Semi-Truck Loses Trailer on Icy Mountain Road, Sending It Over the Edge Alpine Pass, Switzerland — A routine winter drive through a narrow mountain pass turned into a heart-stopping emergency when a semi-truck lost control of its trailer on an icy curve, sending the massive box sliding off the road and dangling over a steep drop. The dramatic moment was captured as snow and fog reduced visibility and left little margin for error. The video opens with the white tractor creeping along the cliffsid