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It was a wet Sunday in March. From time to time snow squalls would blow through coating the vehicles but melting as soon as it toughed the ground. Occasionally the sun would peek out. Normally hard-baked clay trails with traction like slick rock had become slick and greasy. I had been picking the more sandy trails for my class of new enthusiasts. It was about 3:45 PM and I had just shifted to 2WD in preparation to lead the beginning class out of the Park when the last vehicle in our group was intercepted by a vehicle looking for help. A Toyota land cruiser had flipped over. Fortunately no one was injured.
On inspection, what appears to have happened is the individual was descending a steep hill. It was very muddy, kind of slick and had one significant left turn. He probably was trying to slow the vehicle down and locked the wheels up, which created understeer. As a result he did not make the left hand turn the road required. The right-side, front-wheel went up on the bank and flipped the vehicle completely over. The vehicle came to rest just inches from the left hand edge. Another few inches would have resulted in tumbling several hundred feet down through the brush. Everyone was wearing their seat belt - except the dog. The dog at one minute was standing on the seat and the next he was walking on the roof. They were able to roll down the windows and climb out.
The recovery required a two-step process
There wasn’t room to actually flip it over where it landed. At best we could have put it on its side before the wheels would touch the opposite bank and prevent it from landing back onto it wheels. We needed to pull the vehicle down hill 10-15 feet. Given its precarious position, right on the edge of the bank, the concern was that it would act like a pendulum on the end of the winch line and swing it off the bank. Therefore, we attached a strap from a tree on the bank to the rear corner of the frame. A Hi-Lift jack was used to take the slack out of the line. When the winch pulled the vehicle forward, the rear of the vehicle was pulled into the center of the road.
Once the vehicle had been pulled down hill to a wider spot in the road, we were able to re-rig and flip it over on to its wheels. In the re-rigging, the closest substantial tree was over 50 feet up the side of the bank which necessitating using a synthetic extension rope. We attached it to the tree with a strap and clevis, dropping its full 50 feet down to another clevis with a pulley. Then the winch was spooled-out from the vehicle through the pulley block to a chain that was attached to the center of the far frame about where the cross member is attached. If we had pulled straight across the frame there is a chance that the vehicle would have only slide sideways on the roof. Therefore a “stiff leg” was placed against the near frame rail standing upright with the winch cable passing over the top of it. The board used was a roughly two feet long 2x8. The stiff leg had the effect of forcing the winch line to create downward force on the side opposite the attachment point and upward force at the attachment point which started the vehicle rolling over. At some point as the vehicle rolled to its right, the winch line became straight with the pulley block and the stiff leg fell out. The winch continued pulling until gravity took over and the vehicle fell back on its wheels. The winch line prevented the vehicle from rolling down the hill. After cleaning up the spilled fluids, we used a tow strap to pull the vehicle out to the pavement.
Analysis of the chain of events
A long day of wheeling with everything working well, can lead to over confidence. He had been doing relatively well all day. The vehicle had good mud terrain tires and the vehicle was performing very well in the slippery mud. He may have become over confident and came into the rather steep down hill faster then he should have. When it started to slide, he panicked and braked causing it to go into a skid in an understeer situation. What he needed to do was stay off the brakes and power up a bit to give him control and turn into the slide.
By powering up a bit and he would have had steerage and he would have been able to make the left. However, given the conditions probably the last thing he wanted to do was go faster down a steep, slippery hill. One thing they did right was wearing their seat belts. This was a good solid vehicle. It had good tires. Every one was calm, and sober, so drugs and alcohol played no role in it.
Conclusions
You need to learn how to react to off-road situations. Your natural instincts are quite often wrong. In this case, it meant staying off the brakes and adding a slight bit of power.
A lot of the bad things happen at the end of the day when you are tired or over-confident. Being tired or over confident results in a lack of focus needed off-road. Head home or back to camp early when wheeling in intense conditions.
Before winching, consider the results of the placement of the disabled vehicle. Are you likely to create a more difficult situation? If it slides off the bank, will it pull your vehicle with it? Can you control the vehicles movement when it is back on its wheels? Make sure the emergency brake is set and the vehicle is in park or in gear so it will not roll once back on its wheels.
Pictures of the Roll Over
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