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{{Short description|A short length of track to release locomotives at terminal platforms}}
{{multiple issues|
{{more footnotes|date=September 2022}}
{{original research|date=September 2022}}
{{cleanup rewrite|date=September 2022}}
}}
[[File:Toyooka station (Hyogo prefecture) Miyazu line engine running track.jpg|thumb|Platform track and run-round loop at [[Toyooka Station (Hyōgo)|Toyooka Station]], Hyōgo, Japan, the terminus of the line from [[Miyazu Line|Miyazu]]]]A '''headshunt''' (or '''escape track''' in the [[United States]]) is a short length of [[Rail tracks|track]] provided to release [[locomotive]]s at [[Terminal station|terminal platforms]], or to allow [[Shunt (rail)|shunting]] to take place clear of main lines.
[[File:Toyooka station (Hyogo prefecture) Miyazu line engine running track.jpg|thumb|Platform track and run-round loop at [[Toyooka Station (Hyōgo)|Toyooka Station]], Hyōgo, Japan, the terminus of the line from [[Miyazu Line|Miyazu]]]]A '''headshunt''' (or '''escape track''' in the [[United States]]) is a short length of [[Rail tracks|track]] provided to release [[locomotive]]s at [[Terminal station|terminal platforms]], or to allow [[Shunt (rail)|shunting]] to take place clear of main lines.


==Terminal headshunt==
==Terminal headshunt==
[[File:Headshunt principle - end of line.svg|left|thumb|Principle of a terminal headshunt: <br />
[[File:Headshunt principle - end of line.svg|left|thumb|Sequence at a terminal headshunt: <br />
1. train arrives to the station <br />
1. train arrives at the station<br />
2. the engine is detached from the train and moves to the headshunt <br />
2. locomotive is detached from the train and moves into the headshunt <br />
3. locomotive reverses and the points are switched<br />
3. operations are made to reverse the engine's running direction (shifting between cabs...) <br />
4. the engine passes the cars using the passing loop <br />
4. locomotive travels along the passing loop to pass the cars<br />
5. locomotive reverses direction and the points are switched <br />
5. operations are made to reverse the engine's running direction (shifting between cabs...) <br />
6. the engine goes back to the cars <br />
6. locomotive couples to the opposite end of the train <br />
7. locomotive reverses and the train departs
7. operations are made to reverse the engine's running direction, couple the engine with the cars, and the train can move
]]
]]
A 'terminal headshunt' is a short length of track that allows a locomotive to uncouple from its train, move forward, and then run back past it on a parallel track. Such headshunts are typically installed at a [[terminal station]] to allow the locomotive of an arriving train to move to the opposite end of (in railway parlance, 'run around') its train, so that it can then haul the same train out of the station in the other direction (assuming, of course, that it is a locomotive equipped to run in either direction; for older, one-way equipment such as [[Steam locomotive|steam locomotives]] and [[Cab unit|cab unit locomotives]], a [[Wye (rail)|wye]] or [[Railway turntable|turntable]] needs to be provided to physically turn the engine around, as well as a run-around track).
A 'terminal headshunt' is a short length of track that allows a locomotive to uncouple from its train, move forward, and then run back past it on a parallel track. Such headshunts are typically installed at a [[terminal station]] to allow the locomotive of an arriving train to move to the opposite end of (in railway parlance, 'run around') its train so that it can then haul the same train out of the station in the other direction (assuming, of course, that it is a locomotive equipped to run in either direction; for locomotives that only operate in one direction, a [[Wye (rail)|wye]] or [[Railway turntable|turntable]] needs to be provided to physically turn the engine around, as well as a run-around track).


==Reversing headshunt==
==Reversing headshunt==
{{main article|Pocket track}}
[[File:Melbourne University tram stop shunting area, looking south, 2013 (1).JPG|thumb|[[Melbourne University tram stop]] has three reversing headshunts in succession, between the two running lines.]]
[[File:Melbourne University tram stop shunting area, looking south, 2013 (1).JPG|thumb|[[Melbourne University tram stop]] has three reversing headshunts in succession, between the two running lines.]]
Found primarily on [[metro system]]s, [[rapid transit]] [[light rail]] networks, and [[tram]]ways, a 'reversing headshunt' allows certain trains or trams to change direction, even on lines with high traffic flow, whilst others continue through the station. Typically there will be two running lines, one for each direction of travel, and the headshunt will be positioned between the two running lines, linked to both by [[points (rail)|points]]. Although most trains will pass through the station and continue in the same direction, an individual train may be directed into the reversing headshunt, before exiting onto the other running line, in the opposite direction of travel. This procedure allows a greater frequency of trains on a city-centre section of the line, and reduced frequency on the suburban sections, by allowing certain trains to shuttle back and forth only on the city centre part, using the reversing headshunts to change direction within the flow of trains.
Found primarily on [[metro system]]s, [[rapid transit]] [[light rail]] networks, and [[tram]]ways, a 'reversing headshunt' allows certain trains or trams to change direction, even on lines with high traffic flow, whilst others continue through the station.


==Shunting neck==
==Shunting neck==
<!-- [[Shunting neck]] redirects here. -->
<!-- [[Shunting neck]] redirects here. -->
The term headshunt may also refer to '''shunting neck''' or 'shunt spur': a short length of [[Rail tracks|track]] laid parallel to the main line for the purpose of allowing a train to shunt back into a [[Rail siding|siding]] or [[rail yard]] without occupying the main running-line.
The term headshunt may also refer to '''shunting neck''' or 'shunt spur': a short length of [[Rail tracks|track]] laid parallel to the main line to allow a train to shunt back into a [[Rail siding|siding]] or [[rail yard]] without occupying the main running-line.{{citation needed |date=September 2022}}


==Run round==
==Run round==
<!-- [[Run-round loop]] and [[Run-around loop]] redirect here. -->
<!-- [[Run-round loop]] and [[Run-around loop]] redirect here. -->
{{About|the track arrangement|heat recovery system|run around coil}}
{{About|section=yes|the track arrangement|heat recovery system|run around coil}}
[[File:Headshunt.png|thumb|450px|Diagram of a headshunt and run round loop]]
[[File:Headshunt.png|thumb|450px|Diagram of a headshunt and run round loop]]


Line 30: Line 37:
Although a common procedure for [[passenger train]]s when the majority of them were locomotive-hauled, the maneuver is now becoming rarer on public service railways.{{Citation needed|date=August 2009}} Increased use of [[multiple unit]] and [[Push-pull train|push-pull]] passenger services avoids the requirement for dedicated track and the need for railway staff to detach and reattach the locomotive at track level.{{Citation needed|date=August 2009}} However, on [[heritage railway]]s run-round loops are still usually more or less necessary at each end of the running line, partly because train services are usually locomotive-hauled, and partly because the run-round operation gives added interest to visitors. This practice is still very common on Intercity services in [[Victoria (Australia)|Victoria, Australia]].
Although a common procedure for [[passenger train]]s when the majority of them were locomotive-hauled, the maneuver is now becoming rarer on public service railways.{{Citation needed|date=August 2009}} Increased use of [[multiple unit]] and [[Push-pull train|push-pull]] passenger services avoids the requirement for dedicated track and the need for railway staff to detach and reattach the locomotive at track level.{{Citation needed|date=August 2009}} However, on [[heritage railway]]s run-round loops are still usually more or less necessary at each end of the running line, partly because train services are usually locomotive-hauled, and partly because the run-round operation gives added interest to visitors. This practice is still very common on Intercity services in [[Victoria (Australia)|Victoria, Australia]].


Runaround tracks are used in freight service in order to back cars into spurs. In this case the runaround track must be as long as the longest set of cars that would be pulled. The locomotive leaves the cars on the runaround track or the main line, goes around, and hooks up to the other end of the train. It can then reverse the cars into a spur.
Runaround tracks are used in [[freight rail]] service in order to back cars into spurs or to change directions to keep the locomotive at the front of the train for transport. In this case the runaround track must be as long as the longest set of cars that would be pulled. The locomotive leaves the cars on the runaround track or the main line, goes around, and hooks up to the other end of the train. It can then reverse the cars into a spur.


=== Examples ===
=== Examples ===
Stations which used to have run-rounds include:
Stations which used to have run-rounds include:
* United Kingdom
* UK
** [[Edinburgh Waverley railway station]]; The terminal platforms of this station featured locomotive release roads between two main platforms, connected by a [[Railroad switch#Three-way switch|three-way point]] to the crossover from each platform line.<ref>{{Cite web|url=https://maps.nls.uk/view/82877409#zoom=6&lat=6818&lon=2812&layers=BT|title=View map: Edinburghshire III.8 (Edinburgh) - Ordnance Survey 25 inch 2nd and later editions, Scotland, 1892-1949|website=maps.nls.uk}}</ref><ref>[https://maps.nls.uk/transport/railways/rec/8233 Edinburgh Waverley station - NBR Co. plan - published ca. 1898] - [https://maps.nls.uk/view/216546773#zoom=4&lat=5471&lon=11924&layers=BT zoomed in]</ref><ref>[https://maps.nls.uk/view/74415668 Edinburgh Waverley on OS town plan (1887) showing 3-way release crossover points between platforms]</ref><ref>[https://maps.nls.uk/view/74415762 Edinburgh Waverley on OS town plan (1894) showing 3-way release crossover points between platforms 2 & 3 and 4 & 5]</ref> The same arrangement of a three-way point on a central release road was also installed at the now closed stations:
*** [[Manchester Central railway station|Manchester Central]]<ref>[https://maps.nls.uk/view/231274368 Manchester Central on OS 1:500 town plan (1888) showing 3-way release crossover points between platforms 1 & 2, 3 & 4 and 5 & 6]</ref><ref>[https://maps.nls.uk/view/126522839#zoom=6&lat=7032&lon=11055&layers=BT Manchester Central station - Ordnance Survey 25" to the mile - published 1934]</ref><ref>[http://www.disused-stations.org.uk/m/manchester_central/index33.shtml Manchester Central station looking towards the buffer stops] ([http://www.disused-stations.org.uk/ Disused Stations in the UK])</ref><ref>[http://www.disused-stations.org.uk/m/manchester_central/index43.shtml Manchester Central station from the buffer stops] ([http://www.disused-stations.org.uk/ Disused Stations in the UK])</ref>
*** [[Liverpool Exchange railway station|Liverpool Exchange]]<ref>[http://www.disused-stations.org.uk/l/liverpool_exchange/index.shtml 1864 - 1:500 town plan] ([http://www.disused-stations.org.uk/ Disused Stations])</ref><ref>[https://maps.nls.uk/view/229948701 Liverpool Exchange on OS 1:500 town plan (1890) showing 3-way release crossover points between platforms 4 & 5]</ref><ref>Preston Hendry, R., Powell Hendry, R., (1982) ''An historical survey of selected LMS stations : layouts and illustrations. Vol. 1'' Oxford Publishing</ref>
*** [[Leeds Central railway station|Leeds Central]]<ref>[[c:File:Leeds Central Station geograph-2334667-by-Ben-Brooksbank.jpg|Leeds Central station from the buffer stops showing 3-way point for release crossovers]]</ref><ref>[https://maps.nls.uk/view/229947285 Leeds Central on OS 1:500 town plan (1910) showing 3-way release crossover points between platforms 2 & 3]</ref>
** [[St Ives railway station]]
** [[St Ives railway station]]
** [[Matlock Riverside railway station]], now closed
** [[Matlock Riverside railway station]], now closed
** [[Birmingham Moor Street railway station|Birmingham Moor Street]]. This station is on a confined site, so to save space the platform lines were equipped with [[Transfer table|traversers]] to allow locomotives to run round via the adjacent platform line (platforms 1 & 2) or an adjacent loop (platform 3).<ref name=WARR>{{cite web|title=Moor Street Passenger Station|url=http://www.warwickshirerailways.com/gwr/moorstreet.htm|website=Warwickshirerailways.com|access-date=24 March 2013}}</ref><ref>{{cite web|url=http://www.warwickshirerailways.com/gwr/gwrms1223.htm|title=Moor Street Station: Ex-GWR 2-6-2T 'Prairie' No 6152 is seen standing on the traverser as it is being moved from platform 2 to platform 1 on the right|website=Warwickshirerailways.com}}</ref><ref>[https://www.warwickshirerailways.com/gwr/gwrms1735.htm A locomotive at Moor Street being transferred to the run round loop for platform 3] (Warwickshirerailways.com)</ref>
** [[Withernsea railway station|Withernsea]], the terminal station on the now closed [[Hull and Holderness Railway]]. At this station, instead of a [[Railroad switch|crossover or points]] the run round loop was accessed from a [[Railway turntable|turntable]] at the end of the platform line and run round loop.<ref>{{cite web|url=http://www.disused-stations.org.uk/enwiki/w/withernsea/index.shtml|title=Station Name: Withernsea|date=19 April 2019|work=Disused Stations|publisher=Subterranea Britannica|accessdate=8 March 2022}}</ref><ref>[http://www.disused-stations.org.uk/enwiki/w/withernsea/index1.shtml 1891 1:2,500 OS map showing the layout of Withernsea station] ([http://www.disused-stations.org.uk/ Disused Stations in the UK])</ref> There was a similar arrangement at [[Ventnor railway station|Ventnor]] and [[Bembridge railway station|Bembridge]] railway stations on the [[Isle of Wight Railway|Isle of Wight]].
<gallery captions="Turntable and run round loop at Withernsea">
File:Withernsea Railway Station.jpg|Turntable and run round loop at Withernsea
File:Leeds Central Station geograph-2334667-by-Ben-Brooksbank.jpg|Leeds Central station showing the release crossovers
</gallery>
* Australia
* Australia
** [[Murwillumbah railway station]], now closed
** [[Murwillumbah railway station]], now closed
Line 44: Line 61:


Stations which still have run-rounds include:
Stations which still have run-rounds include:
* United Kingdom
* UK
** [[Weymouth railway station]]
** [[Weymouth railway station]]
** [[Fort William railway station]]
** [[Fort William railway station]]
Line 79: Line 96:


== No loop ==
== No loop ==
If a terminal station has or no longer has a run-round loop, trains are restricted to multiple units or [[Top and Tail]] trains.
If a terminal station does not have a run-round loop trains are restricted to multiple units or [[Top and Tail]] trains.{{citation needed |date=September 2022}}


== Relay engines ==
==See also==
*[[Backshunt]]
Sometimes a terminal station has no run-round loops, the absence of which is overcome by coupling a relay engine to the rear to power the next out bound trip. The original engine of the arriving train shunts to the relay engine siding where it awaits the arrival of the second train, and so on. Examples in steam days include [[Fenchurch Street railway station|Fenchurch Street]] and [[Kingsgrove]].


== References ==
== References ==

Latest revision as of 20:06, 11 November 2024

Platform track and run-round loop at Toyooka Station, Hyōgo, Japan, the terminus of the line from Miyazu

A headshunt (or escape track in the United States) is a short length of track provided to release locomotives at terminal platforms, or to allow shunting to take place clear of main lines.

Terminal headshunt

[edit]
Sequence at a terminal headshunt:
1. train arrives at the station
2. locomotive is detached from the train and moves into the headshunt
3. locomotive reverses and the points are switched
4. locomotive travels along the passing loop to pass the cars
5. locomotive reverses direction and the points are switched
6. locomotive couples to the opposite end of the train
7. locomotive reverses and the train departs

A 'terminal headshunt' is a short length of track that allows a locomotive to uncouple from its train, move forward, and then run back past it on a parallel track. Such headshunts are typically installed at a terminal station to allow the locomotive of an arriving train to move to the opposite end of (in railway parlance, 'run around') its train so that it can then haul the same train out of the station in the other direction (assuming, of course, that it is a locomotive equipped to run in either direction; for locomotives that only operate in one direction, a wye or turntable needs to be provided to physically turn the engine around, as well as a run-around track).

Reversing headshunt

[edit]
Main article: Pocket track
Melbourne University tram stop has three reversing headshunts in succession, between the two running lines.

Found primarily on metro systems, rapid transit light rail networks, and tramways, a 'reversing headshunt' allows certain trains or trams to change direction, even on lines with high traffic flow, whilst others continue through the station.

Shunting neck

[edit]

The term headshunt may also refer to shunting neck or 'shunt spur': a short length of track laid parallel to the main line to allow a train to shunt back into a siding or rail yard without occupying the main running-line.[citation needed]

Run round

[edit]
This section is about the track arrangement. For heat recovery system, see run around coil.
Diagram of a headshunt and run round loop

A run round loop (or run-around loop) is a track arrangement that enables a locomotive to attach to the opposite end of the train. It is commonly used to haul wagons onto a siding, or at a terminal station to prepare for a return journey.[1] This process is known as "running round a train".[2]

Although a common procedure for passenger trains when the majority of them were locomotive-hauled, the maneuver is now becoming rarer on public service railways.[citation needed] Increased use of multiple unit and push-pull passenger services avoids the requirement for dedicated track and the need for railway staff to detach and reattach the locomotive at track level.[citation needed] However, on heritage railways run-round loops are still usually more or less necessary at each end of the running line, partly because train services are usually locomotive-hauled, and partly because the run-round operation gives added interest to visitors. This practice is still very common on Intercity services in Victoria, Australia.

Runaround tracks are used in freight rail service in order to back cars into spurs or to change directions to keep the locomotive at the front of the train for transport. In this case the runaround track must be as long as the longest set of cars that would be pulled. The locomotive leaves the cars on the runaround track or the main line, goes around, and hooks up to the other end of the train. It can then reverse the cars into a spur.

Examples

[edit]

Stations which used to have run-rounds include:

  • Turntable and run round loop at Withernsea
    Turntable and run round loop at Withernsea
  • Leeds Central station showing the release crossovers
    Leeds Central station showing the release crossovers

Stations which still have run-rounds include:

No loop

[edit]

If a terminal station does not have a run-round loop trains are restricted to multiple units or Top and Tail trains.[citation needed]

See also

[edit]

References

[edit]
  1. ^ Jackson, Alan A. (2006). The Railway Dictionary (4th ed.). Sutton Publishing Ltd. p. 298. ISBN 0-7509-4218-5.
  2. ^ Ellis, Iain (2006). Ellis' British Railway Engineering Encyclopaedia. Lulu.com. p. 307. ISBN 978-1-8472-8643-7.
  3. ^ "View map: Edinburghshire III.8 (Edinburgh) - Ordnance Survey 25 inch 2nd and later editions, Scotland, 1892-1949". maps.nls.uk.
  4. ^ Edinburgh Waverley station - NBR Co. plan - published ca. 1898 - zoomed in
  5. ^ Edinburgh Waverley on OS town plan (1887) showing 3-way release crossover points between platforms
  6. ^ Edinburgh Waverley on OS town plan (1894) showing 3-way release crossover points between platforms 2 & 3 and 4 & 5
  7. ^ Manchester Central on OS 1:500 town plan (1888) showing 3-way release crossover points between platforms 1 & 2, 3 & 4 and 5 & 6
  8. ^ Manchester Central station - Ordnance Survey 25" to the mile - published 1934
  9. ^ Manchester Central station looking towards the buffer stops (Disused Stations in the UK)
  10. ^ Manchester Central station from the buffer stops (Disused Stations in the UK)
  11. ^ 1864 - 1:500 town plan (Disused Stations)
  12. ^ Liverpool Exchange on OS 1:500 town plan (1890) showing 3-way release crossover points between platforms 4 & 5
  13. ^ Preston Hendry, R., Powell Hendry, R., (1982) An historical survey of selected LMS stations : layouts and illustrations. Vol. 1 Oxford Publishing
  14. ^ Leeds Central station from the buffer stops showing 3-way point for release crossovers
  15. ^ Leeds Central on OS 1:500 town plan (1910) showing 3-way release crossover points between platforms 2 & 3
  16. ^ "Moor Street Passenger Station". Warwickshirerailways.com. Retrieved 24 March 2013.
  17. ^ "Moor Street Station: Ex-GWR 2-6-2T 'Prairie' No 6152 is seen standing on the traverser as it is being moved from platform 2 to platform 1 on the right". Warwickshirerailways.com.
  18. ^ A locomotive at Moor Street being transferred to the run round loop for platform 3 (Warwickshirerailways.com)
  19. ^ "Station Name: Withernsea". Disused Stations. Subterranea Britannica. 19 April 2019. Retrieved 8 March 2022.
  20. ^ 1891 1:2,500 OS map showing the layout of Withernsea station (Disused Stations in the UK)
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