Dead weight refers to the combined mass of all trailing cars, their lading, and any unpowered locomotives in a consist. It represents the total physical resistance the active motive power must overcome to start, accelerate, and haul the train. Dispatchers and engineers calculate this to determine the required tractive effort and braking distance for a given route.
Heard on the job
We have too much dead weight for a single unit to pull up the ruling grade without stalling.
Insider tip
A dead-in-tow locomotive counts as dead weight but still requires its air brakes to be cut in and functioning with the rest of the train.