An overland train is a large vehicle categorized as a tractor-trailer. The vehicle consists of a control truck in front that could tow several cargo cars behind it. This oversized mode of transportation was designed to carry very heavy equipment and can support as much as 150 tons.
During the Cold War, Robert G. LeTourneau was inspired by the idea of building a land vehicle that can pass through any kind of terrain in any kind of condition. He thought of a vehicle with tires so enormous that each one needed its own electric motor in order to be maneuvered. He then developed the overall design of the overland train and commissioned engineer Sam Duncan for the construction.
LeTourneau’s design to have separate motors for each tire provided more traction to the vehicle, especially on roads covered with ice, snow, and potholes. This was very useful since LeTourneau first intended the overland train to heave and carry trees from off-road terrains. After testing the second version of the train in 1954, LeTourneau gave a demonstration to the US Army and suggested that the overland trains can be used for carrying gears and equipment. Having wanted a means of transportation that does not rely on main roads to travel, the Army requested three units be constructed.
An overland train can stretch as long as 565 feet (172.21 m), the longest of which belongs to the Army and spans 600 feet (180 m) in length. It can tow ten freight cars, along with two other cars containing generators. Besides its traveling functionality, the military vehicles also contained small living quarters big enough for six people, complete with a small bathroom and dining space. The trains even had a mini-kitchen built inside and a laundry machine as well. The vehicles were so well-equipped that they gained the nickname “mobile city.”
Another distinct feature of the overland train was its tire placement. The tires were built in almost perfect alignment so that they would only leave two lines of tracks, as if the vehicle was only made with two large tires. The semi-trailer trucks were never put to use, as the Cold War came to an end before the vehicles were even finished.
Today, visitors can see overland trains near the city of Fairbanks in Alaska or in the Yuma Proving Ground Center in Arizona. The overland train still holds the world record as the longest off-road vehicle. In popular culture, Bob Chandler, owner of the monster truck Bigfoot 4, used the trains’ 10-foot (3.048 m) tires, which he bought from a junkyard in Washington.