![PTC, Metrolink 891, ARTIC, night](https://upload.wikimedia.org/wikipedia/commons/9/9e/PTC%2C_Metrolink_891%2C_ARTIC%2C_night.jpg)
Positive train control (PTC) is a family of
automatic train protection
Automatic train protection (ATP) is a type of train protection system which continually checks that the speed of a train is compatible with the permitted speed allowed by signalling, including automatic stop at certain signal aspects. If it is ...
systems deployed in the United States. Most of the United States'
national rail network
In United States railroading, the term national rail network, sometimes termed "U.S. rail network", refers to the entire network of interconnected standard gauge rail lines in North America. It does not include most subway or light rail lines. F ...
mileage has a form of PTC. These systems are generally designed to check that trains are moving safely and to stop them when they are not.
A simplistic form of train traffic governance is ''negative'' train control, where trains must stop when issued a stop order and can move in the absence of such. An example of negative train control is
Indusi. In contrast, ''positive'' train control restricts the train movement to an explicit allowance; movement is halted upon invalidation. A train operating under PTC receives a ''movement authority'' containing information about its location and where it is allowed to safely travel. As of 2019, the U.S. freight rail industry trade organization AAR claimed that the nation's largest freight railroads were operating PTC across 83.2 percent of the required route miles. The
(AREMA) describes positive train control systems as having these primary functions:
* Train separation or collision avoidance
* Line speed enforcement
* Temporary speed restriction enforcement
* Rail worker wayside safety
* Blind spot monitoring
History
Background
In the late 1980s, interest in train protection solutions heightened after a period of stagnant investment and decline following
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
. Starting in 1990, the US
National Transportation Safety Board
The National Transportation Safety Board (NTSB) is an independent U.S. government investigative agency responsible for civil transportation accident investigation. In this role, the NTSB investigates and reports on aviation accidents and incid ...
(
NTSB) counted
PTC (then known as positive train separation) among its "Most Wanted List of Transportation Safety Improvements."
[National Transportation Safety Board (NTSB), Washington, DC (2010)]
NTSB Most Wanted List; List of Transportation Safety Improvements after September 1990."">"Modifications to NTSB Most Wanted List; List of Transportation Safety Improvements after September 1990."
At the time, the vast majority of rail lines in US relied upon crew members to comply with all safety rules, and a significant fraction of accidents were attributable to human error, as evidenced in several years of official reports from the
FRA.
[FRA]
"Office of Safety Analysis Reports on Rail Accidents."
/ref>
In September 2008, the US Congress
A congress is a formal meeting of the representatives of different countries, constituent states, organizations, trade unions, political parties, or other groups. The term originated in Late Middle English to denote an encounter (meeting of a ...
considered a new law that set a deadline of 15 December 2015 for implementation of PTC technology across most of the US rail network. The bill, ushered through the legislative process by the Senate Commerce Committee
The United States Senate Committee on Commerce, Science, and Transportation is a standing committee of the United States Senate. Besides having broad jurisdiction over all matters concerning interstate commerce, science and technology policy, a ...
and the House Transportation and Infrastructure Committee
The U.S. House Committee on Transportation and Infrastructure is a standing committee of the United States House of Representatives.
History
The Committee on Transportation and Infrastructure was formerly known as the Committee on Public Works a ...
, was drafted in response to the collision
In physics, a collision is any event in which two or more bodies exert forces on each other in a relatively short time. Although the most common use of the word ''collision'' refers to incidents in which two or more objects collide with great fo ...
of a Metrolink passenger train
A passenger train is a train used to transport people along a railroad line. These trains may consist of unpowered passenger railroad cars (also known as coaches or carriages) hauled by one or more locomotives, or may be self-propelled; self pr ...
and a Union Pacific
The Union Pacific Railroad , legally Union Pacific Railroad Company and often called simply Union Pacific, is a freight-hauling railroad that operates 8,300 locomotives over routes in 23 U.S. states west of Chicago and New Orleans. Union Paci ...
freight train
Rail freight transport is the use of railroads and trains to transport cargo as opposed to human passengers.
A freight train, cargo train, or goods train is a group of freight cars (US) or goods wagons (International Union of Railways) haul ...
12 September 2008, in California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...
, which resulted in the deaths of 25 and injuries to more than 135 passengers.
As the bill neared final passage by Congress, the Association of American Railroads
The Association of American Railroads (AAR) is an industry trade group representing primarily the major freight Rail transport, railroads of North America (Canada, Mexico and the United States). Amtrak and some regional Commuter rail in North Am ...
(AAR) issued a statement in support of the bill. President George W. Bush
George Walker Bush (born July 6, 1946) is an American politician who served as the 43rd president of the United States from 2001 to 2009. A member of the Republican Party, Bush family, and son of the 41st president George H. W. Bush, he ...
signed the 315-page Rail Safety Improvement Act of 2008
The Rail Safety Improvement Act of 2008 is a United States federal law, enacted by Congress to improve railroad safety. Among its provisions, the most notable was the mandate requiring positive train control (PTC) technology to be installed on ...
into law on 16 October 2008.
Provisions of the law
Among its provisions, the law provides funding to help pay for the development of PTC technology, limits the number of hours freight rail crews can work each month, and requires the Department of Transportation to determine work hour limits for passenger train crews.
Implementation
To implement the law, the FRA published final regulations for PTC systems on 15 January 2010. The agency proposed amendments to its rules on 11 December 2012.[FRA (11 December 2012). "Positive Train Control Systems (RRR); Notice of proposed rulemaking". ''Federal Register.'' ]
In December 2010, the U.S. Government Accountability Office
The U.S. Government Accountability Office (GAO) is a legislative branch government agency that provides auditing, evaluative, and investigative services for the United States Congress. It is the supreme audit institution of the federal govern ...
(GAO) reported that Amtrak
The National Railroad Passenger Corporation, Trade name, doing business as Amtrak () , is the national Passenger train, passenger railroad company of the United States. It operates inter-city rail service in 46 of the 48 contiguous United Stat ...
and the major railroads have taken steps to install PTC systems under the law, but commuter rail
Commuter rail, or suburban rail, is a passenger rail transport service that primarily operates within a metropolitan area, connecting commuters to a central city from adjacent suburbs or commuter towns. Generally commuter rail systems are con ...
operators were not on track for the 2015 deadline. , only seven commuter systems (29 percent of those represented by APTA) were expecting to make the deadline. Several factors have delayed implementation, including the need to obtain funding (which was not provided by Congress); the time it has taken to design, test, make interoperable, and manufacture the technology; and the need to obtain radio spectrum along the entire rail network, which involves FCC permission and in some cases negotiating with an existing owner for purchase or lease.
The Metrolink commuter rail system in Southern California
Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural region that generally comprises the southern portion of the U.S. state of California. It includes the Los Angeles metropolitan area, the second most po ...
is planning to be the first US passenger carrier to install the technology on its entire system. After some delays, demonstration PTC in revenue service began in February 2014; the system is expected to be completed in late summer 2015.
In the Chicago metropolitan area
The Chicago metropolitan area, also colloquially referred to as Chicagoland, is a metropolitan area in the Midwestern United States. Encompassing 10,286 sq mi (28,120 km2), the metropolitan area includes the city of Chicago, its suburbs and hi ...
, the Metra
Metra is the commuter rail system in the Chicago metropolitan area serving the city of Chicago and its surrounding suburbs via the Union Pacific Railroad, BNSF Railway, and other railroads. The system operates 242 stations on 11 rail lines. I ...
system expected it will not be fully compliant with the PTC mandate until 2019.
In October 2015 Congress passed a bill extending the compliance deadline by three years, to 31 December 2018. President Barack Obama
Barack Hussein Obama II ( ; born August 4, 1961) is an American politician who served as the 44th president of the United States from 2009 to 2017. A member of the Democratic Party, Obama was the first African-American president of the U ...
signed the bill on 29 October 2015. Only four railroads met the December 2018 deadline; the other 37 got extensions to December 2020, which was allowed under the law for railroads that demonstrated implementation progress. On 29 December 2020, it was reported that the safeguards had been installed on all required railroads, two days ahead of the deadline.
Criticism
There is some controversy as to whether PTC makes sense in the form mandated by Congress. Not only is the cost of nationwide PTC installation expected to be as much as , most all of it borne by U.S. freight railroads, there are questions as to the reliability and maturity of the technology for all forms of mainline freight trains and high density environments. The PTC requirement could also impose startup barriers to new passenger rail or freight services that would trigger millions of dollars in additional PTC costs. The unfunded mandate In the United States, federal mandates are orders that induce "responsibility, action, procedure or anything else that is imposed by constitutional, administrative, executive, or judicial action" for state and local governments and/or the private se ...
also ties the hands of the FRA to adopt a more nuanced or flexible approach to the adoption of PTC technology where it makes the most sense or where it is technically most feasible.
While the FRA Rail Safety Advisory Committee identified several thousand "PPAs" (PTC preventable accidents) on US railroads over a 12-year period, cost analysis determined that the accumulated savings to be realized from all of the accidents was not sufficient to cover the cost of PTC across the railroads. Therefore, PTC was not economically justified at that time. The FRA concurred with this cost assessment in its 2009 PTC rulemaking document.
The reason behind the lack of economic justification is that the majority of accidents are minor and FRA crash worthiness standards help mitigate the potential loss of life or release of hazardous chemicals. For example, in the 20 years between 1987 and 2007, there were only two PTC-preventable accidents with major loss of life in the United States (16 deaths in the Chase, Maryland wreck (1987) and 11 in the Silver Spring, Maryland wreck (1996)), and in each case, the causes of the accidents were addressed through changes to operating rules.
The cost of implementing PTC on up to 25 commuter rail services in the United States has been estimated at over $2 billion and because of these costs, several services are having to cancel or reduce repairs, capital improvements, and service. Other services simply do not have the funds available for PTC and have deferred action assuming some change from Congress. Railroads that operate lines equipped with cab signalling
Cab signaling is a railway safety system that communicates track status and condition information to the cab, crew compartment or driver's compartment of a locomotive, railcar or multiple unit. The information is continually updated giving an ...
and existing Automatic Train Control
Automatic train control (ATC) is a general class of train protection systems for railways that involves a speed control mechanism in response to external inputs. For example, a system could effect an emergency brake application if the driver d ...
systems have argued that their proven track record of safety, which goes back decades, is being discounted because ATC is not as aggressive as PTC in all cases.
Basic operation
A typical PTC system involves two basic components:
* Speed display and control unit on the locomotive
* A method to dynamically inform the speed control unit of changing track or signal conditions.[Olson, R.T., Jr. (2007)]
"Incremental Train Control System On Amtrak's Michigan Line."
Presentation at AREMA Annual Conference, 9–12 September 2007, Chicago, IL.
Optionally, three additional components may exist:
* An on-board navigation system and track profile database to enforce fixed speed limits
* A bi-directional data link to inform signaling equipment of the train's presence
* Centralized systems to directly issue movement authorities to trains
PTC infrastructure
There are two main PTC implementation methods currently being developed. The first makes use of fixed signaling infrastructure such as coded track circuits and wireless transponders to communicate with the onboard speed control unit. The other makes use of wireless data radios spread out along the line to transmit the dynamic information. The wireless implementation also allows for the train to transmit its location to the signaling system which could enable the use of moving or "virtual" blocks. The wireless implementation is generally cheaper in terms of equipment costs, but is considered to be much less reliable than using "harder" communications channels. , for example, the wireless ITCS system on Amtrak's Michigan Line was still not functioning reliably after 13 years of development, while the fixed ACSES system has been in daily service on the Northeast Corridor
The Northeast Corridor (NEC) is an electrified railroad line in the Northeast megalopolis of the United States. Owned primarily by Amtrak, it runs from Boston through Providence, New Haven, Stamford, New York City, Philadelphia, Wilmington, a ...
since 2002 (''see'' Amtrak
The National Railroad Passenger Corporation, Trade name, doing business as Amtrak () , is the national Passenger train, passenger railroad company of the United States. It operates inter-city rail service in 46 of the 48 contiguous United Stat ...
, below).
The fixed infrastructure method is proving popular on high-density passenger lines where pulse code cab signaling has already been installed. In some cases, the lack of a reliance on wireless communications is being touted as a benefit.[Vogler, John (2005)]
Symposium on Positive Train Control Systems
The wireless method has proven most successful on low density, unsignaled dark territory
Dark territory is a term used in the North American railroad industry to describe a section of running track not controlled by signals. Train movements in dark territory were previously handled by timetable and train order operation, but since t ...
normally controlled via track warrant
A track warrant is a set of instructions issued to a train crew authorizing specific train movements. The system is widely used in North America. The warrant is issued by the train dispatcher and delivered to the train crew via radio. The train cr ...
s, where speeds are already low and interruptions in the wireless connection to the train do not tend to compromise safety or train operations.
Some systems, like Amtrak's ACSES, operate with a hybrid technology that uses wireless links to update temporary speed restrictions or pass certain signals, with neither of these systems being critical for train operations.
Locomotive speed control unit
The equipment on board the locomotive must continually calculate the train's current speed relative to a speed target some distance away governed by a braking curve. If the train risks not being able to slow to the speed target given the braking curve, the brakes are automatically applied and the train is immediately slowed. The speed targets are updated by information regarding fixed and dynamic speed limits determined by the track profile and signaling system.
Most current PTC implementations also use the speed control unit to store a database of track profiles attached to some sort of navigation system. The unit keeps track of the train's position along the rail line and automatically enforces any speed restrictions as well as the maximum authorized speed. Temporary speed restrictions can be updated before the train departs its terminal or via wireless data links. The track data can also be used to calculate braking curves based on the grade profile. The navigation system can use fixed track beacons or differential GPS stations combined with wheel rotation to accurately determine the train's location on the line within a few feet.
Centralized control
While some PTC systems interface directly with the existing signal system, others may maintain a set of vital computer systems at a central location that can keep track of trains and issue movement authorities to them directly via a wireless data network. This is often considered to be a form of Communications Based Train Control and is not a necessary part of PTC.
Trackside device interface
The train may be able to detect the status of (and sometimes control) wayside devices, for example switch
In electrical engineering, a switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. The most common type of ...
positions. This information is sent to the control center to further define the train's safe movements. Text messages and alarm conditions may also be automatically and manually exchanged between the train and the control center. Another capability would allow the employee-in-charge (EIC) to give trains permission to pass through their work zones via a wireless device instead of verbal communications.
Technical limitations
Even where safety systems such as cab signaling
Cab signaling is a railway safety system that communicates track status and condition information to the cab, crew compartment or driver's compartment of a locomotive, railcar or multiple unit. The information is continually updated giving an e ...
have been present for many decades, the freight railroad industry has been reluctant to fit speed control devices because the often heavy-handed nature of such devices can have an adverse effect on otherwise safe train operation. The advanced processor-based speed control algorithms found in PTC systems claim to be able to properly regulate the speed of freight trains over in length and weighing over , but concerns remain about taking the final decision out of the hands of skilled railroad engineer
A train driver, engine driver, engineman or locomotive driver, commonly known as an engineer or railroad engineer in the United States and Canada, and also as a locomotive handler, locomotive operator, train operator, or motorman, is a pers ...
s. Improper use of the air brake can lead to a train running away, derailment
In rail transport, a derailment occurs when a rail vehicle such as a train comes off its rails. Although many derailments are minor, all result in temporary disruption of the proper operation of the railway system and they are a potentially ...
or to an unexpected separation.
Furthermore, an overly conservative PTC system runs the risk of slowing trains below the level at which they had previously been safely operated by human engineers. Railway speeds are calculated with a safety factor
In engineering, a factor of safety (FoS), also known as (and used interchangeably with) safety factor (SF), expresses how much stronger a system is than it needs to be for an intended load. Safety factors are often calculated using detailed analy ...
such that slight excesses in speed will not result in an accident. If a PTC system applies its own safety margin, then the end result will be an inefficient double safety factor. Moreover, a PTC system might be unable to account for variations in weather conditions or train handling, and might have to assume a worst-case scenario
A worst-case scenario is a concept in risk management wherein the planner, in planning for potential disasters, considers the most severe possible outcome that can reasonably be projected to occur in a given situation. Conceiving of worst-case s ...
, further decreasing performance. In its 2009 regulatory filing, the FRA stated that PTC was in fact likely to decrease the capacity of freight railroads on many main lines. The European LOCOPROL/LOCOLOC project had shown that EGNOS
The European Geostationary Navigation Overlay Service (EGNOS) is a satellite-based augmentation system (SBAS) developed by the European Space Agency and EUROCONTROL on behalf of the European Commission. Currently, it supplements the GPS by rep ...
-enhanced satellite navigation alone was unable to meet the SIL4 safety integrity required for train signaling.[Rousseau, Michel, et al. (2004]
"LOCOLOC Project: Final Presentation."
Noordwijk, December 2004.
From a purely technical standpoint, PTC will not prevent certain low-speed collisions caused by permissive block operation, accidents caused by "shoving" (reversing with inadequate observation), derailments caused by track or train defect, grade crossing collisions, or collisions with previously derailed trains. Where PTC is installed in the absence of track circuit blocks, it will not detect broken rails, flooded tracks, or dangerous debris fouling the line.
Wireless implementations
Radio spectrum availability
The wireless infrastructure planned for use by all US freights, most small freight railroads, and many commuter railroads is based on data radios operating in a single frequency band near . A consortium created by two freight railroads called PTC 220 LLC has purchased significant spectrum around , from previous licensees for use in deploying PTC. Some of this spectrum is in the form of nationwide licenses and some is not. The consortium plans to make this spectrum available for use by the US freights, but has indicated as recently as 2011 that they are unsure if they have enough spectrum to meet their needs. Several commuter railroads have begun purchasing spectrum in their geographic areas, but there is widespread concern that the acquisition of enough spectrum may be difficult to accomplish because of a lack of availability, difficulties in negotiating complex multi-party deals to gain enough adjacent spectrum, and because the financial cost of the acquisitions may make the task impossible for some state agencies. However, research suggests that dynamic spectrum allocation can solve the spectrum allocation problem at 220 MHz bandwidth.
Many of the railroads have requested that the FCC reallocate parts of the spectrum to them. They argue that they must have spectrum to be interoperable with each other. The FCC has stated that there is no reallocation forthcoming, that the railroads are not justified in requesting spectrum reallocation because they have not quantified how much spectrum they need, and that the railroads should seek spectrum in the secondary markets or in other bands.
Radio band
There are no regulatory or technical requirements that demand that be used to implement PTC (if a PTC implementation is to use wireless components at all). If wireless data transmission is necessary, there are a few advantages to the spectrum, provided it can be acquired at a reasonable cost. The first reason to consider using spectrum is PTC interoperability for freights and for some, but not all, commuter rail operations. Freight operations in the US often include the sharing of railroad tracks where one railroad's rail vehicles operate as a guest on another railroad's host tracks. Implementing PTC in such an environment is most easily achieved by using the same PTC equipment, and this includes radios and the associated radio spectrum.
When a commuter railroad operation must operate on a freight railroad territory, the commuter will most likely be required to install PTC equipment (including a radio) on their rail vehicle that is compliant with the freight railroad's PTC system, and this generally means the use of radios and spectrum. If the commuter uses the same PTC equipment, radios, and spectrum on their own property, they will be able to use it when their vehicles travel onto a freight's territory. From a practical standpoint, if the commuter instead elects to use another type of PTC on their own property, they will need to install a second set of onboard equipment so they can operate PTC on their own property while also operating PTC on a freight's property. If a multi-band radio (such as the current generation software-defined radios) is not available, then separate radios and separate antennas will be necessary. With the complexity of track geometries, PTC requires a variable amount of the spectrum in a time critical manner. One way to achieve this is to extend the PTC software-defined radios, such that it has the intelligence to allocate the spectrum dynamically. Adding the intelligence to the radio also helps to improve the security of the PTC communication medium.
If a small freight or commuter railroad does not operate on another railroad territory, then there is no interoperability-based reason that obligates them to use spectrum to implement PTC. In addition, if a small freight or commuter railroad only operates on their own territory and hosts other guest railroads (freight or other passenger rail), there is still no interoperability-based reason the host is obliged to use spectrum to implement PTC. Such a railroad could implement PTC by freely picking any radio spectrum and requiring the guest railroads to either install compliant PTC equipment (including radios) on board their trains or provide wayside equipment for their guest PTC implementation to be installed on the host railroad property. An interesting case that highlights some of these issues is the northeast corridor. Amtrak operates services on two commuter rail properties it does not own: Metro-North Railroad
Metro-North Railroad , trading as MTA Metro-North Railroad, is a suburban commuter rail service run by the Metropolitan Transportation Authority (MTA), a New York State public benefit corporations, public authority of the U.S. state of New Yor ...
(owned by New York and Connecticut) and Massachusetts Bay Transportation Authority
The Massachusetts Bay Transportation Authority (abbreviated MBTA and known colloquially as "the T") is the public agency responsible for operating most public transportation services in Greater Boston, Massachusetts. The MBTA transit network in ...
(MBTA) (owned by Massachusetts). In theory, Amtrak could have found themselves installing their own PTC system on these host properties (about 15 percent of the corridor), or worse, found themselves in the ridiculous position of trying to install three different PTC systems on each Amtrak train to traverse the commuter properties. This was not the case. Amtrak had a significant head start over the commuter rail agencies on the corridor in implementing PTC. They spent a considerable amount of time in research and development and won early approvals for their ACSES system on the northeast corridor with the FRA. They chose first to use and then later moved to , in part because of a perceived improvement in radio-system performance and in part because Amtrak was using in Michigan for their ITCS implementation. When the commuter agencies on the corridor looked at options for implementing PTC, many of them chose to take advantage of the advance work Amtrak had done and implement the ACSES solution using . Amtrak's early work paid off and meant that they would be traversing commuter properties that installed the same protocol at the same frequency, making them all interoperable. (Actually most of the Northeast Corridor is owned and operated by Amtrak, not the commuter properties, including the tracks from Washington, D.C.
)
, image_skyline =
, image_caption = Clockwise from top left: the Washington Monument and Lincoln Memorial on the National Mall, United States Capitol, Logan Circle, Jefferson Memorial, White House, Adams Morgan, ...
to New York Penn Station
Pennsylvania Station, also known as New York Penn Station or simply Penn Station, is the main intercity railroad station in New York City and the busiest transportation facility in the Western Hemisphere, serving more than 600,000 passengers ...
and the tracks from Philadelphia to Harrisburg, Pennsylvania
Harrisburg is the capital city of the Commonwealth of Pennsylvania, United States, and the county seat of Dauphin County. With a population of 50,135 as of the 2021 census, Harrisburg is the 9th largest city and 15th largest municipality in Pe ...
. The State of Massachusetts owns the tracks from the Rhode Island state line to the New Hampshire state line, but Amtrak "operates" these lines. Only the line between New York City
New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the L ...
and New Haven, Connecticut
New Haven is a city in the U.S. state of Connecticut. It is located on New Haven Harbor on the northern shore of Long Island Sound in New Haven County, Connecticut and is part of the New York City metropolitan area. With a population of 134,02 ...
is actually owned and operated by a commuter line.)
One other perceived reason to consider for PTC may be PTC-compatible radio equipment availability. Radio equipment specifically targeted toward PTC is currently only available from a limited number of vendors, and they are focused only on . One radio vendor in particular, Meteorcomm LLC, is able to support the I-ETMS PTC protocol with a radio. Meteorcomm is jointly owned by several of the freights, and some in the industry have indicated that using their radio and associated equipment will be done on a per-site licensing basis. Recurring fees may be associated with this process too. There is further concern that the 'buy in' and licensing fees will be significant, and this has led some to speculate that the owners of Meteorcomm (the freights) may have legal exposure to anti-trust violations. For many railroads, there is no other practical option to meet the federal mandate than to install PTC at using I-ETMS with the Meteorcomm radios. On the northeast corridor, another radio vendor, GE MDS, is able to support the Amtrak ACSES protocol with a radio. It should be stressed that the main concern among the freights regarding the PTC deadline is the availability of PTC equipment. With an eye to anti-trust issues and ready radio availability, Meteorcomm radio designs have been second-sourced to CalAmp radios. This all may mean that there is not enough PTC radio equipment available for all of the railroads that must implement PTC.
There are also issues with the use of these frequencies outside the US; in Canada, remains part of the radioamateur 1.25-metre band.
Other bands besides will support PTC, and have been used to win approvals from the FRA for PTC. When Amtrak received their initial approval, they planned to use frequencies for ACSES. BNSF Railway
BNSF Railway is one of the largest freight railroads in North America. One of seven North American Class I railroads, BNSF has 35,000 employees, of track in 28 states, and nearly 8,000 locomotives. It has three transcontinental routes that ...
won its first PTC approvals from the FRA for an early version of ETMS using a multi-band radio that included frequencies, frequencies, frequencies and WiFi. A small freight or commuter that selects one or more of these bands or another one such as might find it easier to acquire spectrum. They will need to research spectrum issues, radio equipment, antennas, and protocol compatibility issues to successfully deploy PTC.
Interoperability requirements
There is no single defined standard for "interoperable PTC systems". Several examples of interoperable systems illustrate this point. First, the UP and BNSF are interoperable across their systems. They are both implementing I-ETMS and will use different radio frequencies in different locations. In the second example, Amtrak is interoperable with Norfolk Southern
The Norfolk Southern Railway is a Railroad classes, Class I freight railroad in the United States formed in 1982 with the merger of Norfolk and Western Railway and Southern Railway (U.S.), Southern Railway. With headquarters in Atlanta, the ...
in Michigan. Amtrak uses ITCS, while Norfolk Southern uses I-ETMS. To interoperate, two radios are installed in each wayside location and they both interface with a common PTC system through an interface device (similar to a network gateway or protocol converter) at each wayside location. One radio talks to freight trains using I-ETMS and one radio talks to passenger trains using ITCS. In this case interoperability stops at the wayside and does not include the wireless segment out to the rail vehicles or the onboard systems. In the third example, similar to the first, Metrolink, the commuter rail agency in Los Angeles, is implementing I-ETMS and will use the same PTC equipment as both the UP and BNSF. Metrolink is procuring their own spectrum so that trains on Metrolink territory (commuter and freight) will use other channels than those used by the UP and BNSF. Interoperability is achieved by directing the onboard radio to change channels depending on location. For SEPTA
The Southeastern Pennsylvania Transportation Authority (SEPTA) is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly 4 million people in five coun ...
, the commuter operation in and around Philadelphia
Philadelphia, often called Philly, is the largest city in the Commonwealth of Pennsylvania, the sixth-largest city in the U.S., the second-largest city in both the Northeast megalopolis and Mid-Atlantic regions after New York City. Sinc ...
, Ansaldo is implementing ACSES
Advanced Civil Speed Enforcement System (ACSES) is a positive train control cab signaling system developed by Alstom. The system is designed to prevent train-to-train collisions, protect against overspeed, and protect work crews with temporar ...
, the Amtrak northeast corridor PTC protocol. For CSX
CSX Transportation , known colloquially as simply CSX, is a Class I freight railroad operating in the Eastern United States and the Canadian provinces of Ontario and Quebec. The railroad operates approximately 21,000 route miles () of track. ...
all the ACSES PTC transactions will be handed to CSX at the SEPTA back office, and CSX will be responsible for deploying I-ETMS infrastructure that they will use to communicate with their freight trains. The SEPTA interoperability model is very similar to that of the public safety radio community wherein different radio systems that use different frequencies and protocols are cross-connected only in the back office to support system to system communications.
Multi-band solutions
For the major freight railroads and Amtrak the answer seems to be that one frequency band is sufficient. These rail operations measure on-time performance on a much more coarse scale than commuters do so their tolerance for delay is greater and has less impact on train schedules. In addition, the PTC implementations deployed by commuter operations will be running much closer to the performance envelope than that of either Amtrak or the freights. For commuters in particular there is therefore some concern that implementing PTC with a single frequency band may not be sufficient. The single frequency-band approach to supporting real-time train control has a history of being difficult to use for such applications. This difficulty is not unique to train control. Interference, both man-made and natural, can at times affect the operation of any wireless system that relies on one frequency band. When such wireless systems are employed for real-time control networks it is very difficult to ensure that network performance will not sometimes be impacted. CSX encountered this problem when it experienced propagation ducting problems in its Advanced Train Control System An Advanced Train Control System (ATCS) is a system of railway/railroad equipment designed to ensure safety by monitoring locomotive and train locations, providing analysis and reporting, automating track warrants
A track warrant is a set of ins ...
(ATCS) network in the 1990s. The ATCS protocol, which the AAR had recommended the FCC consider as PTC in 2000 (when AAR sought a nationwide "ribbon" license), can support train control operation at both and . The latter frequency band is only used for ATCS on a few subdivisions and shortlines. More recently, the industry had been moving toward a more robust multi-band radio solution for data applications such as PTC. In 2007, BNSF
BNSF Railway is one of the largest freight railroads in North America. One of seven North American Class I railroads, BNSF has 35,000 employees, of track in 28 states, and nearly 8,000 locomotives. It has three transcontinental routes that ...
first won FRA approval for their original ETMS PTC system using a multi frequency-band radio. In addition, in mid-2008, an FRA sponsored effort by the AAR to develop a Higher Performance Data Radio (HPDR) for use at actually resulted in a contract being awarded to Meteorcomm for a 4-band radio to be used for voice and data. These more recent multi-band radio efforts were shelved in late 2008, after the Rail Safety Improvements Act became law, and the freights decided to pursue PTC using alone, in a single frequency-band configuration. Amtrak and most commuter operations quickly followed suit, selecting .
Suitability of wireless PTC for commuter rail
Soon after the Rail Safety Improvements Act was passed, many commuter railroads chose not to develop their own PTC protocol and instead decided to save time and money by using a protocol developed for either freight or long haul passenger (Amtrak) operations. Deploying such a protocol for urban commuter operation, where it will be necessary to support numerous, small, fast-moving trains, will be a challenge. It remains to be seen whether the performance envelope of PTC protocols developed and optimized for less numerous, slower and/or larger trains can support a more complex operational scenario, such as that of a commuter rail operation, without impacting on-time performance. Detailed and exhaustive protocol simulation testing can ease the risk of problems, however, there are too many variables, especially when the wireless component is considered, to guarantee beforehand that under certain worst-case operational profiles in certain locations, train operations will not be impacted. In fact, during system acceptance testing, such worst-case operational profiles may not even be tested because of the effort involved. One need only consider what it would take to identify the PTC protocol train capacity limitations at each interlocking
In railway signalling, an interlocking is an arrangement of signal apparatus that prevents conflicting movements through an arrangement of tracks such as junction (rail), junctions or crossings. The signalling appliances and Track (rail transpor ...
of a large commuter rail operation when a train is broken down at the interlocking and 10–20 other trains are within communications range of a single wayside location. Such a what-if scenario may be tested at a few interlockings but not at the 30 or more interlockings on a large commuter property.
Open standards
A large group of industry experts from the federal government, manufacturers, railroads, and consultants are participating in a study group sponsored by the IEEE
The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operation ...
802.15 working group, to look at using lessons learned in protocol development in the IEEE 802
IEEE 802 is a family of Institute of Electrical and Electronics Engineers (IEEE) standards for local area networks (LAN), personal area network (PAN), and metropolitan area networks (MAN). The IEEE 802 LAN/MAN Standards Committee (LMSC) maintains ...
suite to propose a comprehensive solution to the wireless component of PTC. While this effort may not significantly change the current United States PTC efforts already underway, an open standard could possibly provide a way forward for all of the railroads to eventually deploy a more interoperable, robust, reliable, future-proof, and scalable solution for the wireless component of PTC.
Upgrade costs
The railroad industry, like the process industry and the power utility industry, has always demanded that the return on investment for large capital investments associated with infrastructure improvements be fully realized before the asset is decommissioned and replaced. This paradigm will be applied to PTC as well. It is highly unlikely that there will be any major upgrades to initial PTC deployments within even the first 10 years. The calculation for return on investment is not a simple one and some railroads may determine, for instance after five years, that an upgrade of certain components of PTC may be justified. An example could be the radio component of PTC. If an open standard creates a less expensive radio product that is backwards compatible to existing systems and that perhaps improves PTC system performance and also includes improvements that save on operational costs, then a railroad would be prudent to consider a plan for replacing their PTC radios.
Deployment
Alaska Railroad
Wabtec
Wabtec Corporation (derived from Westinghouse Air Brake Technologies Corporation) is an American company formed by the merger of the Westinghouse Air Brake Company (WABCO) and MotivePower Industries Corporation in 1999. It is headquartered ...
is working with the Alaska Railroad to develop a collision-avoidance, Vital PTC system, for use on their locomotives. The system is designed to prevent train-to-train collisions, enforce speed limits, and protect roadway workers and equipment. Wabtec's Electronic Train Management System, (ETMS) is also designed to work with the Wabtec TMDS dispatching system to provide train control and dispatching operations from Anchorage.
Data between locomotive and dispatcher is transmitted over a digital radio system provided by Meteor Communications Corp (Meteorcomm). An onboard computer alerts workers to approaching restrictions and to stop the train if needed.
Amtrak
Alstom
Alstom SA is a French multinational rolling stock manufacturer operating worldwide in rail transport markets, active in the fields of passenger transportation, signalling, and locomotives, with products including the AGV, TGV, Eurostar, Avelia ...
's and PHW's Advanced Civil Speed Enforcement System
Advanced Civil Speed Enforcement System (ACSES) is a positive train control cab signaling system developed by Alstom. The system is designed to prevent train-to-train collisions, protect against overspeed, and protect work crews with temporar ...
(ACSES) system is installed on parts of Amtrak's Northeast Corridor
The Northeast Corridor (NEC) is an electrified railroad line in the Northeast megalopolis of the United States. Owned primarily by Amtrak, it runs from Boston through Providence, New Haven, Stamford, New York City, Philadelphia, Wilmington, a ...
between Washington
Washington commonly refers to:
* Washington (state), United States
* Washington, D.C., the capital of the United States
** A metonym for the federal government of the United States
** Washington metropolitan area, the metropolitan area centered o ...
and Boston
Boston (), officially the City of Boston, is the state capital and most populous city of the Commonwealth of Massachusetts, as well as the cultural and financial center of the New England region of the United States. It is the 24th- mo ...
. ACSES enhances the cab signaling systems provided by PHW Inc. It uses passive transponders to enforce permanent civil speed restrictions. The system is designed to prevent train-to-train collisions (PTS), protection against overspeed and protect work crews with temporary speed restrictions.
GE Transportation Systems
GE Transportation is a division of Wabtec. It was known as GE Rail and owned by General Electric until sold to Wabtec on February 25, 2019. The organization manufactures equipment for the railroad, marine, mining, drilling and energy generati ...
' Incremental Train Control System (ITCS) is installed on Amtrak's Michigan line, allowing trains to travel at .
The 2015 Philadelphia train derailment could have been prevented had positive train control been implemented correctly on the section of track that train was travelling. The overspeed warning/penalty commands were not set up on that particular section of track although it was set up elsewhere.
Burlington Northern and Santa Fe (BNSF)
Wabtec
Wabtec Corporation (derived from Westinghouse Air Brake Technologies Corporation) is an American company formed by the merger of the Westinghouse Air Brake Company (WABCO) and MotivePower Industries Corporation in 1999. It is headquartered ...
's Electronic Train Management System, (ETMS) is installed on a segment of the BNSF Railway
BNSF Railway is one of the largest freight railroads in North America. One of seven North American Class I railroads, BNSF has 35,000 employees, of track in 28 states, and nearly 8,000 locomotives. It has three transcontinental routes that ...
. It is an overlay technology that augments existing train control methods. ETMS uses GPS
The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...
for positioning and a digital radio system to monitor train location and speed. It is designed to prevent certain types of accidents, including train collisions. The system includes an in-cab display screen that warns of a problem and then automatically stops the train if appropriate action is not taken.
CSXT
CSX Transportation
CSX Transportation , known colloquially as simply CSX, is a Class I freight railroad operating in the Eastern United States and the Canadian provinces of Ontario and Quebec. The railroad operates approximately 21,000 route miles () of track. ...
is developing a Communications-Based Train Management (CBTM) system to improve the safety of its rail operations. CBTM is the predecessor to ETMS.
Kansas City Southern (KCS)
Wabtec
Wabtec Corporation (derived from Westinghouse Air Brake Technologies Corporation) is an American company formed by the merger of the Westinghouse Air Brake Company (WABCO) and MotivePower Industries Corporation in 1999. It is headquartered ...
's Electronic Train Management System, (ETMS) will provide PTC solutions in conjunction with Wabtec
Wabtec Corporation (derived from Westinghouse Air Brake Technologies Corporation) is an American company formed by the merger of the Westinghouse Air Brake Company (WABCO) and MotivePower Industries Corporation in 1999. It is headquartered ...
's Train Management and Dispatch System (TMDS), which has served as KCS's dispatch solution since 2007, for all U.S. based rail operations along the KCS line. In January 2015, KCS began training personnel on PTC at its TEaM Training Center in Shreveport, La., with an initial class of 160 people.
Massachusetts Bay Transportation Authority (MBTA)
Most MBTA Commuter Rail locomotives and cab car
A control car, cab car (North America), control trailer, or driving trailer (UK and Ireland) is a non-powered rail vehicle from which a train can be operated. As dedicated vehicles or regular passenger cars, they have one or two driver compartm ...
s, except for the 1625–1652 series Bombardier control cars and the (now retired) 1000–1017 series F40PH locomotives, are equipped with the PTC compliant ACSES
Advanced Civil Speed Enforcement System (ACSES) is a positive train control cab signaling system developed by Alstom. The system is designed to prevent train-to-train collisions, protect against overspeed, and protect work crews with temporar ...
technology which is installed on the Amtrak Northeast Corridor
The Northeast Corridor (NEC) is an electrified railroad line in the Northeast megalopolis of the United States. Owned primarily by Amtrak, it runs from Boston through Providence, New Haven, Stamford, New York City, Philadelphia, Wilmington, a ...
. All MBTA trains traveling on any segment of the Northeast Corridor must be equipped with functioning ACSES onboard apparatus, which affects trains on Providence/Stoughton Line
The Providence/Stoughton Line is an MBTA Commuter Rail service in Massachusetts and Rhode Island, primarily serving the southwestern suburbs of Boston. Most service runs entirely on the Northeast Corridor between South Station in Boston and Prov ...
, Franklin Line
The Franklin Line, also called the Franklin/Foxboro Line, is part of the MBTA Commuter Rail system. It runs from Boston's South Station in a southwesterly direction toward Franklin, Massachusetts, utilizing the Northeast Corridor before splitti ...
and Needham Line routings. The MBTA will shut down some lines on weekends in 2017 and 2018 to meet a December 2020 federal deadline for full-system PTC.
Metropolitan Transportation Authority (MTA)
In November 2013 the New York Metropolitan Transportation Authority
The Metropolitan Transportation Authority (MTA) is a public benefit corporation responsible for public transportation in the New York City metropolitan area of the U.S. state of New York. The MTA is the largest public transit authority in th ...
signed a $428 million contract to install positive train control on the Long Island Rail Road and the Metro-North Railroad
Metro-North Railroad , trading as MTA Metro-North Railroad, is a suburban commuter rail service run by the Metropolitan Transportation Authority (MTA), a New York State public benefit corporations, public authority of the U.S. state of New Yor ...
to a consortium of Bombardier Transportation
Bombardier Transportation was a Canadian-German rolling stock and rail transport manufacturer, headquartered in Berlin, Germany.
It was one of the world's largest companies in the rail vehicle and equipment manufacturing and servicing industry ...
Rail Control Solutions and Siemens Rail Automation. The LIRR and Metro-North installations will include modifications and upgrades of the existing signal systems and the addition of ACSES
Advanced Civil Speed Enforcement System (ACSES) is a positive train control cab signaling system developed by Alstom. The system is designed to prevent train-to-train collisions, protect against overspeed, and protect work crews with temporar ...
II equipment. Siemens stated that the PTC installation will be completed by December 2015, but missed that deadline, and did not complete the installation until the end of 2020.
New Jersey Transit (NJT)
Ansaldo STS USA Inc's Advanced Speed Enforcement System (ASES) is being installed on New Jersey Transit
New Jersey Transit Corporation, branded as NJ Transit, and often shortened to NJT, is a state-owned public transportation system that serves the U.S. state of New Jersey, along with portions of New York State and Pennsylvania. It operates bu ...
commuter lines. It is coordinated with Alstom's ACSES so that trains can operate on the Northeast Corridor.
Norfolk Southern (NS)
Norfolk Southern Railway
The Norfolk Southern Railway is a Class I freight railroad in the United States formed in 1982 with the merger of Norfolk and Western Railway and Southern Railway. With headquarters in Atlanta, the company operates 19,420 route miles (31 ...
began work on the system in 2008 with Wabtec
Wabtec Corporation (derived from Westinghouse Air Brake Technologies Corporation) is an American company formed by the merger of the Westinghouse Air Brake Company (WABCO) and MotivePower Industries Corporation in 1999. It is headquartered ...
Railway electronics to start developing a plan implement Positive Train Control
Positive train control (PTC) is a family of automatic train protection systems deployed in the United States. Most of the United States' national rail network mileage has a form of PTC. These systems are generally designed to check that trains a ...
on NS rails. NS has already implemented PTC on 6,310 miles of track with plans to achieve it on 8,000 miles of track. NS has requested an extension on the time to have PTC active on its miles of track due to the need to work more on areas with no track signals, as well as making provisions for smaller railroads that the company does business with to be PTC capable. NS keeps experiencing issues with the system and wants to take the proper time to fix the system to ensure the safety of its employees and all others using their tracks. NS has been adding and updating its locomotives with PTC capable computers to allow those locomotives for use on mainlines. 2,900 locomotives out of the almost 4,000 the company has have been fitted with the PTC capable computers. NS plans to put at least 500 locomotives into storage using precision NS has been updating it trackside equipment such as radio towers and control point lighting to assist in PTC operations on the railroad. With the new computers on the locomotives it allows the locomotives to interact with each other and trackside systems. Norfolk Southern's General Electric
General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable energ ...
Transportation locomotives are equipped with GPS
The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...
to aid in the use of PTC. All of NS's locomotives are equipped with Energy Management a computer system that provides real time data on the locomotive. The system can also control train speed and brake systems on board. The EM system allows the locatives to use less fuel and be more efficient. NS's final goal is completely autonomous operations of their trains. This system will be used alongside Auto-router used to route train movements with little to no human interactions. With these two systems integrated with PTC it allows for more precise movement and train control across the railroad. NS, Union Pacific
The Union Pacific Railroad , legally Union Pacific Railroad Company and often called simply Union Pacific, is a freight-hauling railroad that operates 8,300 locomotives over routes in 23 U.S. states west of Chicago and New Orleans. Union Paci ...
, CSXT
CSX Transportation , known colloquially as simply CSX, is a Class I freight railroad operating in the Eastern United States and the Canadian provinces of Ontario and Quebec. The railroad operates approximately 21,000 route miles () of track. ...
, BNSF
BNSF Railway is one of the largest freight railroads in North America. One of seven North American Class I railroads, BNSF has 35,000 employees, of track in 28 states, and nearly 8,000 locomotives. It has three transcontinental routes that ...
, and Virginia Railway Express
Virginia Railway Express (VRE) is a commuter rail service that connects outlying small cities of Northern Virginia to Union Station in Washington, D.C. It operates two lines which run during weekday rush hour only: the Fredericksburg Line from ...
have been testing interoperation to make sure each companies PTC systems work with each other to ensure safe railroad travel. For this a NS train on CSXT
CSX Transportation , known colloquially as simply CSX, is a Class I freight railroad operating in the Eastern United States and the Canadian provinces of Ontario and Quebec. The railroad operates approximately 21,000 route miles () of track. ...
tracks has to act like a CSXT
CSX Transportation , known colloquially as simply CSX, is a Class I freight railroad operating in the Eastern United States and the Canadian provinces of Ontario and Quebec. The railroad operates approximately 21,000 route miles () of track. ...
train would or vice versa. That requires the railroads to use the same communications and radio frequencies for everything to operate smoothly. Nearly 3,000 locomotives have been fitted with the PTC capable computers.
Peninsula Corridor Joint Powers Board (Caltrain)
Caltrain
Caltrain (reporting mark JPBX) is a California commuter rail line serving the San Francisco Peninsula and Santa Clara Valley (Silicon Valley). The southern terminus is in San Jose at Tamien station with weekday rush hour service running as fa ...
's Communications Based Overlay Signal System (CBOSS) has been installed but not fully tested along the Peninsula Corridor between San Francisco, San Jose and Gilroy, California. Caltrain had selected Parsons Transportation Group (PTG), who had been working on a similar system for Metrolink in Southern California, to implement, install, and test CBOSS in November 2011. In February 2017, Caltrain's board canceled the contract with PTG for failure to meet the scheduled 2015 deadline. PTG and Caltrain would go on to file lawsuits for breach of contract. At its board of directors meeting on 1 March 2018, Caltrain announced that it will be awarding a contract to Wabtec for implementation of I-EMTS.
Regional Transportation District (RTD)
Positive Train Control (PTC) and vehicle monitoring system technologies have been developed for the Denver Metro Area's new commuter train lines that began opening in 2016. After the University of Colorado
The University of Colorado (CU) is a system of public universities in Colorado. It consists of four institutions: University of Colorado Boulder, University of Colorado Colorado Springs, University of Colorado Denver, and the University of Co ...
A Line opened on 22 April 2016 between Denver Union Station
Denver Union Station is the main railway station and central transportation hub in Denver, Colorado. It is located at 17th and Wynkoop Streets in the present-day LoDo district and includes the historic station house, a modern open-air train shed, ...
and Denver International Airport
Denver International Airport , locally known as DIA, is an international airport in the Western United States, primarily serving metropolitan Denver, Colorado, as well as the greater Front Range Urban Corridor. At , it is the largest airport in ...
, it experienced a series of issues related to having to adjust the length of unpowered gaps between different overhead power sections, direct lightning strikes, snagging wires, and crossing signals behaving unexpectedly. In response to the crossing issues, Denver Transit Partners, the contractor building and operating the A Line, stationed crossing guards at each place where the A line crosses local streets at grade, while it continued to explore software revisions and other fixes to address the underlying issues. The FRA required frequent progress reports, but allowed RTD to open its B Line as originally scheduled on 25 July 2016, because the B Line only has one at-grade crossing along its current route. However, FRA halted testing on the longer G Line to Wheat Ridge
The City of Wheat Ridge is a home rule municipality located in Jefferson County, Colorado, United States. Wheat Ridge is located immediately west of Denver and is a part of the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area. The ...
– originally scheduled to open in Fall 2016 – until more progress could be shown resolving the A Line crossing issues. G Line testing resumed in January 2018, though the A Line continued to operate under a waiver. The G Line opened to passenger service on 26 April 2019.
Sonoma-Marin Area Rail Transit (SMART)
Positive train control has been implemented at Sonoma–Marin Area Rail Transit
Sonoma–Marin Area Rail Transit (SMART) is a rail line and bicycle-pedestrian pathway project in Sonoma and Marin counties of the U.S. state of California. When completed, the entire system will serve a corridor between Cloverdale in north ...
's 63 crossings for the length of the initial passenger corridor which began regular service on 25 August 2017 after the FRA gave its final approval for SMART's PTC system. SMART uses the E-ATC system for its PTC implementation.
Southeastern Pennsylvania Transportation Authority (SEPTA)
SEPTA received approval from the FRA on 28 February 2016 to launch PTC on its Regional Rail
Regional rail, also known as local trains and stopping trains, are passenger rail services that operate between towns and cities. These trains operate with more stops over shorter distances than inter-city rail, but fewer stops and faster serv ...
lines. On 18 April 2016, SEPTA launched PTC on the Warminster Line
The Warminster Line is a route of the SEPTA Regional Rail commuter rail system. It serves stations between its namesake town, Warminster (SEPTA station), Warminster, and Center City, Philadelphia. Half of the route is shared by other lines, incl ...
, the first line to use the system.[ Over the course of 2016 and into 2017, PTC was rolled out onto different Regional Rail lines. On 1 May 2017, the ]Paoli/Thorndale Line
The Paoli/Thorndale Line, or R5 commonly known as the Main Line, is a SEPTA Regional Rail service running from Center City Philadelphia through Montgomery County and Delaware County to Thorndale in Chester County. It operates along the far eas ...
, Trenton Line
The Trenton Line is a route of the SEPTA Regional Rail (commuter rail) system. The route serves the northeastern suburbs of Philadelphia, Pennsylvania with service in Bucks County along the Delaware River to Trenton, New Jersey.
Route
Trenton L ...
, and Wilmington/Newark Line
The Wilmington/Newark Line is a route of the SEPTA Regional Rail commuter rail system in the Philadelphia area. The line serves southeastern Pennsylvania and northern Delaware, with stations in Marcus Hook, Pennsylvania, Wilmington, Delaware, and ...
(all of which run on Amtrak tracks) received PTC, the last of the Regional Rail lines to receive the system.
Southern California Regional Rail Authority (Metrolink)
Metrolink, the Southern California commuter rail system involved in the 2008 Chatsworth train collision that provided the impetus for the Rail Safety Improvement Act of 2008
The Rail Safety Improvement Act of 2008 is a United States federal law, enacted by Congress to improve railroad safety. Among its provisions, the most notable was the mandate requiring positive train control (PTC) technology to be installed on ...
, was the first passenger rail system to fully implement positive train control. In October 2010, Metrolink awarded a $120 million contract to PTG to design, procure, and install PTC. PTG designed a PTC system that used GPS technology informing position to on-board train computers, which communicate wirelessly with wayside signals and a central office. Metrolink anticipated placing PTC in revenue service by summer 2013. However, Parsons announced the FRA had authorized Metrolink to operate PTC RSD using Wabtec's I-ETMS in revenue service on the San Bernardino line in March 2015. Metrolink announced PTC had been installed on all owned right-of-way miles by June 2015, and was working to install the system on tracks shared with Amtrak, freight, and other passenger rail partners.
Union Pacific (UP)
In the 1990s, Union Pacific Railroad (UP) had a partnership project with General Electric
General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable energ ...
to implement a similar system known as "Precision Train Control." This system would have involved moving block
In railway signalling, a moving block is a signalling block system where the blocks are defined in real time by computers as safe zones around each train. This requires both knowledge of the exact location and speed of all trains at any given ti ...
operation, which adjusts a "safe zone" around a train based on its speed and location. The similar abbreviations have sometimes caused confusion over the definition of the technology. GE later abandoned the Precision Train Control platform.
In 2008, a team of Lockheed Martin
The Lockheed Martin Corporation is an American aerospace, arms, defense, information security, and technology corporation with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995. It ...
, Wabtec
Wabtec Corporation (derived from Westinghouse Air Brake Technologies Corporation) is an American company formed by the merger of the Westinghouse Air Brake Company (WABCO) and MotivePower Industries Corporation in 1999. It is headquartered ...
, and Ansaldo STS USA Inc installed an ITCS subsystem on a 120-mile segment of UP track between Chicago and St. Louis. Other major software companies, such as PK Global, Tech Mahindra
Tech Mahindra is an Indian multinational information technology services and consulting company. Part of the Mahindra Group, the company is headquartered in Pune and has its registered office in Mumbai. Tech Mahindra is a 6.0 billion company w ...
, are also some of the strategic IT partners in development of PTC systems.
As of 31 December 2017, Union Pacific Installed 99 percent, or more than 17,000 miles, of total route miles with PTC signal hardware. Union Pacific has partially installed PTC hardware on about 98 percent of its 5,515 locomotives earmarked for the same technology and have equipped and commissioned 4,220 locomotives with PTC hardware and software. Union Pacific has also installed 100 percent of the wayside antennas needed to support PTC along the company's right of way.
References
Further reading
Positive Train Control (PTC): Overview and Policy Issues
Congressional Research Service
The Congressional Research Service (CRS) is a public policy research institute of the United States Congress. Operating within the Library of Congress, it works primarily and directly for members of Congress and their committees and staff on a c ...
Positive Train Control: Additional Authorities Could Benefit Implementation"
Report to the Chairman, Committee on Commerce, Science, and Transportation, U.S. Senate, Government Accountability Office
The U.S. Government Accountability Office (GAO) is a legislative branch government agency that provides auditing, evaluative, and investigative services for the United States Congress. It is the supreme audit institution of the federal govern ...
"Communications-Based Signaling (CBS) – Vital PTC"
Paper presented at AREMA C&S Technical Conference 22 May 2007
"Integration and Alignment of PTC Track Data with Legacy Dispatch Data to Reduce PTC Implementation Cost and Safety Risks"
Paper presented at PTC World Congress 22 March 2016 Washington, D.C. Andrew Brant & Ken Xu
External links
"PTC: Meeting the Challenge and Getting it RIGHT"
(YouTube) – Freight Rail Works
{{Railwaysignalling, state=collapsed
Railway safety
Railway signalling block systems
Train protection systems