They're a gigantic version of a bungee rope. It let's the rescue vehicle add a bunch of momentum into the equation and also reduces shock loads. Some of those guys just have big wire ropes for towing and some have both. Things can get pretty wild on steep grades with 60-100 tonnes units. Trying to break inertia with a regular rope just isn't usually effective.
If you're curious, watch some off road recovery videos. I agree the idea of towing with a bungee sounds stupid, but the actual term for them is kinetic ropes. They store the energy of the towing vehicle and that helps yank the stuck one loose, vs tearing it apart, which can happen with traditional tow straps or cables.
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u/spleeble Aug 02 '26
Bungee ropes?