The Goodyear Rolligon tire development program has partially explored a field of extremely low pressure tires and the application of these tires to vehicles as a means of extending vehicular mobility.The tire characteristics explored have included: Low ground bearing pressures. Flexible tire surface and side wall. Deflection at operating loads and pressures. Low skin stresses in tire surface.The program has also included the exploration of vehicle design concepts such as: Utilization of walking beam. Integral central inflation system. Axle and peripheral drive and loading. All wheel drive.Field testing indicates that increased tired vehicle mobility has been achieved.