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I take issue with the lack of positive train controls but moreso with the facts reported in the final paragraph. I was under the impression that locomotives ha

by kw71 11y ago

I take issue with the lack of positive train controls but moreso with the facts reported in the final paragraph. I was under the impression that locomotives had dead-man switches. The last paragraph implies that either the locomotive did not have a deadman switch or that maintaining it becomes so automatic for the operator that he mindlessly kept it up during his state of shock. In light of all the difficulty reported in installing the positive train controls which rely on trackside signalling equipment, I don't see why a GPS based train control system is not feasable, or at least one that gives instructions or sounds alarms in the cab. I'm only a layperson when it comes to locomotives, but my 2007 model Garmin GPS nav does tell me what speed limits are on nearly every road and warns me of upcoming turns.

maxerickson 11y ago
This article mentions the locomotive model and an alerter that beeps after a period of no input: http://www.businessinsider.com/the-amtrak-train-that-crashed-in-philadelphia-accelerated-the-minute-before-it-derailed-2015-5 http://www.businessinsider.com/the-amtrak-train-that-crashed... The Wikipedia page for the locomotive does not discuss the control system: http://en.wikipedia.org/wiki/Amtrak_Cities_Sprinter http://en.wikipedia.org/wiki/Amtrak_Cities_Sprinter Nor do a couple of the pamphlets listed in the sources there. Do you have a more concrete source for the deadman switch?
pm24601 11y ago
Its more than GPS. Much more than that: 1) which track is the train on? GPS off by a few meters 1 way or the other means a different track. 2) What are the switch settings ahead? 3) Is there a train stopped ahead? 4) Is there any obstruction ( i.e. rock fall )? 5) Are the crossing gates ahead properly functioning? 6) Are there vehicles across the crossing ahead? 7) What are the normal speed restrictions in place? 8) Are there maintenance workers ahead? 9) Are there temporary speed restrictions in place because of tracks needing repair? 10) What is the mass of the train? Heavier trains = greater stopping distance. 11) What is the track surface - leaves in the fall can create a biofilm that increases stopping distance. 12) What is the cargo - some cargo requires more gradual deceleration - bottles of wine anyone? 13) What about tunnels? 14) What about mountainous terrain with poor line of sight to GPS satellites? 15) What about signals that may interfere with a GPS fix? 16) What about going through cities with buildings and in trenches? Expanding on a few additional points: "Where is the train in front of this train"? a) Its not enough to know where the locomotive is: some freight trains can be 2 miles long. So if the train in front is 2 miles ahead but is a passenger train - no problem. A freight train? Big problem. b) Is the train ahead on a siding that the current train will not hit because the switch is thrown to transfer to another track> "What is the allowed speed?" a) Is the train going to take a speed restricted curve? b) Or continuing straight at a higher speed? c) How fast can the train decelerate - freight is slower than passenger trains. In a car its annoying -but having a train get confused and go into an emergency stop - that is something else. Can your Garmin do any of this?
- btown 11y ago
  All true points, but even though almost all of your points need to be solved to have fully automated speed control, they are not necessary if all you want to do is put an upper-bound on the speed of a train as it goes through a curve. Is there possibly a curve coming up? Slow the train down unless you have positive confirmation from fail-fast instrumentation that you're on a straightaway track and that all other trains nearby are accounted for. It doesn't prevent all accidents, but it prevents some, and it might have prevented this one. The article indicates that there are difficulties rolling out a full-service speed control system. Perhaps this tragedy will encourage them to roll out their bugfixes as they're implemented to whatever machines can accept them, rather than waiting for the entire release cycle to complete!
  - pm24601 11y ago
    Different environment here. A partial rollout can be deadly as well. Its worse than asking Boeing to do a "partial" rollout of aviation software. But its much more than just software - its hardware and different kinds of hardware as well. Its also multiple different railroading companies from all across the country, with 1000s of locomotives. For example, a UP locomotive may be attached to a cross-continental train in Oakland and end up on the NEC 8 days later. That UP locomotive would need to have the PTC hardware and software installed. Using foreign power happens all the time. When a train crosses from one railroad to another, at most a new crew comes on but the locomotive stays with the train. That new crew needs to know how to run the locomotive, there can't be wildly varying versions of PTC equipment onboard. Now throw in all the leasing companies that have equipment of varying ages and abilities to be retrofitted. And if life isn't complex enough, the NEC has 3 different electrification systems and a few short line railroads. Railroading has a heavy, hard-fought focus on safety. Before railroad companies got really serious about safety - railroading used to be quite dangerous. They are not going to just "rollout" releases. And to your statement about "not all of the issues need to be solved". Actually, yes they do because having trains just down or be slower than needed because of PTC is not reasonable either. Consider this, a well functioning railroad has an average car velocity of about 25 mph. A railroad that is snarled with locomotives badly positioned, crews going outlaw in the wrong place has a car velocity of 21 mph or so. Now you are going to throw in some half solution. Not. going. to. happen.

by kw71 11y ago

maxerickson 11y ago

This article mentions the locomotive model and an alerter that beeps after a period of no input: http://www.businessinsider.com/the-amtrak-train-that-crashed-in-philadelphia-accelerated-the-minute-before-it-derailed-2015-5 http://www.businessinsider.com/the-amtrak-train-that-crashed... The Wikipedia page for the locomotive does not discuss the control system: http://en.wikipedia.org/wiki/Amtrak_Cities_Sprinter http://en.wikipedia.org/wiki/Amtrak_Cities_Sprinter Nor do a couple of the pamphlets listed in the sources there. Do you have a more concrete source for the deadman switch?

pm24601 11y ago

Its more than GPS. Much more than that: 1) which track is the train on? GPS off by a few meters 1 way or the other means a different track. 2) What are the switch settings ahead? 3) Is there a train stopped ahead? 4) Is there any obstruction ( i.e. rock fall )? 5) Are the crossing gates ahead properly functioning? 6) Are there vehicles across the crossing ahead? 7) What are the normal speed restrictions in place? 8) Are there maintenance workers ahead? 9) Are there temporary speed restrictions in place because of tracks needing repair? 10) What is the mass of the train? Heavier trains = greater stopping distance. 11) What is the track surface - leaves in the fall can create a biofilm that increases stopping distance. 12) What is the cargo - some cargo requires more gradual deceleration - bottles of wine anyone? 13) What about tunnels? 14) What about mountainous terrain with poor line of sight to GPS satellites? 15) What about signals that may interfere with a GPS fix? 16) What about going through cities with buildings and in trenches? Expanding on a few additional points: "Where is the train in front of this train"? a) Its not enough to know where the locomotive is: some freight trains can be 2 miles long. So if the train in front is 2 miles ahead but is a passenger train - no problem. A freight train? Big problem. b) Is the train ahead on a siding that the current train will not hit because the switch is thrown to transfer to another track> "What is the allowed speed?" a) Is the train going to take a speed restricted curve? b) Or continuing straight at a higher speed? c) How fast can the train decelerate - freight is slower than passenger trains. In a car its annoying -but having a train get confused and go into an emergency stop - that is something else. Can your Garmin do any of this?

btown 11y ago
All true points, but even though almost all of your points need to be solved to have fully automated speed control, they are not necessary if all you want to do is put an upper-bound on the speed of a train as it goes through a curve. Is there possibly a curve coming up? Slow the train down unless you have positive confirmation from fail-fast instrumentation that you're on a straightaway track and that all other trains nearby are accounted for. It doesn't prevent all accidents, but it prevents some, and it might have prevented this one. The article indicates that there are difficulties rolling out a full-service speed control system. Perhaps this tragedy will encourage them to roll out their bugfixes as they're implemented to whatever machines can accept them, rather than waiting for the entire release cycle to complete!
- pm24601 11y ago
  Different environment here. A partial rollout can be deadly as well. Its worse than asking Boeing to do a "partial" rollout of aviation software. But its much more than just software - its hardware and different kinds of hardware as well. Its also multiple different railroading companies from all across the country, with 1000s of locomotives. For example, a UP locomotive may be attached to a cross-continental train in Oakland and end up on the NEC 8 days later. That UP locomotive would need to have the PTC hardware and software installed. Using foreign power happens all the time. When a train crosses from one railroad to another, at most a new crew comes on but the locomotive stays with the train. That new crew needs to know how to run the locomotive, there can't be wildly varying versions of PTC equipment onboard. Now throw in all the leasing companies that have equipment of varying ages and abilities to be retrofitted. And if life isn't complex enough, the NEC has 3 different electrification systems and a few short line railroads. Railroading has a heavy, hard-fought focus on safety. Before railroad companies got really serious about safety - railroading used to be quite dangerous. They are not going to just "rollout" releases. And to your statement about "not all of the issues need to be solved". Actually, yes they do because having trains just down or be slower than needed because of PTC is not reasonable either. Consider this, a well functioning railroad has an average car velocity of about 25 mph. A railroad that is snarled with locomotives badly positioned, crews going outlaw in the wrong place has a car velocity of 21 mph or so. Now you are going to throw in some half solution. Not. going. to. happen.