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N9JFE David SProject donor
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Message 1373647 - Posted: 30 May 2013, 17:50:09 UTC

I could have put this in the train thread, but it deserves its own.

http://www.nscorp.com/nscportal/nscorp/Media/News%20Releases/2013/ns_train_your_brain.html

Not that anyone here would be stupid enough to do that, of course.

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Message 1373657 - Posted: 30 May 2013, 17:58:54 UTC

The graphic billboards are part of Norfolk Southern's Train Your Brain public safety program, which warns motorists and pedestrians of the grave consequences of disregarding railroad signals and trespassing on railroad property.

Would have been better in the train thread.

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Message 1373665 - Posted: 30 May 2013, 18:08:46 UTC - in response to Message 1373657.

The graphic billboards are part of Norfolk Southern's Train Your Brain public safety program, which warns motorists and pedestrians of the grave consequences of disregarding railroad signals and trespassing on railroad property.

Would have been better in the train thread.



Not really, as it would have been ignored as pics of trains are better!

Too many road users are complacent in their thinking! Cars can be "DRIVEN", trains are not!

With a vehicle, you can steer it out of trouble, Trains are powered up/down & braked, no steering involved - the tracks steer the train.
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Message 1373670 - Posted: 30 May 2013, 18:18:01 UTC

In the Pacific Northwest Amtrak Trains Seattle to Portland have recently raised the speed limits to 79mph through residential neighborhoods all to shave something like 9 minutes off the run.

Needless to say folks are upset around here. With summer coming on there will be more deaths. They are knocking down about one a month now. More to come for sure. We still have to many crossing where the gates do not close the road and drivers can make it around the gates.
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Message 1373708 - Posted: 30 May 2013, 19:24:10 UTC

Railway tracks have the same signalling system that road users do, i.e. red, amber, and green. The railways call them signals, the roads call them traffic lights. Practically and mechanically, it is quicker to stop a car at 60 mph than it is to stop a train at the same speed, that is why traditionally the railways take precedence over road users.

However I think it is time that principle was changed. With modern railway disk brakes trains can stop a lot quicker than 50 years ago. Trains could be held or slowed at amber lights to allow road crossings ahead to close later rather than earlier. But of course it won't happen because the railways want to maintain their adherence to schedules to avoid fines for late running. Meanwhile motorists sit fuming at closed crossings, and on occasions take shortcuts.

The time was when all overground trains carried track clips, not any more. They could also be bought privately. Put one on, drive the car over, take one off, Job done :-) We all want train safety but trains are not god.

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Message 1373739 - Posted: 30 May 2013, 19:43:06 UTC - in response to Message 1373708.

However I think it is time that principle was changed. With modern railway disk brakes trains can stop a lot quicker than 50 years ago.


Really? You sure about that? You ever heard of Speed & Mass? No matter what braking system is used, it won't stop a train as quick as you think!
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Message 1373771 - Posted: 30 May 2013, 20:12:35 UTC - in response to Message 1373657.

The graphic billboards are part of Norfolk Southern's Train Your Brain public safety program, which warns motorists and pedestrians of the grave consequences of disregarding railroad signals and trespassing on railroad property.

Would have been better in the train thread.


I agree with Sirius B, this would have been ignored in favor of pictures.
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Message 1373773 - Posted: 30 May 2013, 20:13:39 UTC - in response to Message 1373739.

However I think it is time that principle was changed. With modern railway disk brakes trains can stop a lot quicker than 50 years ago.


Really? You sure about that? You ever heard of Speed & Mass? No matter what braking system is used, it won't stop a train as quick as you think!

Yep. Probably at least a mile.
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Message 1373780 - Posted: 30 May 2013, 20:23:50 UTC
Last modified: 30 May 2013, 20:28:59 UTC

Railway tracks have the same signalling system that road users do, i.e. red, amber, and green. The railways call them signals, the roads call them traffic lights.


The red green and amber is not universal, as I am sure David can confirm, different railroads in the US use different systems.

In the UK we use the "block system" trains are separated by an electrically isolated block of track. Also in the UK green means you can proceed at maximum line speed, a green signal would only change to red in an extreme emergency. Single amber means the next signal is red proceed at half line speed. In a 4 aspect system a double amber means the next signal is amber be prepared to slow at next signal and of course red means stop. The amber, and red signals can change as the train approaches.

A fully laden UK freight train at 40 MPH can take up to a half mile to stop, so I am afraid the only answer is to phase out all vehicle crossings.

If you want the full picture go here http://en.wikipedia.org/wiki/UK_railway_signalling
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Message 1373783 - Posted: 30 May 2013, 20:32:03 UTC - in response to Message 1373780.

Correct. In the UK at least, Amber is not a stand-alone signal but a repeater of the signal ahead.
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Message 1373787 - Posted: 30 May 2013, 20:34:45 UTC - in response to Message 1373739.

However I think it is time that principle was changed. With modern railway disk brakes trains can stop a lot quicker than 50 years ago.


Really? You sure about that? You ever heard of Speed & Mass? No matter what braking system is used, it won't stop a train as quick as you think!


Chris is correct - with modern braking systems the stopping distance for trains has been reduced quite considerably. We did one test where we stopped a train from 160kph to zero, then accelerated back to 160kph in less distance than an A4 with 12 on took to stop from the same speed. I can say it was "not comfortable" for those in the train, but it was spectacular! (Oh, and we didn't slide at all during the stop)
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Message 1373793 - Posted: 30 May 2013, 20:41:29 UTC - in response to Message 1373787.

Interesting & what was the stopping distance on that test?
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Message 1373813 - Posted: 30 May 2013, 21:06:50 UTC

Something in the region of 900m - I've not got my notes at home (not bad for a 500 tonne plus train)
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Message 1373819 - Posted: 30 May 2013, 21:14:31 UTC - in response to Message 1373787.

However I think it is time that principle was changed. With modern railway disk brakes trains can stop a lot quicker than 50 years ago.


Really? You sure about that? You ever heard of Speed & Mass? No matter what braking system is used, it won't stop a train as quick as you think!


Chris is correct - with modern braking systems the stopping distance for trains has been reduced quite considerably. We did one test where we stopped a train from 160kph to zero, then accelerated back to 160kph in less distance than an A4 with 12 on took to stop from the same speed. I can say it was "not comfortable" for those in the train, but it was spectacular! (Oh, and we didn't slide at all during the stop)

I think that's for a passenger train, from what I've read, here in the US freight trains can be about 15,000 tons, depending on what the contents of the train are of course, as mentioned Here.

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Message 1373824 - Posted: 30 May 2013, 21:22:07 UTC - in response to Message 1373813.

Something in the region of 900m - I've not got my notes at home (not bad for a 500 tonne plus train)


That's not bad at all. Still wouldn't like to be in the way :)
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Message 1373920 - Posted: 31 May 2013, 0:40:23 UTC - in response to Message 1373813.
Last modified: 31 May 2013, 0:40:58 UTC

Something in the region of 900m - I've not got my notes at home (not bad for a 500 tonne plus train)

Okay, that's about half a mile, but as Vic pointed out, freight trains in the US can be two to three times that heavy. Even with 3 or 4 engines applying braking power, 1/2(mv^2) still applies. Trains CANNOT stop as fast as cars.
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Message 1373937 - Posted: 31 May 2013, 2:17:38 UTC - in response to Message 1373708.

However I think it is time that principle was changed. With modern railway disk brakes trains can stop a lot quicker than 50 years ago.

The coefficient of friction of a steel wheel on a steel rail hasn't changed. But the coefficient of friction of a modern tyre on a road has.

As to "disc" brakes, perhaps on electric light rail passenger service, but they don't exist on freight. In an emergency stop the brakes can cease wheel rotation. Railroads don't like that as it flat spots their wheels and causes excessive wear on the rails. The train will still slide a mile.

Finally the amount of energy needed to get a freight train up to speed is a lot more than you think. Shame to waste it to stop for a car to cross the tracks.

For some idea of the forces involved http://en.wikipedia.org/wiki/2008_Chatsworth_train_collision

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Message 1373947 - Posted: 31 May 2013, 2:50:15 UTC

Around here a busy rail crossing sees dozens or hundreds of cars per hour, and maybe 20 or 30 trains a day. And most of those are very long and heavy freights (thousands or tens of thousands of tons). Stopping a train for a car would be very impractical, if not impossible.

As Bernie said, the long term solution is to get rid of level crossings (as we call them hereabouts). All that takes is time and money.

A short term solution used hereabouts is to limit train travel to off-peak road traffic hours.
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Message 1373966 - Posted: 31 May 2013, 3:53:16 UTC - in response to Message 1373937.

Leaving aside the matter of friction, after all, the thread is about train safety.

The link you provided is highly interesting from a safety POV.

It was proven that the engineer of the Metrolink train passed a signal at red because he was "texting".......

...Was he also deaf? On our trains (mainline as no need for audible alarms on the Underground as the tripcock enters play if one passes a red signal), an audible alarm is given if a train passes a red signal - as Metrolink didn't have their whole system on ATS, surely audible alarms were in place?

If not? Why Not? Is it possible that your favourite term applies here? You know, that shareholder thingamejob where profits come 1st!
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Message 1373972 - Posted: 31 May 2013, 4:05:57 UTC - in response to Message 1373947.

Around here a busy rail crossing sees dozens or hundreds of cars per hour, and maybe 20 or 30 trains a day. And most of those are very long and heavy freights (thousands or tens of thousands of tons). Stopping a train for a car would be very impractical, if not impossible.

As Bernie said, the long term solution is to get rid of level crossings (as we call them hereabouts). All that takes is time and money.

A short term solution used hereabouts is to limit train travel to off-peak road traffic hours.

Down in Alhambra CA and San Gabriel CA, the trains are down in a trench, better than at ground level like when I was growing up.
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