Saw 5 U-boats , model unknown, in Up Mrechandise headed West from Tucson today. All in gray primer with Nos “UPYXXX”. what’s up?
These were mentioned in the forum a month or two ago. The gray units, when lashed up with any other locomotives, enables them to be controlled remotely. “UPY” reporting marks simply indicate that this is a “locomotive” (it has no engine of its own) assigned to yard service.