The procedure applies to heavy vehicles weighing more than 11 800 kg (26 000 lb) and particularly to those vehicles having two or more articulation joints that allow rotation in a horizontal plane. The procedure pertains to the lateral directional response of multi-articulated vehicles in avoidance maneuvers performed at highway speeds without braking. This test procedure is intended to be used for determining the rearward amplification and dynamic offtracking qualities of multi-trailer commercial vehicles (heavy trucks and buses).