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Comment by martinald | Hacker News Reader

I really don't think a train line with ~30tph in each direction is operating with no signals! I think you may be misunderstanding what 'signalisation' is? It's not just live display boards etc.

https://press.siemens.com/global/en/pressrelease/turkeys-mar...

Siemens says it has both CBTC and ERTMS. I imagine the interaction of the two is the problem, Elizabeth line in London was delayed by nearly 4 years because of the complexities of integrating multiple signalling systems (EL has 3 to contend with). It's actually a common problem of lines completed recently, as ERTMS wasn't considered robust enough to deal with "metro" style frequencies at the time, so CBTC was overlaid on top, but generally made every project that took this approach a bit of a disaster.

Now ERTMS is definitely mature enough for metro style frequencies new projects wouldn't use a proprietary CBTC system in conjunction with it.

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This is horrifying but true. We actually have an active court case against Siemens for corruption. Unfortunately, the court case was deemed as confidential because of national security and public order. No journalists are allowed in, protocols are kept secret.

There is wide reaching news articles about this topic, one example you can read it via google translate: https://www.cumhuriyet.com.tr/haber/marmarayin-neden-kapatil...

I believe Siemens is actively lying to cover up the corruption scandal. This will blow up hugely after the elections.

There is a press ban on the corruption scandal, all news articles have been ordered to be deleted, the article I read about the scandal has also been purged from the web, this is the tweet of the esteemed journalist who was tipped about the corruption scandal: https://twitter.com/baristerkoglu/status/1565395320296587265

This video shows signals everywhere: https://www.youtube.com/watch?v=vPE1yDddAiw

You can even see a train on the opposing line stopped at a signal before the platform.

You literally would have accidents daily if you had NO signals at all on such an intensive line. You cannot run more than one train on a line with no signals and not have accidents given the stopping distances of trains, you can't do it visually like a car. Perhaps you coudl get away with it on very long straight sections of track at lowish speed, but absolutely not a 30tph urban railway with curves, tunnels and frequent stations.

Maybe you mean there was no automatic train protection installed? That sounds very plausible to not be done right and disabled due to wanting the line open quickly or corruption.

Many train lines don't have ATP installed across the world. In the UK only a handful have lines have 'true' ATP which will stop the train if the train is speeding (right now it only stops it on most lines if it goes through a red signal, regardless of speed).

I believe the video shows a small part of the track and specially shot this way. In reality the signalization does not work reliably and is not available for the whole track.

I have never seen opposing trains running side by side, they only use rail tracks one-way and do not run trains side by side even in the same direction.

They do the coordination via sight and communicate through whatsapp and radio.

Ok I've totally lost you. Rail tracks are only used one way. You can see a train waiting at a signal.

There is absolutely 0 chance that you can do a 30tph service like you are describing. It simply isn't possible.

> There is wide reaching news articles about this topic, one example you can read it via google translate:

That article seems to be discussing how track works were being conducted without signal protection. Which is very different than no signals being installed.

The rest of your comment, regarding corruption scandal, seems totally possible.

> Now ERTMS is definitely mature enough for metro style frequencies

Is it quite? In Germany they're planning to resignal the core of the Stuttgart S-Bahn system with ETCS, but found that there is still a bit of development work to do in order to actually unlock additional capacity using ETCS, and so the whole project is treated a bit as a sort of pioneering pilot scheme for high capacity applications of ETCS.

In the UK ETCS is now in service on the Thameslink core, but AFAIK it has yet to see its design capacity of 24 tph being fully utilised – peeking through realtimetrains.co.uk, it looks like the current maximum peak service is 20 tph.

Well, it's mature enough that people are trying to do it now. Perhaps definitely is overkill :).

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