longitudinal members for motor vehicles may generally include a supporting element that is releasably connectable to an energy absorption mechanism . the supporting element may typically include a joining zone that can be used to secure the supporting element to one or more chassis or drive components of the motor vehicle . the supporting element and the energy absorption mechanism may be comprised of fiber - reinforced plastic . more specifically , the supporting element may be comprised of a plurality of length portions having different fiber orientations . for example , a first length portion may have fibers oriented substantially parallel to a horizontal longitudinal plane about which the supporting element is positioned , whereas a second length portion between the first length portion and the energy absorption mechanism may have intersecting fibers oriented oblique to the horizontal longitudinal plane .