don't really think it's dangerous. it's just a blast. >> back it up! back it up! >> it's the best thing in the world. >> heidi rides along but hops out to join the watching crowd when they reach the trail's tougher challenges. >> my husband does all of the driving, and i'm more of the spectator, navigator type person. right over the top. you're down. >> this time, in addition to being a spectator/navigator, heidi is also the family photographer. >> this is the first time that we're going to videotape, so we want everybody in the vehicle and mom will videotape it, and it will be a great thing to show. straight down. >> as heidi tapes, mike drives the jeep and the kids up and down a ragged cliff known as tilt-a-wheel. >> hold on! >> when we started the run, i just expected it would be a quick two-minute run and we'd be at the bottom watching the next person go through.