Može biti:

a) tegljači s više prikolica
http://www.ise.ncsu.edu/kay/mhetax/TransEq/IndusTr/index.htm


b) lokomotive koje vuku brodove kroz Panamski kanal, a moraju imati i još koji vagon s teretom ... radi protuteže težini broda...

Four percent of the world's shipping fleet cannot navigate the Panama Canal. The tow trains are strong enough to pull any ship on earth, but some vessels are too big for the 110 foot wide locks.
http://www.tv.com/towing/episode/327415/summary.html


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Note added at 38 mins (2008-01-09 22:31:17 GMT)
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The 1000 foot-long tow "train" used to tow the EXD-01 aircraft consisted of the tow rope, made of a synthetic fiber normally used in marine applications; a breakable link designed for safety and to break if too much stress was placed on the tow train.
Nylon straps were used on the first three flights in the middle of the tow train for damping to help any spring tendencies in the tow train. The straps were not needed for the last three flights.
http://www.nasa.gov/centers/dryden/news/FactSheets/FS-049-DF...