Known as PTC, Positive Train Control is a complex signaling and communications technology that is designed to make commuter rail even safer.

PTC development and implementation is an unparalleled technological and financial challenge in scale, complexity, and time required.

PTC is a communications-intense technology that transmits data between trains and communications towers using wireless Internet, GPS, and encrypted radio transmissions. It requires tens of thousands of sensors to be installed on train tracks and locomotives; data centers to collect and analyze the data, and a train’s engine and braking system to be optimized as needed.

PTC utilizes a series of sensors and integrated monitoring systems that track key movement on trains and conditions on rail tracks in real time to identify potentially hazardous situations. If an unsafe speed situation arises, PTC automatically will trigger a train’s braking system to slow it and prevent an accident, such as a train-to-train collision.

Traveling by commuter rail and intercity rail is 18 times safer than traveling by automobile.

For the commuter rail industry, safety is more than just operating procedure. It’s a core value that guides our decisions. Commuter railroads work every day to continuously make safety improvements and constantly re-evaluate safety procedures as well as reinforcing a safety culture with employees.

Commuter and intercity rail have 0.36 passenger fatalities per billion passenger miles, compared with 6.53 passenger fatalities for automobiles or light trucks.

The Federal Railroad Administration’s Office of Safety Analysis reports that, of the more than 703 million passengers who travelled 110,541,557 miles on passenger rail systems in 2016, there were 267 recorded fatalities, most of whom were not train passengers but rather individuals trespassing on tracks.

According to the U.S. Department of Transportation’s National Highway Traffic Safety Administration, the 2016 U.S. road fatality rate was 1.18 per 100 million vehicle miles traveled, and 11.59 per 100,000 population.

The commuter railroads are 100 percent committed to implementing PTC to make our safe systems even safer.

According to the most recent data (September 2018), commuter railroads are making solid progress:

  • 100 percent of all needed radio spectrum has been acquired;
  • 96 percent of the 16,722 wayside installations have been completed;
  • 94 percent of 13,400 pieces of on-board equipment on locomotives and cab cars are PTC-installed;
  • 89 percent of back-office control systems are ready for operation;
  • 85 percent of 13,543 employees have been trained in PTC; and,
  • 68 percent of 28 commuter railroads are PTC operation, are in Revenue Service Demonstration (also called RSD), or are awaiting FRA approval to begin testing.

PTC serves as a redundancy that overlays with existing safety and signaling systems. PTC is designed to prevent:

  • Train-to-train collisions;
  • Over-speed derailments;
  • Incursions into established work zone limits; and
  • The movement of a train through a mainline switch in the improper position.

While Positive Train Control will prevent many types of incidents and will make our safe systems even safer, PTC will not prevent the following:

  • Grade-crossing collisions;
  • People trespassing on track;
  • Low-speed collisions from permissive block operation;
  • Track or train defect derailments;

In 2008, Congress passed the Rail Safety Improvement Act (RSIA) that required all commuter and freight railroads to implement PTC. In October 2015, the statutory deadline for PTC implementation was extended to 2020, provided that certain milestones were met and approved by the FRA by December 2018.

The required milestones, as defined in 49 U.S.C. 20157(a)(3)(B), are:

  • Install all PTC hardware (wayside and onboard equipment);
  • Acquire all necessary spectrum for PTC implementation;
  • Complete all employee training;
  • Initiate testing on at least one territory subject to the PTC requirement (or other criteria); and
  • Submit a plan and schedule to the Secretary of Transportation for implementing a PTC system.

Full implementation of PTC for publicly funded commuter railroads is estimated to be more than $4 billion. Additionally, that figure does not account for up to $130 million in annual future operating and maintenance costs.

The more than $4 billion cost of PTC comes on top of the existing $90 billion backlog needed to bring the national public transportation industry into a state of good repair. This is a major challenge for publicly funded transit systems in dire need of upgrades.

Since mandating PTC installation in 2008, the federal government has provided $435 million in PTC grants to commuter railroads, more than 80 percent ($360 million) of which was awarded only since May 2017.

Two commuter rail operators have also secured a total of $1.3 billion in federal loans to help pay for PTC installation. While this financing has been helpful, the burden of repaying these loans still falls on public agencies that already face significant financial pressures.

When PTC was mandated by Congress, the technology itself was only an idea – the rail industry has had to develop, test, and customize much of it before it could be installed. No, you can’t buy PTC at Best Buy!

Commuter railroads are making serious progress despite the challenges.

Early on, acquiring the actual radio transmission spectrum was a major hurdle, because of both the high costs and, in some cases, limited access.

The lack of experts and resources has prolonged the installation schedule. There are a limited number of people with the expertise needed to develop this complex technology and they are in high demand. Both commuter rail and freight railroads require the same vendors at the same time.

Interoperability is a major hurdle. Rail systems operate on a variety of tracks and systems that all need to be interoperable. Many railroads operate on tracks that they own or are hosted by freight railroads, or a combination of both. Each PTC system must be interoperable and seamlessly communicate with each other. All the trains, tracks, and the back-office of one railroad need to “talk” to trains, the track, and back-office of the other railroad.

In addition, commuter railroads must install and test PTC while simultaneously providing safe, consistent service to riders, who rely on daily service. In 2017 alone, commuter rail logged 501 million passenger trips traveling 11.75 billion miles.

There are 30 commuter railroads currently in the United States.

Three major options for PTC are described below:

ACSES
Advanced Civil Speed Enforcement System, (ACSES) is unique among PTC options as it is a vital rather than a non-vital overlay. First deployed on the Northeast Corridor in the 1990s, ACSES has been approved in a variety of different configurations throughout the Northeast. ACSES is also unique among PTC options in that it is transponder-based. The basic package functions as an overlay interfacing with an Automatic Train Control (ATC) system consisting of a Cab Signaling System (CSS) and a Speed Control System (SCS).

I-ETMS
Formerly known as Vital Electronic Train Management System, I-ETMS, or Interoperable Electronic Train Management System, is the second iteration of a PTC system originally​ pioneered by the former Burlington Northern Railroad on one of its single-track lines in Illinois used primarily for coal and grain traffic. This GPS and communications-based version of PTC was what was originally called for in the PTC mandate and has been the system of choice for at least five of the seven class-one freight railroads.

E-ATC
Electronic Automatic Train Control, (E-ATC) is the system of choice for most of the smaller commuter operations that do not run on Class I railroads. This is not interoperable with the Class I railroad systems, requiring dedicated equipment for its use.