What is the term for a train composed solely of locomotives and no cars?

A train composed solely of locomotives and no cars is referred to as a "Light Engine." This term indicates that the train is running light, meaning it is not hauling any freight or passengers at that time. Light engines are typically used for moving locomotives from one location to another, performing maintenance, or positioning locomotives for upcoming service.

Understanding the context of light engines is essential in railway operations, as it helps in planning schedules and ensuring efficient movement of equipment without the need for additional cars. This term is distinct within rail terminology, emphasizing the specific makeup of the train as only consisting of locomotives.

Other terms mentioned, such as "Deadhead Train," generally refer to situations where train crew members are returning to their home station without any cargo or passengers but can include cars. "Freight Train" signifies a train designed to carry cargo, making it the opposite of a light engine. An "Extra Train" typically refers to a service run that is not part of the regular schedule but can still include cars. Thus, "Light Engine" is the most precise term for a train consisting solely of locomotives.