positive train control system
Defined in 1 dictionary — U.S. Code
United States Code
49 U.S.C. § 20157 — in this section (2 versions over time)
The term “positive train control system” means a system designed to prevent train-to-train collisions, over-speed derailments, incursions into established work zone limits, and the movement of a train through a switch left in the wrong position.