CRASH OCCURED AS VEH 1 WAS TRAVELLING NORTHBOUND ON I-29. VEH 1 TRAVELLED OFF THE WEST SIDE OF THE ROADWAY ONTO THE GRASS MEDIAN. THE UNDERCARRIAGE OF VEH 1 STRUCK AN EMERGENCY CROSSOVER AND BECAME AIRBORN.THE FRONT BUMPER OF VEH 1 STRUCK THE GROUND AND VEH 1 CONTINUED NORTHBOUND THROUGH THE GRASS MEDIAN AND BEGAN OVERTURNING. THE DRIVER OF VEH 1 WAS EJECTED FROM THE VEHICLE. VEH 1 CAME TO REST ON ITS ROOF, FACING WEST, PARTIALLY ON THE EAST SHOULDER OF SOUTHBOUND I-29 AND PARTIALLY IN THE GRASS MEDIAN. ASSISTED BY TPR B.A.JONES (649), ATCHISON COUNTY SHERIFFS DEPARTMENT, AND THE ROCKPORT FIRE DEPARTMENT.