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by jplrssn1 days ago |
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upvoteby gpvos1 days ago|
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My thoughts as well. It appears that such signal failures happen so often that the controllers regularly let trains run through red under verbal authorization. I don't know the exact protocols, but I would expect a driver to ask for confirmation, as happened here, and then trust the control centre. However, there is clearly a huge systemic problem, with added complexity for the controllers, and there should at least be double checks in the control centre.
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upvoteby 17186274401 days ago|
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The person who controls whether the light shows red or green and gives verbal authorization is the same. It's both a tool, to transmit the same information.
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upvoteby pixl9717 hours ago|
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Same information, no.

A person saying you have a green light when you have a red light is not the same information at all. The probability that something has gone wrong and will lead to disaster is many many times higher.

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upvoteby 171862744015 hours ago|
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That's also true, but you should also be able to trust written movement authorities, otherwise why have them in the first place?
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upvoteby baobabKoodaa7 hours ago|
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The right move here would've been to accept the suggestion to drive the train, but not accept the suggestion to drive it at normal speed. The driver should have driven at 40km/h.
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upvoteby 171862744040 minutes ago|
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It's not a suggestion, it is an order and a movement authority. That would have been nice, but the drivers are not required to make such a decision. The moment you issue a movement authority, you must assume the train operates with the max speed and distance of it immediately, and that must be safe. Train drivers do not decide for the speed and trajectory a train is going to take. They are responsible for that their train drives safely inside the movement authorities given to them, they are not able and hence not responsible to ensure the safety of the network. They are more equivalent to a car mechanic, not to a car driver.
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upvoteby silon424 hours ago|
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+1 high speed should only be enabled by multiple redundant safety system being operational. Otherwise, it needs to operate at line of sight speeds.
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upvoteby 171862744038 minutes ago|
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"not high-speed" != "not line of sight" High speed is the speed when you can no longer safely drive by signals, not the speed when you are not able to safely observe the breaking distance. Trains are not supposed to operate under the latter (normally).
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upvoteby crote1 days ago|
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Trust but verify. You wouldn't drive your car into a lake just because your satnav tells you to, would you?

As we also know from the aviation industry, controllers are human and therefore will make mistakes. A controller shouldn't issue a wrong order, but a driver also shouldn't accept an order they aren't certain about, and there should be technical systems backing both sides of that up.

It doesn't "fall" on the driver, but it doesn't "fall" solely on the controller either. It's a systemic issue, and many pieces have to fail for a disaster to happen.

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upvoteby amunozo1 hours ago|
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A train is not a car. They accelerate and brake very slowly, you need kilometers to brake at high speed, it is impossible to check manually.
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upvoteby gus_massa18 hours ago|
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You can't verify, the rail has curves and other stuff that block sight.

Also stopping distance for trains is huge. This video for high speed trains says 5km (3mi) https://www.facebook.com/Renfe/videos/%EF%B8%8Fcu%C3%A1l-es-... That is probably at full speed, but IIUC the accident was at half speed so the distance should be like 1.2km (0.8mi).

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upvoteby baobabKoodaa7 hours ago|
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The driver tried to verify by asking a confirmatory question from the controller. So clearly there are in fact ways to verify, even if we can not achieve 100% certainty.

The driver also could have refused the order to drive at normal speed, and instead follow the protocol which caps speed to 40km/h in situations like these.

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upvoteby 17186274401 days ago|
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> As we also know from the aviation industry

The aviation industry operates like the railway industry ~1920 (somewhat by necessity).

> You wouldn't drive your car into a lake just because your satnav tells you to, would you?

You are assuming a train driver is equivalent to a car driver. He's not, the analog would be more a repairmen that you always take with you on journeys.

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