Are tractor-trailer accidents always head-on collisions?

No. Tractor-trailer accidents are not always head-on collisions. The types of accidents that big rigs may be involved in include rear-end collisions, broadside or T-bone wrecks, head-on collisions, lane change accidents, rollover wrecks, jackknife accidents, loss of control of the rig, hit and run accidents and center-lane crossovers.