Positive Train Control (PTC)

Positive Train Control (PTC) is a predictive collision avoidance technology designed to stop a train before an accident occurs. The goals of PTC are to help prevent


Relying on sophisticated new technology, PTC is designed to keep a train under its maximum speed limit and within the limits of its authorization to be on a specific track.

Congress passed HP2095 "Rail Safety Improvement Act of 2008" in 2008 and president (G. Bush) signed its 315-pages requiring nationwide implementation of PTC by 2015. One region first. Initially it was to be developed in Los Angeles and made operational on Metrolink by 2012. Then in conjunctio for BNSF and UP freight railroads it was to be installed along their right-of-way in Southern California also by 2012.

Not surprisingly Congress didn't appropriate the funds even for first step in LA and southern CA. It assumed funds would come from individual RRs and local, state and federal funds. By the early 2010s we had outline of plan. But it was not to prevent accidents caused by

There are three elemenst of PTC to be integrated by a wireless commmunication sytem:

1. Onboard or Locomotive 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.

Current Progress

America's freight rail industry has been—-and remains—-committed to fully implementing PTC across America's freight rail network as quickly, safely and responsibly as possible.

To date, railroads have retained more than 2,400 signal system personnel to implement PTC and have already spent close to $6.5 billion on PTC development and deployment. They have developed new technologies from scratch and made considerable progress overcoming some of the biggest challenges associated with PTC, including geo-mapping nearly 60,000 miles for GPS guidance.

Note: None of the technology existed. In the years to come, ... Phased rollout is critical to saftey. No testinng software is avaiable. To support interoperability, RR are going to 220 MHz network. They are having problems acquiring the necessary amt of spectrun in the open market (esp. metropolitan area).

Data of progress is spotty. The two major freight lines--BNSR and CSX-- have installed technology on all locomotives (>15,000), have trained personnel on (non existing) technology, and made progress on field equipment -- along some 60,000 miles of RR right-of-way -- nearly 440,000 field assets (mileposts, curves, grade crossing, switches, signals, etc.) all geo-mapped.

Operating PTC lines

It is hard to tell what is installed. A common set of initals ACSES refers to advanced civil speed enforcement system strives to prevent train-to-train collisions, overspeeding, and protect work crews with temporary speed restrictions. Likewise ETS stands for electronic train management system provides a form of PTC in conjunction with train management and dispatch system (TMDS).

ATK (Amtrak) protect Michigan lines running at 110 mph.

BNSF has installed much of equipment and has segments operating.

KCS All US-based rail operations along KCS line (Kansas City) begun operating in Jan 2015.

MBTA Most Massachusetts communter locomotives and cab cars are equipped with PTC.

RTD PTC built into Denver's new commuter lines was set to open in 2016.

SEPTA Deleware Valley (Philadelphia metro line) is likely to have only commuter railroad in US to meet December 31, 2016 deadline on all of its commuter lines.

UP PTC installed on 120-mile segment of Union pacific.mps.ohio-state.edu track between Chicago and St. Louis.


Your comments and suggestions are appreciated.

To cite this page:

<http://www.physics.ohio-state.edu/~wilkins/energy/Resources/Lectures/PTC.html>
[Thursday, 14-Dec-2017 15:32:33 EST]
Edited by: wilkins@mps.ohio-state.edu on Wednesday, 05-Oct-2016 13:06:47 EDT