Derailment closes world's longest Rail Tunnel in Switzerland until 2024

[slasher-fun]

By the way, for the purposes of evacuating people from stranded trains, I understand there is a walkway alongside the tracks, so its not as if the trains fit tightly with only inches to spare.

Yes, better view of the size of the tunnel here: File:Einbau der Bahntechnik im Gotthard-Basistunnel (7029412313).jpg - Wikimedia Commons

Looking at the video above posted by @slasher-fun, I wonder if in Europe they have any equivalent of Blue Flag protection to prevent movement of the train while someone is between the cars.

Yes, the exact system is different in each country, but basically either or both:
- a sign/flag is attached at both ends of the train
- the train driver has to give the "main key" (not sure about its name in English) of the locomotive to the person working between the cars

 

[cirdan]

Looking at the video above posted by @slasher-fun, I wonder if in Europe they have any equivalent of Blue Flag protection to prevent movement of the train while someone is between the cars.

Getting back to the tunnel itself, I understand that some passenger trains are using it particularly on weekends when there is less freight traffic. Mostly double deck trains which cannot run via the old route and also provide more capacity.

I won't swear that I am 100% certain but i am pretty sure that double deck trains can, and have sometimes, run on the old route.

 

[George Harris]

There you go:
- before: https://www.railjournal.com/wp-content/uploads/2023/08/1497015651-tor-jpg.jpg
- after: https://www.lfm.ch/wp-content/uploa...degats-dans-le-tunnel-du-gothard-archives.jpg
The door is not visible on the picture in your article because there's the train in front of it

Gotcha. See now that the door(s) was(were) across the tunnel section. Was looking for evidence of a door down the middle so that the tunnels would be separated unless the crossover was to be used.

Coupling issues. Answer noted. It is still a very archaic system that most of the rest of the world has discarded in favor of the AAR style system or something similar.

Train lengths:

No the main reasons are:
- the signalling systems, designed for trains up to 750 meters long in most places
- the sidings, also designed for trains up to 750 meters long in most places

Noted. Guess there has not been the push toward more economic freight operation that has resulted in many siding extensions in North America and other places to permit longer trains, which by the way does improve things operationally as there are significantly fewer freight trains needed to move the same volume of freight.

Don't worry, the Swiss are experts when it comes to trains, they know what they're doing
Trains can reach 250 km/h there, so train resistance is definitely not an issue with this tunnel section.

When it comes to tunnel aerodynamics, it is not always necessarily efficient to push the air aside which would mean compressing it, which absorbs a lot of energy and generates additional heat in a location that is difficult to cool. Pushing a column ahead of the train may be more efficient, depending on how long that column is. I am sure this has been studied at length and that the tunnel designers took all these considerations into account.

Not arguing that you cannot run 250 kph or higher in a tight tunnel, just that it requires more energy to do so.
To cirdan: No, pushing a long column of air is not more efficient. The tighter the clearance, the higher the proportion of air that is pushed instead of passed. This increases train resistance. There is less compression of both the bypassed air and the pushed air when the area between train and structure is larger. There should be available technical literature that could put some numbers and proportions on this subject. Have been involved in this sort of discussion in past years but there were others that ran the numbers and made the ultimate decisions.

 

[slasher-fun]

Coupling issues. Answer noted. It is still a very archaic system that most of the rest of the world has discarded in favor of the AAR style system or something similar.

Yup, there are so pushes from some manufacturers, but the main issue is the high cost of having to install a new system on not very valuable wagons, vs pretty low benefits.
Technology allowing for "Digital Coupling" might be the tip needed for things to change though. https://rail-research.europa.eu/wp-content/uploads/2021/04/DAC-Factsheet_EN.pdf

Noted. Guess there has not been the push toward more economic freight operation that has resulted in many siding extensions in North America and other places to permit longer trains, which by the way does improve things operationally as there are significantly fewer freight trains needed to move the same volume of freight.

Fewer freight trains needed... but huge costs (longer sidings are one thing, but longer trains also means heavier trains, so the whole tracks would have to be streghtened, the power stations improved / multiplied, etc), and capacity for fewer trains (because of the longer distance between signals).
Unlike in America, train is mainly used for passenger traffic in Europe: on average, 80% of train.km are passenger trains, the longest of them not exceeding 400 meters length (vs 750 m for freight), and therefore would not benefit of this possibility for longer trains, whereas rail congestion is already definitely an issue in the dense parts of Europe ("rail punctuality in Germany" for example ).

 

[jis]

Interesting! In India passenger trains can routinely be 750m long! Freights are a km long, and when they are running on the dedicated freight corridors they usually couple up two of them together since the passing sidings are that long on the DFCs. When they come off they just uncouple them and let them go on their merry way on the classic network.

 

[slasher-fun]

Can they? I would passengers trains in India were up to 24 cars long, which is about 600 m long (and that's already a very long passenger train, as it requires... 600 m long platforms!).

 

[jis]

Can they? I would passengers trains in India were up to 24 cars long, which is about 600 m long (and that's already a very long passenger train, as it requires... 600 m long platforms!).

Well the longest are 26-27 LHB cars. So they are not quite at 750, but the current plans appear to be to have major stations upgraded to 700-750m platforms. There are already some stations with 1km long platforms. The demand pressure is so high that this sort of thing is likely to happen. For now the articulated fixed consist sets are 16 cars, but they are not the majors carriers of the masses, mainly because they are air conditioned. It is actually odd since the non fixed consist fully air-conditioned trains are 22-24 cars like the longest Rajdhanis. Masses don't do air-conditioned. They are too expensive. They do classic trains which are not length limited by fixed consist lengths.

But this is getting far afield from the subject of this thread.

 

[cirdan]

Fewer freight trains needed... but huge costs (longer sidings are one thing, but longer trains also means heavier trains, so the whole tracks would have to be streghtened, the power stations improved / multiplied, etc), and capacity for fewer trains (because of the longer distance between signals).
Unlike in America, train is mainly used for passenger traffic in Europe: on average, 80% of train.km are passenger trains, the longest of them not exceeding 400 meters length (vs 750 m for freight), and therefore would not benefit of this possibility for longer trains, whereas rail congestion is already definitely an issue in the dense parts of Europe ("rail punctuality in Germany" for example ).

Also, longer trains would take longer to move into or out of sidings. As you say the network carries predominantly passenger trains and many aspects are designed for passenger trains. Basically passenger operations get the first pick of the best slots when the schedule is designed and freight trains need to be worked around this rather than vice versa. This means freight trains need to be moved into and out of sidings to allow passenger trains to pass. Long trains will need more time to do this and hence it is more difficult to find suitable slots for them.

Concerning train lengths, in some places the 750m are more an upper boundary they are still striving towards. For example on some secondary lines in Spain and elsewhere sidings are considerably shorter than this and they are still trying to find ways (and funds) of lengthening them (most money tends to go into passenger stuff and freight is often expected to make do with the infrastructure that is provided). This means such routes either don't get much freight at all, or trains need to be switched and split up to be able to use them.

That said, in most places (excepting a few pinch points) it is not train capacity that is the main barrier to growth in freight by rail but other considerations including intense competition by trucks (which do not pay the full costs of the highways infrastructure) and also political issues with support for freight by rail often being a lot of talk but little action. International borders are often also still causes of delays as different railroads don't talk to one another or cooperate as well as they could. A lot of freight runs at night when there are no passenger trains to get in the way, but unfortunately this is also prime time for track maintenance and freight trains are often delayed or cancelled. The state-owned incumbent railroads often create barriers making it more difficult than necessary for private railroad companies to gain access to the infrastructure, and thus limit competition and innovation, while displaying old-fashioned and often unwelcoming attitudes towards customers. Time and time again we hear horror stories of customers who attempted to shift their business to rail for environmental reasons, only to get a very raw deal from the railroad.

 

[joelkfla]

Also, longer trains would take longer to move into or out of sidings. As you say the network carries predominantly passenger trains and many aspects are designed for passenger trains. Basically passenger operations get the first pick of the best slots when the schedule is designed and freight trains need to be worked around this rather than vice versa. This means freight trains need to be moved into and out of sidings to allow passenger trains to pass. Long trains will need more time to do this and hence it is more difficult to find suitable slots for them.

Concerning train lengths, in some places the 750m are more an upper boundary they are still striving towards. For example on some secondary lines in Spain and elsewhere sidings are considerably shorter than this and they are still trying to find ways (and funds) of lengthening them (most money tends to go into passenger stuff and freight is often expected to make do with the infrastructure that is provided). This means such routes either don't get much freight at all, or trains need to be switched and split up to be able to use them.

That said, in most places (excepting a few pinch points) it is not train capacity that is the main barrier to growth in freight by rail but other considerations including intense competition by trucks (which do not pay the full costs of the highways infrastructure) and also political issues with support for freight by rail often being a lot of talk but little action. International borders are often also still causes of delays as different railroads don't talk to one another or cooperate as well as they could. A lot of freight runs at night when there are no passenger trains to get in the way, but unfortunately this is also prime time for track maintenance and freight trains are often delayed or cancelled. The state-owned incumbent railroads often create barriers making it more difficult than necessary for private railroad companies to gain access to the infrastructure, and thus limit competition and innovation, while displaying old-fashioned and often unwelcoming attitudes towards customers. Time and time again we hear horror stories of customers who attempted to shift their business to rail for environmental reasons, only to get a very raw deal from the railroad.

Oh, would that American freights were limited to trains that could fit into their sidings.