ROAD SWITCHER

A 'road switcher' is a type of railroad locomotive used for delivering or picking up cars outside of a railroad yard. Since the road switcher must work some distance away from a yard, it needs to be able to operate at road speeds, it must also have high-visibility while it is switching, and it must have the ability to run in both directions. For these reasons, road switchers are generally hood units. The set-back cab of a hood unit provides more safety in the event of a collision at speed than most switcher designs, and the rear visibility is much better than that of a cab unit. Due to their ability to both run at road speeds and switch cars, road switchers are often used for yard switching and freight duties.
The ALCO RS-1 was the first successful example of the type, and virtually all modern hood units are laid out in the same fashion.