Le Tourneau Logistical Car TC-497 Overland Train Mark II

Six years later, (1961) LeTourneau made one final stab at building the ultimate land train. Designed to traverse arctic conditions as well as sand and desert, the six-wheeled TC-497 Overland Train MkII used four solar gas-turbine engines (at 1,170hp each, thats 4,680hp total) to spin generators that delivered juice to 54 total motors one for each of its wheels. Of its 12 trailers, two were dedicated just to carrying the turbines and generators. The Overland Train stretched 572 feet long, easily making it the worlds longest vehicle. Funny enough, it could only carry 150 tons of freight as much as the Sno-Freighter though it carried such developments as steerable trailer wheels that allowed the entire train more maneuverability.
The Army started testing the Overland Train in 1962, the same year Sikorsky introduced its large freight helicopters that rendered the land trains obsolete. The fates of the Tournatrain and the Sno-Buggy are uncertain. The Sno-Freighter, however, sits abandoned with at least three of its trailers outside of Fairbanks, Alaska, as does the LCC-1, with just one of its trailers. The Overland Train, minus all of its trailers, sits today at the Yuma Proving Ground Heritage Center in Arizona. BigLorryBlog also has more photos of the Overland Train in another recent post, and LIFE shot a series of photos of the Overland Train testing at Yuma.
Steering such a train proved to be a serious problem. ( began with the first train - VC-12 Tournatrain .
All that remains of the Mark II is the control cab which remains at Yuma.
LCC-1 was so successful that in 1958 the Army contracted for a larger version, TC-497 Overland Train Mark II. Generally similar to the LeTourneau LCC-1 in concept, the Mark II included a number of features to allow the train to grow to any length.
One change was the removal of the Cummins engines and their replacement with gas turbine engines of higher power and lower weight. Whereas the LCC-1 had a single 600-hp engine, the Overland Train had four 1,170-hp Solar 10MC engines, one in the "control car" and three others spread through the train. New power trailers could be added at any point along the train. To further reduce weight, most of the vehicle was built from welded aluminum.
Steering such a train proved to be a serious problem. ( began with the first train - VC-12 Tournatrain . If the train rounded a corner, the trailers would normally want to even the angles between themselves, forming into a long arc. If there was an obstacle that the driver had avoided, the trailers might eventually hit it as they rounded a corner. To solve this problem, the new trailers were all equipped with steerable wheels. Steering commands were sent from the control cab to each set of wheels in turn, so they started turning at the same point where the driver had. This allowed the train to make sharp right-angle turns, for instance.
The Mark II had a much larger six-wheeled cab that was over 30 feet (9.1 m) tall and was no longer articulated due to the ability for all the wheels to be steered. The turbine engine was much smaller than the diesel it replaced, allowing the interior to support a crew of six with sleeping quarters, toilets and a galley. It was even equipped with a radar. An additional two power cars and ten cargo cars were built for testing. In total the train now stretched over 570 feet (170 m). On flat ground it could carry 150 tons of cargo at about 20 mph. Range at full load was normally 350 to 400 miles (560 to 640 km), but additional fuel trailers could be added to extend it.
Final specifications were completed in 1960, and construction took most of 1961. After preliminary testing, it was handed to the Army in February 1962, and shipped to the Yuma Proving Ground in Yuma, Arizona. In testing under the "Project OTTER", for "Overland Train Terrain Evaluation Research", the vehicle performed well. But in the end the Army gave up on the idea as newer heavy-lift helicopters like the S-64 Skycrane made the train concept outdated.
The vehicle remained unused for a time, and was then put up for sale for $1.4 million in 1969. All that remains of the Mark II is the control cab which remains at Yuma, the rest was sold off to a local scrap dealer. The Mark II retains the record for the longest offroad vehicle in the world.
(Land Locomotion Mechanical Vehicle Mobility LL-MVM) Home