What does the term “train handling” refer to?

The term "train handling" refers to the techniques and skills used by an engineer to control the train. This encompasses a wide range of operational aspects, including accelerating and braking smoothly, maintaining a steady speed, and navigating curves or gradients safely. Effective train handling is crucial for ensuring passenger comfort, cargo safety, and overall operational efficiency. It requires an understanding of the train's dynamics, weight distribution, and the effects of various conditions on performance.

The other options do not capture the essence of train handling: the design of trains pertains more to engineering and structural considerations, the weight of the train cargo is a factor that affects handling but is not the handling itself, and the speed limit of trains is a regulatory parameter that does not address the skill set involved in controlling the train. Thus, recognizing train handling as the application of techniques and skills by an engineer is essential for safe and efficient train operations.