>> 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 are going to videotape, so we want everybody to be 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 would be at the bottom watching the next person go through. >> but only seconds later, heidi