Union Pacific Railroad Company Rolling Stock Photographic Roster
Reporting Marks: UPRQ
AAR Class:
NF: A device mounted on the trailing coupler on the rear car of the train coupled to the brake pipe. The SBT senses brake pipe pressure, and may sense motion and direction. This information is relayed by radio to the head end of the train to a RDU, CDU or a CLU/IDU combination. In addition, the SBT acts as a marker to indicate the rear of the train and is equipped with an emergency braking feature to be used in the event of a loss of the normal braking capability from the head end of the train.