Driving an 18-wheeler or tractor-trailer safely requires specialized training and considerable experience. Semi-trucks and their tractors, often fifty to sixty feet long, have large blind spots, and are much more difficult to maneuver through city streets than smaller vehicles. When a large truck makes a tight right-hand turn, the driver swings the front of the truck to the left and drives part way across the intersection before turning the cab’s wheels right. While this maneuver allows the truck to clear obstacles on the right hand curbside, it also places traffic at the truck’s sides and in oncoming lanes at risk of an underride or head-on collision. As the tight right turn is being executed traffic stopped at the cross-street into which the truck is turning is at risk of an overrun collision...more