even managed to solve the main problem of handling such a long and flexible structure when cornering. A sophisticated electronic system at a strictly defined time turned the wheels of the trailers, allowing the train to perform a snake and ride in a circle.

Despite this, the car did not receive distribution, as it was extremely clumsy in urban conditions.

Experimental timber carrier VC-12 Tournatrain. Source:

In military performance, the land train was named LeTourneau TC-497 Mark II and was much larger than its forest ancestor. The maximum length was about 200 meters, and the curb weight was more than 450 tons, of which 150 were payload.

It is still the longest overland road train in the world. And very big - the height of the head car with the cockpit was more than 9 meters! The record cost was also $ 3,7 million, which was astronomical for a vehicle for the late 50s.

Diesel engines were hardly suitable for such a colossus - the installation of oversized marine engines was required, and this was unacceptable for land equipment. Gas turbine Solar 10MC with a capacity of 1170 liters turned out to be quite compact. from. each, which in the amount of four pieces were installed in the head "locomotive" and three intermediate trailers. As usual, engines with a total capacity of under 5 thousand liters. from. generated electricity transmitted to 54 wheel motors.

For each trailer, the front pair of wheels was steerable, which allowed the centipede, through a sophisticated electronic system, to avoid obstacles, move in an arc, a snake and in a circle. By the way, the diameter of each wheel was 3,5 meters.

The choice of low-pressure tires was not accidental - this was the only way to achieve the necessary ground pressure for a car weighing in total under 450 tons.

All this suggests that the main elements of the TC-497 were sand and snow. The crew consisted of six people, for whom all the amenities were provided - a galley, toilet, laundry and rest rooms. Engineers even managed to install a locator on the roof of the head machine. The very design of the train was modular and, theoretically, allowed the monster to stretch for several kilometers.

LeTourneau TC-497 Mark II on trials in Yuma. Source:

The first and, as it turned out, the only LeTourneau TC-497 went for trials in red livery in February 1962 at the Yuma proving ground in Arizona. The whole thing, of course, was in an atmosphere of strict secrecy. With a full refueling, the road train was able to travel up to 650 km in a desert climate. It was easy to increase the range of the vehicle - just a few trailers with fuel were enough.

The maximum speed during the tests was recorded within 35 km / h. The land train for the Doomsday passed the test of the desert with dignity. And at LeTourneau they were waiting for the decision to enter service.

But Sikorsky ruined everything with its newest CH-54 Tarhe transport helicopter. Simple calculations showed a clear benefit from operating flying trucks over land trains.

Ten to twelve CH-54 Tarhe were capable of carrying cargo that required one giant LeTourneau TC-497. It was also much faster, and it didn’t need to be so carefully plotted.

Monument at the Yuma test center. Source:

Six years after testing its record-breaking model, the LeTourneau military unit closed. And the six-wheeled head section of the mega-train now serves as a monument at the Yuma test site.

And no one really knows where the unique trailers have gone.
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  1. Aag
    Aag 1 March 2021 18: 33
    The author has pleased me once again! Thanks.
    1. sleeve
      sleeve 1 March 2021 19: 07
      And rightly so. Very informative...
    2. Proxima
      Proxima 1 March 2021 20: 32
      Very original article! I never thought that the Americans would get so seriously confused with the road trains of the apocalypse! And the ice rink for laying the Vietnamese jungle is actually something! fellow Interesting and informative! good hi
  2. Alien From
    Alien From 1 March 2021 18: 58
    Amazing technical solutions! Respect to the author, very interesting!)
  3. Cowbra
    Cowbra 1 March 2021 19: 14
    Collosal))) This is where the mad maxes creep out ...
    1. Catfish
      Catfish 2 March 2021 00: 29
      Wherever there, Max never dreamed of this! wink

      My sincere gratitude to the author for an interesting article, for me this is absolutely new information. good
  4. honda
    honda 1 March 2021 19: 40
    Thanks. Very interesting
  5. Avior
    Avior 1 March 2021 20: 54
    Interesting and informative article
    Respect for the author
  6. Blacksmith 55
    Blacksmith 55 1 March 2021 21: 57
    I have never heard of such "cars", thanks, although I was always interested in technology, especially on wheels.
  7. Ilya Nikitich
    Ilya Nikitich 1 March 2021 22: 21
    I heard that in Australia a similar miracle carries ore.
  8. Stepan S
    Stepan S 2 March 2021 10: 20
    Nice, interesting article. There is not even a reason to quarrel on the forum in it))
    1. volodimer
      volodimer 2 March 2021 15: 11
      And he (the reason) is definitely needed laughing ?
      Really interesting article. Of course, the Transphibian Tactical Crusher is weak against our all-terrain vehicles, but as a technical solution, it is at least interesting and deserves attention.
      And the centipede is clearly the legacy of Admiral Byrd's Snow Cruiser wheeled all-terrain vehicle for Antarctica.

      Powerful motor and huge wheels. Our designers preferred the caterpillar track.
  9. Mustachioed Georgian
    Mustachioed Georgian 2 March 2021 15: 39
    The company is widely known in narrow circles. ALROSA uses such
  10. businessv
    businessv 3 March 2021 12: 57
    And the six-wheeled head section of the mega-train now serves as a monument at the Yuma test site.
    Very interesting article! I did not even imagine that such transport existed. Many thanks to the author! good
  11. Boratsagdiev
    Boratsagdiev 3 March 2021 15: 28
    It is still the longest overland road train in the world.

    In Australia, the world record for a road train is 1474 meters.
    And road trains weighing under 200 tons are in the order of things.
    1. DiKoff
      DiKoff April 17 2021 11: 42
      only it is necessary to write that there were 112 trailers with a total mass of 1300 tons and he drove only 140 meters with a MAK tractor and died ... in this advertising campaign of trucks, but the guys at Kenworth with trailers 1235 meters long, 87 trailers and a total weight of 1079 tons traveled 8 km. And everything was on a perfectly flat highway, so the comment is not a topic. Since it is also 200 tonnes, this is only a highway or the ground is perfectly flat. And LeTorno rode on rough terrain and without distance restrictions, fill up the fuel and service.
  12. DiKoff
    DiKoff April 17 2021 11: 29
    LeTorno gained tremendous experience, on the basis of which he built the world's largest front loaders, and now it is a division of the US Caterpillar, like Oshkosh.