Google/Youtube for "Alpine Slide". It's more like a summer bobsled, not like that new monorail thing. At a glance I see one at Park City. There is one out here in New Hampshire at Attitash ski area. I've done it a few times, it's great fun. You sit on this little cart that has plastic sliders on the bottom. You control it with a throttle/brake lever between your legs. Push forward and wheels go down lifting half the sliders off the track. Pull back and rubber brakes go down. Let the lever rest in "neutral" and neither the wheels nor brakes contact the track, just the sliders.
These guys are going pretty slow at first, but you get the idea.
(There is no crash landing or wipeout, not sure what they're talking about. I don't know these people. But yes, it is very possible to leave the track if you don't use the brakes.)
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