![Two Union Pacific diesels lead a unit train of rotary-dump coal gondolas](https://www.trains.com/wp-content/uploads/2021/06/MRR_QA_unit_coal_train_with_rotary_ends_0707.jpg)
Q: When I run a unit coal train of Bethgon Coalporter gondolas, should the colored (rotary) ends face toward the front or the rear of the train? Which is most prototypical? – Nathan Penn, Monmouth, Ill.
A: If possible, a double-rotary-ended car should be the first car in the train, since the coupler on the locomotive doesn’t rotate. After that, it doesn’t matter which direction the single-rotary-ended cars face, as long as they all face the same direction. If any cars facing the other way were mixed in, you’d end up at some point with two non-rotating couplers joined together, and that’s trouble. If no double-rotary-ended cars are available to head the train, the cars should all be oriented with their rotary ends toward the front, as seen in Cody Grivno’s photo above. Distributed power in the middle or at the back of the train must also be isolated with double-rotary cars, or else cut out of the train when going through the rotary dumper.
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