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How Road Trains Work


More Than Just Trucks
Drivers average about 21 hours at a stretch behind the wheel, though the Australian Road Train Association (ARTA) frowns heavily on this. In fact, ARTA recommend just 14 hours per day, at most.
Drivers average about 21 hours at a stretch behind the wheel, though the Australian Road Train Association (ARTA) frowns heavily on this. In fact, ARTA recommend just 14 hours per day, at most.
(Creative Commons/Flickr/Mart Moppel)

Americans in particular are probably skeptical. We've all been on the highway in our little cars, and we've been boxed in between tractor trailers passing each other uphill. We've felt that gust of swirling turbulence coming off a truck as we try to pass. We've all turned our wipers on the "insane fast" setting to try to clear our windshields when the truck ahead of us is throwing spray like its confetti and we just won the World Series.

That ain't nothing compared to road trains.

In the United States, the average truck and trailer combo is about 70 to 80 feet (21.3 to 24.4 meters) long, and it weighs around 40 tons (36.3 metric tons), without any overweight or heavy load permits and whatnot. In Australia, you can attach two of these trailers to a truck, which is known as a B-double. Add a third trailer, and it's called -- you guessed it -- a B-triple. But that still isn't a road train. Those are classified as "long vehicles."

An Australian road train monster has two or three trailers connected by converter dollies, which add a couple of extra axles to the rig. This combo can be up to 164 feet (50 meters) long -- more than twice what we see on American roads. You can even attach a couple of extra trailers to a B-double setup with a converter dolly. This monster can be up to 175 feet long (53.5 meters) -- the maximum allowed on normal public roads. But there's nothing to limit the length of a truck train on private roads, like those owned by the Australian mining companies.

When these guys are loaded to the hilt, they can weigh up to 220 tons (200 metric tons). That's more than five times the weight of the semi blowing you all over the road somewhere in the middle of Iowa.


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