Patent ID: 7949441

Claim:
A method for controlling a level of tractive effort in a train having a first locomotive constituting a command locomotive, operable through a range of engine power settings, and a second locomotive positioned in the train at a spaced location from the command locomotive, said second locomotive constituting a command-follower locomotive, operable through a range of engine power settings, with at least one railcar being positioned between the command and command-follower locomotives, a communication link between the command and command-follower locomotives for transmitting and receiving engine power control signals for controlling locomotive engine power settings and tractive effort control signals for controlling the level of tractive effort, and at least one of the locomotives being configured to selectively operate in either of two modes of operation comprising a first mode in which said at least one locomotive generates a different tractive effort than when said at least one locomotive is in a second mode of operation, the method comprising; at the command locomotive selecting between the two modes of operation for producing a level of tractive effort appropriate for conditions as the train moves along a length of track; transmitting a tractive effort control signal indicative of the selected mode of operation; receiving the tractive effort control signal at another of said locomotives; and controlling the tractive effort generated at said at least one locomotive so as to develop a differential in the tractive effort generated by the command and command-follower locomotives, with the tractive effort generated at the command locomotive being different than that generated at the command-follower locomotive, in one of the two modes of operation, whereby with the command and command-follower locomotives under power to operate in engine power settings to move the train in a given direction of travel, the differential in the tractive effort generated by the command and command-follower locomotives is selected to avoid an occurrence of a derailment condition that otherwise can develop in a railcar between the command and command-follower locomotives.