"Railfan Rowan" arrived shortly after the derailment and documented what he saw. Super quick work to get this mess cleaned-up in like a day...and a little more.
__________________
If you are in a horror movie, you make bad decisions, its what you do.
Dragging detector announced Emergency stop, so head end NS #310 with 212 cars with distributed power went from notch 8 to dynamics brake notch 8, but had been using trip optionizer and the DPU was a DC drive set and did not react the expected way of killing power. End result of head end braking and mid unit in full power was pushing off the auto racks within the train. Result of PSR. May be time to cash in the stock and take the capital gain hit while there is some left.
The real cause of what was dragging had not been specified.
