What about the nasties?

[Greg Beeston]

If the doco on the discovery channel was based in isolated places it was probably about road trains, a tractor with up to three trailers with wheel/axles at each end. Road trains are kept to the outback.
The B double/triple are still a tractor and two/ three trailer combination. the rear of the leading trailer/s has the fifth wheel so trailers attach in the normal methord behind each other, these are common on city freeways and can be seen on main arterial and lesser roads