Kinetic element in a winch system?
It’s getting impossible to keep up with even a fraction of the 4x4 driving and recovery videos on YouTube, all of them purporting to offer useful, expert advice. Some actually do. Others are wincingly inept, some downright stupidly dangerous.
There are also plenty that fall somewhere in between.
A recent . . . fad, I’ll call it . . . involves inserting a kinetic element, usually a KERR (Kinetic Energy Recovery Rope) into a winch rig, with the aim of reducing shock loads on the winch and winch line, or in some cases to “pre-load” a winch pull.
I was taught never, ever to include a kinetic, or elastic, element in a winch rig. Even without such an element, a component failure in a winching scenario can result in dangerous recoil of the winch line and anything attached to it. When steel winch cables were the norm, this was especially hazardous, as the spiral twist of the cable tended to violently untwist as the cable recoiled, creating a swath of destruction.
As with most of us, I now use synthetic winch line, which significantly reduces (although it does not eliminate) the dangers of a snapped line or broken recovery point. However, I still have never found the need to use an elastic component, while accepting that in certain circumstances it might be useful.
This is not one of them.
This video, by a fellow called Mad Matt, demonstrates the insertion of a KERR in a winch system to prevent the vehicle shown from violently bouncing at the end of the winch line as it winches itself up a steep rock face while the driver attempts to apply power. As demonstrated, one easily sees how the elastic nature of the KERR reduces the shock loading on the winch line.
The operative words here are “as demonstrated,” because the shock that is actually demonstrated is shockingly bad driving skills. Perhaps that was Matt’s aim, but if so he failed to point it out, leading many who watch this video to assume that the correct way to assist one’s winch while being pulled uphill is to apply great gobs of wheel-spinning torque so the vehicle bounces wildly against the winch line.
The entire sequence is completely unnecessary. There is absolutely no reason for the driver to apply any power in this situation; the winch should be doing all the work until the vehicle is back on terrain with adequate traction. If the winch is not powerful enough to do so with a single-line pull, a double-line pull would accomplish it, drawing the vehicle slowly and safely up the slope, eliminating the bouncing and the hazard of the kinetic rope, along with the two extra shackles needed to include it.
In short, whenever possible it is a good idea not to turn your winch rig into a giant slingshot.
