Lots of times the CN in Iowa needs a 3rd unit, sometimes called a kicker, to get the tonnage over the grades east of Waterloo. Most days the consist is sent out as a 3-unit set, but sometimes a SD60 laying around will get used. When that happens sometimes it can get to the headend if it's facing right and or there is problems with the other power. As is the case today, the 5421 got to the lead on this loaded ethanol train as a kicker. The unit will set out at Freeport as the 2 NS units are only needed to deliver the train to the NS at Chicago. Seen here passing the former siding at Beth.