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Positive Train Control

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THE FACTS

PTC is a system of technologies that are designed to prevent certain types of train-related accidents — typically caused by human error — from occurring by automatically stopping the train.

The Rail Safety Improvement Act of 2008 required PTC systems to be fully implemented on Class I railroads by Dec. 31, 2015. The mandate would apply to all lines that transport poisonous or toxic-by-inhalation hazardous materials and any main lines with regularly scheduled intercity or commuter rail passenger service. The law mandated that railroads implement PTC systems that would be designed to prevent:

1. Train-to-train collisions
2. Overspeed derailments
3. Unauthorized incursions into established work zone limits
4. Movement of trains over improperly lined switches

In October 2015, Congress extended the deadline for full implementation to Dec. 31, 2018, while also allowing for the FRA to approve any further requests for extension with final deadline not later than Dec. 31, 2020. Prior to this deadline, Norfolk Southern achieved full implementation and interoperability across its entire PTC footprint.

 

THREE MAIN ELEMENTS INTEGRATED BY A WIRELESS COMMUNICATIONS SYSTEM MAKE UP A PTC SYSTEM.

PTC_infographic

1: Onboard System —Monitors the train’s position and speed and activates braking as necessary to enforce speed restrictions and unauthorized train movement into new sections of track.

2: Wayside System —Monitors railroad track signals, switches, and track circuits to communicate authorization for movement to the locomotive.

3: Back Office Server —The storehouse for all information related to the rail network and trains operating across it — speed limits, track composition, speed of individual locomotives, train composition, etc. — and transmits the authorization for individual trains to move into new segments of track.

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LOCOMOTIVES FULLY EQUIPPED AND OPERABLE
TRACK SEGMENTS COMPLETED
EMPLOYEES
TRAINED
TRACK/ROUTE
MILES IN PTC OPERATION
INTEROPERABLE

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$1.806B PTC investment.

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NS has installed 11,207 PIECES OF REQUIRED WAYSIDE HARDWARE
(3719 wayside antennas and 7488 wayside radios and WIUs.)

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NS locomotives are equipped with 5,800 PIECES OF REQUIRED PTC HARDWARE.

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NS TESTED OVER 20,500 SCENARIOS of PTC states and functions with more than 180 software iterations to validate the PTC System against requirements.

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More than HALF A BILLION MESSAGE TRANSACTIONS ARE GENERATED DAILY to keep the system operable and reliable.

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$1.806B PTC investment.

 

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NS has installed 11,207 PIECES OF REQUIRED WAYSIDE HARDWARE
(3719 wayside antennas and 7488 wayside radios and WIUs.)

 

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NS PTC MILESTONE TIMELINE

2020 – On schedule and ahead of the Dec. 31, 2020, deadline, PTC is fully implemented and interoperable on a footprint of more than 8,000 miles

2019 – NS initiates interoperable operations with CSX, CN, BNSF, and Virginia Railway Express

2019 – Federal Railroad Administration approves NS’ RFA to its conditionally approved PTC Safety Plan

2018 – Receives FRA approval for an alternative sequence and schedule, permitting full implementation of PTC in 2020

2018 – After successful testing on the Crescent route from Washington to New Orleans and the North Carolina and Virginia routes, NS initiates interoperable operations with Amtrak. Interoperability field testing is conducted with CSX, BNSF, and VRE.

2017 – NS contracts with TTCI and other railroads to perform an updated reliability study to assess system reliability, availability, and maintainability

2017 – Receives FRA conditional certification of the NS PTC system on May 19 and begins revenue service operations

2016 – Begins revenue service demonstration field tests in January; submits PTC Safety Plan to FRA in August

2015 – Completes comprehensive review of NS operating rules to ensure coordination with PTC system operation

2015 – Receives type approval from FRA for the I-ETMS system

2014 – Wayside tower construction resumes; field qualification testing on the first PTC district begins in August

2014 – Engages two nationally recognized firms to perform wide-ranging security assessments of the PTC system

2013 – Begins reviews of vendors’ testing processes and artifacts for releases of software products to assess variances from industry standards and best practices

2013 – At the direction of the Federal Communications Commission, wayside tower construction ceases pending resolution of a process for Tribal notification and consultation to address the agency’s compliance with the National Historic Preservation Act

2012 – Completes multi-year precision fly-mapping and data conversion for over 77,000 critical features on 16,100 rail miles for the construction of a highly accurate PTC track database

2012 – In consultation with the FRA, NS begins system safety case and risk assessment with safety consultants and Class I railroads

2011 – Begins field validation of wayside construction through disciplined signal cut-in procedures

2010 – Files first Implementation Plan and begins progressive implementation

2009 – Equips the first 150 locomotives for PTC

2008 – Rail Safety Improvement Act of 2008 becomes law

2008 – Work begins with Wabtec Railway Electronics to define a common PTC locomotive application with a common set of PTC functions to achieve interoperability

2008 – NS signs Interoperability Train Control Collaboration Agreement with industry partners

2005 – NS holds system design and implementation kickoff meeting for PTC years before Congressional Mandate


ADDITIONAL RESOURCES

PTC is the backbone of the future railroad, providing the pipeline and neural connections to unleash further automation technologies. Learn more about NS technology.


Association of American Railroads: https://www.aar.org/campaigns/ptc/
Federal Railroad Administration PTC Site: https://www.fra.dot.gov/ptc