Track warrant
Encyclopedia
Track warrants are systematized permissions used on some railroad lines to authorize a train
's use of the main line. Dispatcher
s issue these permissions to train crews instead of using signals
. The crews receive track warrants by radio
, phone
, or electronic transmission from a dispatcher.
, and/or any fixed physical point, such as a switch
). The dispatcher may also issue time constraints (known as "Box 6" on a standard form), although the track warrants remain in effect until cleared by a member of the receiving crew. Track warrants are sometimes used in conjunction with a block signal system to provide rear-end protection against following trains.
Track warrants usually allow a train to move in one direction only--a "Proceed" instruction. Sometimes a train may also be given authorizing movements in either direction, called a "Work between" instruction. However, only one train can have a section of track at one particular time if moving in the same direction. If there are two trains moving in the same direction, the leading train must give up the track before the trailing train can obtain a track warrant for that territory. For example, if Train 56 has a track warrant to proceed in the northbound direction from MP (milepost) 14 to MP 77 and there is a train following, then Train 56 must give up a portion or all of its warrant before the following train can be issued the track that Train 56 has already cleared. Many times this is accomplished by the dispatcher asking the leading train for their milepost location and then issuing a warrant up to that point to the trailing train. Continuing the previous example, if Train 56 is clear of MP 50, the dispatcher can issue a warrant to the trailing train up to MP 50, but not beyond it. Once a train has received a new track warrant or has left track warrant territory they will release the entirety of their warrant back to the dispatcher.
Maintenance of Way crews receive track bulletins (usually called "Form A's", "Form B's" or "Form C's") in order to perform track work that would otherwise be interrupted by passing trains. This is done by providing the maintenance crew with a form or protection, or allowing work to be done behind a passing train.
as suggested by the General Code of Operating Rules
, consisting of several standard instructions to mark specific notes or conditions for a warrant. These vary from temporary speed restrictions to rules regarding meeting other trains.
Some railroad systems, such as Rail America, use additional boxes:
uses track warrants on its El Paso Subdivision which runs from Belen, New Mexico
to El Paso, Texas
, with the dispatcher in Fort Worth, Texas
. There are no electrical signals on the route. BNSF also uses TWC (Track Warrant Control) on its Forsyth Subdivision between Jones Jct. (a suburb of Billings, Montana
) and Hysham, Montana
. Unlike the El Paso Subdivision, ABS
is used. Some smaller Class II railroad
s, such as the Iowa Interstate Railroad
, and many Class III railroad
s are dispatched completely by track warrant.
Canadian railways use a similar system called Occupancy Control System (OCS), in which movements are controlled via clearances issued over the radio from the Rail Traffic Controller to the train. The system is in wide use on lines that aren't installed with centralized traffic control
(CTC).
Train
A train is a connected series of vehicles for rail transport that move along a track to transport cargo or passengers from one place to another place. The track usually consists of two rails, but might also be a monorail or maglev guideway.Propulsion for the train is provided by a separate...
's use of the main line. Dispatcher
Dispatcher
Dispatchers are communications personnel responsible for receiving and transmitting pure and reliable messages, tracking vehicles and equipment, and recording other important information...
s issue these permissions to train crews instead of using signals
Railway signal
A signal is a mechanical or electrical device erected beside a railway line to pass information relating to the state of the line ahead to train/engine drivers. The driver interprets the signal's indication and acts accordingly...
. The crews receive track warrants by radio
Two-way radio
A two-way radio is a radio that can both transmit and receive , unlike a broadcast receiver which only receives content. The term refers to a personal radio transceiver that allows the operator to have a two-way conversation with other similar radios operating on the same radio frequency...
, phone
Phone
Within phonetics, a phone is:* a speech sound or gesture considered a physical event without regard to its place in the phonology of a language* a speech segment that possesses distinct physical or perceptual properties...
, or electronic transmission from a dispatcher.
Operation
Track warrants are issued granting main track use between two named points (i.e. milepost sign, stationTrain station
A train station, also called a railroad station or railway station and often shortened to just station,"Station" is commonly understood to mean "train station" unless otherwise qualified. This is evident from dictionary entries e.g...
, and/or any fixed physical point, such as a switch
Railroad switch
A railroad switch, turnout or [set of] points is a mechanical installation enabling railway trains to be guided from one track to another at a railway junction....
). The dispatcher may also issue time constraints (known as "Box 6" on a standard form), although the track warrants remain in effect until cleared by a member of the receiving crew. Track warrants are sometimes used in conjunction with a block signal system to provide rear-end protection against following trains.
Track warrants usually allow a train to move in one direction only--a "Proceed" instruction. Sometimes a train may also be given authorizing movements in either direction, called a "Work between" instruction. However, only one train can have a section of track at one particular time if moving in the same direction. If there are two trains moving in the same direction, the leading train must give up the track before the trailing train can obtain a track warrant for that territory. For example, if Train 56 has a track warrant to proceed in the northbound direction from MP (milepost) 14 to MP 77 and there is a train following, then Train 56 must give up a portion or all of its warrant before the following train can be issued the track that Train 56 has already cleared. Many times this is accomplished by the dispatcher asking the leading train for their milepost location and then issuing a warrant up to that point to the trailing train. Continuing the previous example, if Train 56 is clear of MP 50, the dispatcher can issue a warrant to the trailing train up to MP 50, but not beyond it. Once a train has received a new track warrant or has left track warrant territory they will release the entirety of their warrant back to the dispatcher.
Maintenance of Way crews receive track bulletins (usually called "Form A's", "Form B's" or "Form C's") in order to perform track work that would otherwise be interrupted by passing trains. This is done by providing the maintenance crew with a form or protection, or allowing work to be done behind a passing train.
Standard instructions used in track warrants
Most track warrants in the U.S. follow a standard formForm (document)
A form is a document with spaces in which to write or select, for a series of documents with similar contents. The documents usually have the printed parts in common, possibly except for a serial number...
as suggested by the General Code of Operating Rules
General Code of Operating Rules
The General Code of Operating Rules is a set of operating rules for railroads in the United States. The GCOR is used by nearly every Class I railroad west of the Mississippi River, most of the Class II railroads, and many Short-line railroads....
, consisting of several standard instructions to mark specific notes or conditions for a warrant. These vary from temporary speed restrictions to rules regarding meeting other trains.
- Box 1. Void on a previous warrant.
- Box 2. Proceed from point to point.
- Box 3. Proceed from point to point (cont.)
- Box 4. Work between certain limits.
- Box 5. Not in effect until ____ .
- Box 6. Authority expires at ____ .
- Box 7. Not in effect until after the arrival of ____ at ____ .
- Box 8. Hold main track at last named point.
- Box 9. Do not foul limits ahead of ____ .
- Box 10. Clear main track at last named point.
- Box 11. Between ____ and ____ make all movements at restricted speed: limits occupied by train.
- Box 12. Between ____ and ____ make all movements at restricted speed: limits occupied by men or equipment.
- Box 13. Do not exceed ____ mph between _____ and ____ .
- Box 14. Do not exceed ____ mph between _____ and ____ .
- Box 15. Flag protection not required against following trains on same track.
- Box 16. Track bulletins in effect.
- Boxes 17 and 18: Other specific instructions.
Some railroad systems, such as Rail America, use additional boxes:
- Box 18. Joint with _____ between ____________ and _____________ .
- Box 19. Expect to find the following switch(es) lined and locked in the reverse position: _________ .
- Box 20. The following switch(es) may be left lined and locked in the reverse position: _________ .
Use of track warrants on specific railroads
The BNSF RailwayBNSF Railway
The BNSF Railway is a wholly owned subsidiary of Berkshire Hathaway Inc., and is headquartered in Fort Worth, Texas. It is one of seven North American Class I railroads and the second largest freight railroad network in North America, second only to the Union Pacific Railroad, its primary...
uses track warrants on its El Paso Subdivision which runs from Belen, New Mexico
Belen, New Mexico
Belen is a city in Valencia County, New Mexico, United States. Belen is Spanish for Bethlehem, and over time has gained the nickname "Hub City" because of the Belen Cutoff of the Atchison, Topeka and Santa Fe Railway. The Cutoff made it possible for many more trains to travel east and west across...
to El Paso, Texas
El Paso, Texas
El Paso, is a city in and the county seat of El Paso County, Texas, United States, and lies in far West Texas. In the 2010 census, the city had a population of 649,121. It is the sixth largest city in Texas and the 19th largest city in the United States...
, with the dispatcher in Fort Worth, Texas
Fort Worth, Texas
Fort Worth is the 16th-largest city in the United States of America and the fifth-largest city in the state of Texas. Located in North Central Texas, just southeast of the Texas Panhandle, the city is a cultural gateway into the American West and covers nearly in Tarrant, Parker, Denton, and...
. There are no electrical signals on the route. BNSF also uses TWC (Track Warrant Control) on its Forsyth Subdivision between Jones Jct. (a suburb of Billings, Montana
Billings, Montana
Billings is the largest city in the U.S. state of Montana, and is the principal city of the Billings Metropolitan Area, the largest metropolitan area in over...
) and Hysham, Montana
Hysham, Montana
Hysham is a town in and the county seat of Treasure County, Montana, United States. The population was 330 at the 2000 census.-Geography:Hysham is located at . According to the United States Census Bureau, the town has a total area of , all of it land.It is bordered to the north by the Yellowstone...
. Unlike the El Paso Subdivision, ABS
Automatic Block Signal
Automatic Block Signaling, or ABS, is a block system that consists of a series of signals that divide a railway line into a series of blocks and then functions to control the movement of trains between them through automatic signals...
is used. Some smaller Class II railroad
Class II railroad
A Class II railroad in the United States is a mid-sized freight-hauling railroad, in terms of its operating revenue. , a railroad with revenues greater than $20.5 million but less than $277.7 million for at least three consecutive years is considered a Class II railroad...
s, such as the Iowa Interstate Railroad
Iowa Interstate Railroad
The Iowa Interstate Railroad is a Class II railroad operating in the central United States. The railroad is owned by Railroad Development Corporation of Pittsburgh, Pennsylvania.-History:...
, and many Class III railroad
Class III railroad
A Class III railroad, as defined by the Surface Transportation Board, is a railroad with an annual operating revenue of less than $20 million . The term only applies to United States railroads, but is sometimes applied to other countries...
s are dispatched completely by track warrant.
Canadian railways use a similar system called Occupancy Control System (OCS), in which movements are controlled via clearances issued over the radio from the Rail Traffic Controller to the train. The system is in wide use on lines that aren't installed with centralized traffic control
Centralized traffic control
Centralized traffic control is a form of railway signalling that originated in North America and centralizes train routing decisions that were previously carried out by local signal operators or the train crews themselves. The system consists of a centralized train dispatcher's office that...
(CTC).
See also
- Dark territoryDark territoryDark territory is a term used in the North American railroad industry to describe a section of track not controlled by signals. Train movements in dark territory are controlled by track warrants or train order operation, with train dispatchers issuing orders by radio communication with train...
(North American terminology for unsignalled tracks) - Direct traffic controlDirect traffic controlDirect Traffic Control is a system for authorizing track occupancy used on some railroads instead of or in addition to signals. It is known as "direct" traffic control because the train dispatcher gives track authority directly to the train crew via radio, as opposed to through wayside personnel...
- Radio Electronic Token BlockRadio Electronic Token BlockRadio Electronic Token Block is a system of railway signalling used in the United Kingdom. It is a development of the physical token system for controlling traffic on single lines.- How it works :...
- Rail terminologyRail terminologyRail terminology is a form of technical terminology. The difference between the American term railroad and the international term railway is the most obvious difference in rail terminology...
- Train orderTrain orderTrain order operation, or more accurately Timetable and Train order operation, is a largely obsolete system by which the railroads of North America conveyed operating instructions before the days of centralized traffic control, direct traffic control, and the use of track warrants conveyed by radio...