[Est.July.4.1776]

By the time I take charge of our coal trains (130 cars, 19,000+ tons) the distributed power locomotives have been removed. All of our coal trains come to us from the BNSF, and the loads come with two head end locomotives, and one distributed power (DP) unit on the tail, which is removed when it hits our Battle Creek terminal. That's where I would take it over. The advantage to utilizing DP units is that it reduces the in train forces exerted on the cars' draw-bars. Our trains are traditionally around .75 ton per foot of length, so a coal train is 3x the weight. Distributed power is also crucial in instances of a steep grade to keep the lead locomotives from stalling out due to the excessive weight, and it helps with a quicker application of the air brakes. Undulating track (rise and fall) can exert a lot of force on a train, with slack rolling in on a downgrade, and stretching out on an incline... it creates a snapping rubber band effect, and a DP locomotive can help reduce those instances. I'm not sure as to an advantage for an intermediate DP unit vs. a tail end unit, but I can say that it would be more advantageous to run a tail end DP unit simply for the reduction in time and effort it would take to remove the locomotive when it is no longer needed (which is the reason they are removed by the time I take them over... our terrain is almost a completely downward grade, so gravity assists in the movement of the train and the extra power isn't needed)

Good question