Positive Train Control (PTC)

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    PTC is a system that will automatically stop a train if the engineer fails to obey a signal or exceeds the speed limit, thereby preventing train-to-train collisions, unauthorized entry into work zones and derailments due to speeding or moving through misaligned track switches. The system integrates GPS, trackside sensors and communications units, onboard computers and Metra’s centralized train dispatching system. Together, these components track trains, convey operating instructions and monitor the crew’s operation of the train.

    Installing PTC was a long, complex, expensive trip, but the work was completed by the yearend 2020 deadline and the result is an even safer system for riders.

    “Installing PTC was a huge technological, logistical and financial challenge, and we are incredibly proud of the work we have done to complete it on time,” said Metra CEO/Executive Director Jim Derwinski. “The reward is knowing we can now give our customers even greater confidence that our trains are as safe as they can be.”

    Why was PTC installed?

    After a commuter train-freight train collision that killed 25 people in Chatsworth, Calif., in 2008, Congress passed the Rail Safety Improvement Act, requiring railroads to install PTC. Under subsequent legislation, the work had to be done by the end of 2020.

    What did it cost?

    The final bill for implementation on Metra comes to about $415 million, money that for the most part had to be diverted from our already inadequate capital funding. Going forward, Metra expects PTC to cost about $20 million annually to operate and maintain.

    How did you do it?

    When PTC was mandated, it was not off-the-shelf technology that could be picked up from your local electronics store. It had to be designed from the ground up. The PTC software had to be customized to each railroad and its specific attributes. And because the entire industry pursued this project simultaneously, there were parts shortages, delays in acquiring radio spectrum and delays in delivering software updates. And Metra had to hire dozens of carmen, signalmen, signal engineers and others to design and install PTC.

    Why was it hard in Chicago?

    One of the main PTC challenges was “interoperability”: the requirement that any train operating over another railroad’s tracks must be able to communicate seamlessly with the back office of that railroad’s PTC system, in addition to its own system. Nowhere is that more difficult than Chicago, with its dense railroad network that operates 1,300 to 1,400 trains each day. Metra’s PTC system must work seamlessly with the PTC systems of 12 other railroad companies, and on one line alone – the SouthWest Service – it has to work with five.

    What’s next?

    Like most technologies, PTC is not a finished product. The software will continue to evolve adding functionality and improvements to operations, reliability, security, and maintenance.  We will also need to continually maintain and update the system’s hardware. And our train crews, dispatchers and field personnel on both mechanical and engineering will require time to understand and adjust to a new way of doing business.

    PTC by the Numbers

    $415 million Total installation cost
    $20 million Annual operating cost
    $11 billion Installation cost to railroad industry
    522 Locomotives, cab cars and Highliners equipped with components
    347 Wayside interface units installed
    12 Railroads that must be interoperable with Metra
    217.5 Miles of track mapped by Metra
    2,043 Employees trained