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Positive Train Control (PTC) Overview (Railroad Safety)


Positive Train Control Overview


In 2008, Congress required railroads install Positive Train Control (PTC) on mainlines that transport any poisonous-inhalation-hazardous (PIH) materials and where regularly scheduled intercity passenger or commuter rail services are provided. PTC uses communication-based/processor-based train control technology that provides a system capable of reliably and functionally preventing train-to-train collisions, overspeed derailments, incursions into established work zone limits, and the movement of a train through a main line switch in the improper position. PTC is expected to be implemented over a total of approximately 70,000 miles of track.

In November 2015, Congress extended the originally PTC deadline (Dec. 31, 2015) to have PTC activated by three years to Dec. 31, 2018. Railroads were required to submit revised PTC implementation plans to FRA by Jan. 27, 2016, that outline how and when they will have PTC fully installed and activated. 

The Federal Railroad Administration (FRA) continues to support all rail carriers that have statutory reporting and installation requirements to implement PTC, as well as rail carriers that are continuing to voluntarily implement PTC. That assistance includes:

  • Providing more than $650 million to passenger railroads, including nearly $400 million in Recovery Act funding.
  • Issuing a nearly $1 billion loan to the Metropolitan Transportation Authority to implement PTC on the Long Island Rail Road and Metro-North.
  • Building a PTC testbed in Pueblo, Colorado.
  • Working directly with the Federal Communications Commission (FCC) and the Advisory Council on Historic Preservation to resolve issues related to spectrum use and improve the approval process for PTC communication towers.
  • Dedicating staff to continue work on PTC implementation in March 2010, including establishing a PTC task force.

Types of PTC Systems in the United States

ACSES (Advanced Civil Speed Enforcement System). A transponder-based system, in use on Amtrak's Northeast Corridor originally put into use on the Northeast Corridor by the specific requirements of an Order of Particular Applicability. (Type Approved and Certified by FRA.)

ETMS (Electronic Train Management System). A GPS- and communications-based system being deployed by BNSF Railway, originally put into use by the specific requirements of 49 CFR Part 236, Subpart H. (Type Approved and Certified by FRA for restricted use.)

I-ETMS (formerly called Vital Electronic Train Management System). A GPS- and communications-based system, not yet ready for deployment. It is the system of choice for CSX Transportation, Norfolk Southern Railway, and Union Pacific Railroad. BNSF Railway is to upgrade to it when software is available, various passenger/commuter and other railroads are adopting it for compatibility and interoperability. (Type Approved by FRA.)

ITCS (Incremental Train Control System). A GPS- and communications-based system used by Amtrak on its Michigan line, authorized for passenger train speeds up to 110 mph, originally put into use by the specific requirements of an FRA-approved waiver. ITCS certification through Amtrak's request for expedited certification process is pending successful resolution of a few remaining issues prior to FRA approval for certification.

Enhanced Automatic Train Control (E-ATC). A system that uses an underlying automatic train control (ATC) system, in conjunction with other “enhanced” features or systems to achieve the core required functionalities of PTC. These systems are often integrated with underlying cab signal systems (CSS) and centralized traffic control (CTC) systems, in addition to other signal or train control system enhancements the railroad elects to make,  to meet the full requirements of PTC.

Other Information

PTC Document Submission Railroads meeting the requirements for PTC implementation must submit for FRA approval various PTC-related documents. Those documents, redacted for public viewing to the extent determined necessary by the railroad, are available on under each railroad's PTC docket number.

Financial Assistance PTC systems are eligible for funding under the Railroad Rehabilitation and Improvement Financing Program; however; no railroads have approached FRA for funding of PTC projects using this program. PL110-432 has also authorized Railroad Safety Technology Grants that can be used to support PTC projects at $50 million per year from 2009 to 2013; however, the funds have not yet been appropriated. For further information contact: Mr. David Blackmore, PTC Branch Chief (312) 835-3903.

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