Talk:Spiral (railway)

Spirals on light-rail lines
"Spirals are not generally used on tramways (street running or reserved track) or light rail lines because trams traditionally have all wheels powered, so can climb much steeper direct gradients than railways."


 * Maybe, but they're not unheard of. At Gateway/NE 99th Transit Center in Portland, OR, TriMet's MAX light rail trains to and from Portland International Airport make a loop in order to avoid having to reverse at the station. 4.243.146.54 06:55, 22 February 2007 (UTC)

Lead image
Would there be any support for replacing this diagram with this equally informative photograph, now rather incongruously adorning the "roads" section, in the lead? AFAIR the photograph was not available when the .png was made for the article. --Old Moonraker (talk) 15:36, 16 June 2008 (UTC)
 * No support then, but no opposition either. I'll get on with it. --Old Moonraker (talk) 22:19, 18 June 2008 (UTC)

Sri Lanka
Would a "famous loop" at Demodera be a spiral?

Tabletop (talk) 23:09, 1 October 2008 (UTC)

Slovakia
I edited the spelling of the page name. The correct Slovak spelling is "slučka", not "sľučka". Dictionary reference: http://slovnik.juls.savba.sk/?w=slucka&s=exact&d=kssj4&d=psp&d=ma&d=scs&d=sss&d=peciar&d=hssjV&d=obce&d=priezviska&ie=utf-8&oe=utf-8 —Preceding unsigned comment added by 78.99.214.40 (talk) 15:45, 30 May 2009 (UTC)

A loop in Mexico
There is a loop on the Chihuahua al Pacifico railroad between Las Mochis and Chihuahua.

It can be seen at http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=27.6546327N+107.7387035W&aq=&sll=37.0625,-95.677068&sspn=53.564699,114.169922&ie=UTF8&ll=27.654015,-107.737856&spn=0.007394,0.013937&t=h&z=17

It is also referenced at http://en.wikipedia.org/wiki/Chihuahua_al_Pacifico

I'll leave it to you railroad buffs to fill in the details... — Preceding unsigned comment added by Alweiss (talk • contribs) 18:54, 12 April 2011 (UTC)

Cannot find Altare loop in Italy and only two loops on the Kenya - Uganda line
Please double check and change. The Mexico loop above seems OK. Tord Björk (talk) 02:21, 15 January 2013 (UTC)

Proposed Norway Removal
I have been editing this page by trying to provide further references. I am having difficulty in supporting the existence of the Norwegian spirals:
 * Flåm Line: between Myrdal and Flåm – tunnels that spiral in and out of the mountainside.
 * Rauma Line: near the Kylling Bridge

The Wikipedia page for the line Flåm Line doesn't mention a spiral but does mention a horseshoe curve, it's hard to tell on Open Street Map, it may not be as accurate as other sources, Google maps doesn't show a spiral but is quite inaccurate anyway , Bing maps doesn't show a spiral either.

I do have some links that show the railway near Kylling Bridge as a series of horseshoe bends but not a spiral, they are: The Wikipedia page at Kylling Bridge, Open Street Map , Google maps , Bing maps and a reference from a book

Unless I hear from someone who knows that these spirals exist and can provide a suitable references I propose to remove the Norwegian entry

Colinlangdon (talk) 11:45, 29 June 2016 (UTC)

Removed text from recent edits
During some of the recent edits of this page some of the previous text was commented out, I have tidied the page by removing those sections. In the hope of finding relevant reference material to support their later inclusion I have moved the sections to here:

On a railway climbing at a gradient of 1 in 40 (2.5%, or 25 m per km) a 360-degree spiral at 350 m radius will add 2200 m to the forward journey and 55 m to the vertical climb. Unless the topography has a suitably shaped hill, the spiral is likely to include a tunnel, increasing construction costs and creating problems if steam locomotives are employed. If a convenient side valley is available, then a horseshoe curve may be possible.
 * Calculations

The spiral needs to climb about 6 m in order to bridge itself. With steam locomotives and to a lesser extent with diesel locomotives, the gradient in any long tunnel(s) should be less than the ruling grade to avoid problems with fumes and dampness causing the driving wheels to slip.

An early spiral on the Brenner Railway is apparently called a winding.
 * Austria

Spiral south of Zudáñez on closed railway line starting at Taburoco
 * Bolivia

Transandine Railway connecting Chile and Argentina
 * Chile

Flåm Line: between Myrdal and Flåm – tunnels that spiral in and out of the mountainside. Rauma Line: near the Kylling Bridge
 * Norway

, Sredniy Petlevoy and Maly Petlevoy Tunnels (Major, Middle and Minor Loop Tunnels) – 3 tunnels on a single loop of North Caucasus Railway (44.2615°N, 39.24831°W)
 * Russia

At the Zand River crossing on the Bloemfontein to Kroonstad line the high-level bridge was destroyed by fighting in the second Boer War. Spiral tracks were constructed by military engineers to access a temporary bridge at river level.
 * South Africa

Farner, Tennessee - Marietta and North Georgia Railroad/Marietta and North Georgia Railway/Atlanta, Knoxville and Northern Railway/Louisville and Nashville Railroad/SCL-L&N Family Lines/Seaboard System Railroad/CSX Transportation - track wraps around a hill twice and crosses over itself on an 80 ft trestle. The "Golden Circle"/Homasville Loop/"Double Circle" Loop - Eureka, Utah – Tintic Range Railway/Rio Grande Western Railroad/Denver and Rio Grande Western - bypassed in 1940, abandoned, dismantled.
 * United States

oldish 13:53, 30 July 2016 (UTC)

Varzo spiral tunnel, Switzerland
The wiki article Simplon tunnel concludes with a section titled Spiral tunnel that states ''On the rail line north from Domodossola prior to the Simplon tunnels is the 2,968-metre (9,738 ft) "Varzo Spiral Tunnel", probably the longest spiral tunnel in the world. See the route diagram at the start of this subject.'' But I cannot find any mention of the Varzo spiral tunnel in the Spiral (railway) article. I can't add it because I'm no expert at geo-coordinates etc, so I'm just posting it here for investigation, leaving it to greater rail enthusiasts to check and add. Thanks. Pete Hobbs (talk) 15:54, 21 October 2016 (UTC)

This spiral is listed in the Italian section. oldish 15:25, 22 October 2016 (UTC) — Preceding unsigned comment added by Colinlangdon (talk • contribs)

Dhulghat spiral, India
This entry has been added as a 'former' spiral, yet the IRFCA website referenced shows the spiral still in use in 2015. Further information would be welcomed, has the metre gauge line been decommissioned? oldish 10:00, 24 August 2017 (UTC) — Preceding unsigned comment added by Colinlangdon (talk • contribs)

Norway - Flam
I've come across a good reference for the loop on the Flam line and so am reinstating it. The diagram in the reference definitely shows the line crossing itself. — Preceding unsigned comment added by Colinlangdon (talk • contribs) 15:05, 17 October 2017 (UTC)

Bolivia
The spiral on the extension of the Sucre - Tarabuco south of Zudáñez is there at: It is clearly visible on the satellite map and is indicated at openstreetrailway map.So the spiral was built. The question rather is if it ever was used. North of the spiral the line can be seen often making horseshoe curves but to the South there are almost no trans of the line. It was never finished, a destiny that also the other project to cross the Andean maintains within Bolivias met after 65 km building the line Eastward from La Paz. Maybe it was used during construction work, maybe not. Information about the line I scarce. UNDP mentions the lions Sucre - Tarabuco in its 1972 assessment of investments need in Bolivia stating the line needs to be closed due to lack of economic feasability. Whether it was used beyond Tarabuco I have not been able to find out, probably it was used as long as it reached any village. But I cannot find any traces of continued line after the spiral that reaches a village.

So what to do? Include a spiral that actually was built for a longer railway line but never really in use other than possible during its contruction? — Preceding unsigned comment added by Tord Björk (talk • contribs) 22:25, 19 June 2018 (UTC)

Peru
I have been unable to find, so far, a citation for the Peru spiral. It's on a very interesting line that has lots of switchbacks (zig-zags) and everything I have found so far focuses on them. However, the aerial photography clearly shows the spiral, as does OpenStreetMap.Nempnet (talk) 17:35, 16 September 2019 (UTC)

Eritrea
In a similar fashion to the Peru entry above. The map at openstreetmap and satellite photography both show this spiral, which immediately crosses itself back. Suitable citations are being sought and would be welcomed.Nempnet (talk) 11:12, 16 March 2020 (UTC)