How does the rotation of the TTMA-100 affect its safety performance?
The TTMA-100’s ability to rotate represents a major improvement in TMA safety technology. While competing trailer attenuators utilize rotational restraints to prevent the attenuator from rotating, the TTMA-100 allows the trailer to rotate in order to keep the system aligned with the impacting vehicle to maximize energy dissipation. It is this innovative approach to energy management that has allowed the TTMA-100 to become the only TMA system to successfully pass NCHRP Report 350 optional offset and angled tests when attached to a support truck blocked against forward motion. The primary concern about allowing a trailer to rotate is that the impacting vehicle would push the trailer out of its path and directly strike the rear of the support truck. However, as shown in the Figure 1, an impacting vehicle must slide along the trailer’s impact face in order to disengage from the trailer.
