Was just watching a very long 12,000 ft. drag freight coming off the west shore Rochester bypass in Fairport. The train had to stop evidently could not get the mainline switch at Wayneport and the engineer did halt the train immediately after clearing the Main St crossing and raising the gates, question is with no crew members at the rear how did he know when and where to stop.
The crew is given a train consist which includes train length. The engineer has a distance readout which he (or she) can zero, like resetting your trip odometer. So if there is a chance he'll need to stop, he can zero that at the crossing, and when the readout shows he has gone X feet the rear end is just about where the head end was when it started counting.
The way I described above applies to some of the older systems. I am not sure whether the latest telemetry can show distance between the engine and FRED just from the communication, or whether they must rely on info provided to them when the trip starts.
