• The stopping guidelines have officially been dumbed down

  • Discussion related to DC area passenger rail services from Northern Virginia to Baltimore, MD. Includes Light Rail and Baltimore Subway.
Discussion related to DC area passenger rail services from Northern Virginia to Baltimore, MD. Includes Light Rail and Baltimore Subway.

Moderators: mtuandrew, therock, Robert Paniagua

  by litz
 
MARTA seems to hit their stop points with good regularity ... there are no markings on the floor, but regular riders "know" the right spots, and there's wear marks on the floor.

They won't hit the mark within 2 inches like the Japanese can, but it'll usually be within a foot.

- litz
  by jamesinclair
 
arrow wrote:
krtaylor wrote:I thought that WMATA actually was set up to have the automatic computer controls stop the trains at the correct locations, which would solve this problem. Why do they have clearly incompetent human beings doing this?

When I was in Japan, not only did the trains there stop at logical places on the platform, but they had metal circles inset in the floor to indicate exactly where the doors would be when the trains stopped. People would form a neat queue at that spot... and sure enough, the trains always stopped in precisely the right spot, within a couple inches.

No excuse whatsoever.
Because they have incompetent humans maintaining the equipment and incompetent humans making decisions.

Out of the 3 systems that run the trains, they disable the 2 that had nothing to do with the crash. They must think the public is really stupid, but I think the public does actually feel better hearing that they've "solved the problem" by running trains in manual mode. There's really no excuse for that either.
The US is probably the only country in the world where "running in manual" makes people feel safer than "computer operated"
  by arrow
 
jamesinclair wrote:
arrow wrote:
Because they have incompetent humans maintaining the equipment and incompetent humans making decisions.

Out of the 3 systems that run the trains, they disable the 2 that had nothing to do with the crash. They must think the public is really stupid, but I think the public does actually feel better hearing that they've "solved the problem" by running trains in manual mode. There's really no excuse for that either.
The US is probably the only country in the world where "running in manual" makes people feel safer than "computer operated"
You may be right. I think the system they'd been using was a good one. Let the computer run the trains and have the operator there to give the illusion that the human is still in control if it makes people feel better.
  by Sand Box John
 
"arrow"

Out of the 3 systems that run the trains, they disable the 2 that had nothing to do with the crash. They must think the public is really stupid, but I think the public does actually feel better hearing that they've "solved the problem" by running trains in manual mode. There's really no excuse for that either.


The only systems that been disabled is the system that automatically opens the doors when operating in automatic mode. That was done before the crash.
  by jamesinclair
 
arrow wrote:
jamesinclair wrote:
arrow wrote:
Because they have incompetent humans maintaining the equipment and incompetent humans making decisions.

Out of the 3 systems that run the trains, they disable the 2 that had nothing to do with the crash. They must think the public is really stupid, but I think the public does actually feel better hearing that they've "solved the problem" by running trains in manual mode. There's really no excuse for that either.
The US is probably the only country in the world where "running in manual" makes people feel safer than "computer operated"
You may be right. I think the system they'd been using was a good one. Let the computer run the trains and have the operator there to give the illusion that the human is still in control if it makes people feel better.
It would be cheaper to just have an inflatable dummy, like in the airplane movie
  by arrow
 
Sand Box John wrote:"arrow"

Out of the 3 systems that run the trains, they disable the 2 that had nothing to do with the crash. They must think the public is really stupid, but I think the public does actually feel better hearing that they've "solved the problem" by running trains in manual mode. There's really no excuse for that either.


The only systems that been disabled is the system that automatically opens the doors when operating in automatic mode. That was done before the crash.
I was referring to the fact that they no longer are using the automatic control systems, even though automatic/manual had nothing to do with the crash.
  by arrow
 
jamesinclair wrote: It would be cheaper to just have an inflatable dummy, like in the airplane movie
:-D :-D I'll keep my comments to myself!
Last edited by arrow on Sat Oct 03, 2009 8:17 pm, edited 1 time in total.
  by Sand Box John
 
"arrow"
I was referring to the fact that they no longer are using the automatic control systems, even though automatic/manual had nothing to do with the crash.


If you are referring to the train board automatic control systems, then yes you are correct. However, the signaling system fail to detect the presents of a train in an occupied track circuit. The signaling system transmitted cab signals (speed commands) to the following track circuit as if the occupied track circuit was not occupied. Speed commands are interracial to the safe operation of trains in both automatic and manual mode.
  by arrow
 
Sand Box John wrote:"arrow"
I was referring to the fact that they no longer are using the automatic control systems, even though automatic/manual had nothing to do with the crash.


If you are referring to the train board automatic control systems, then yes you are correct. However, the signaling system fail to detect the presents of a train in an occupied track circuit. The signaling system transmitted cab signals (speed commands) to the following track circuit as if the occupied track circuit was not occupied. Speed commands are interracial to the safe operation of trains in both automatic and manual mode.
I know. That's my point exactly. The ATP system you describe is still in operation since it's a necessity. That is the system that failed. The remainder of the automated system did not fail and did not contribute in any way towards the crash, yet they disable that so that the public gets some kind of sense of security I guess. It just doesn't make sense to me.
  by justalurker66
 
The NTSB and WMATA have taken steps that may have prevented the accident. Running in manual isn't one of those steps. While the fault at the root is the signaling system losing the train, running the system in automatic tends to turn the operators into passengers with little to do but go along for the ride. While they are expected to keep the train in safe operation, the tedium of thousands of safe trips and safe station stops with no operator input required can put the best operator to sleep. Yes, they are supposed to watch the rails and signals but why bother if the train is watching the rails and signals for them and the work culture is that the automatic train control is smarter than the humans. Unfortunately an operator who was doing her job with her cellphone put away out of reach and who was watching out enough to attempt an emergency stop was killed in this accident. It was the WMATA system itself that was asleep on the job. Repeating the errors of the past where too much trust was put in the computers.

While running in manual would not have prevented the accident it is giving operators more to do and leading to more attentive operation of the train. Perhaps when something is wrong in the future operators will notice it before the accident. And WMATA management will wake up and fix it. It does no harm to have more attentive operators.
  by krtaylor
 
Why, then, are systems elsewhere in the world able to run perfectly safely with automatic systems, whereas we know that human-operated equipment will always be prone to error and accident? Shouldn't we be studying what's done right elsewhere rather than just giving up and accepting the inherent human accident rate?
  by Sand Box John
 
"krtaylor"
Why, then, are systems elsewhere in the world able to run perfectly safely with automatic systems, whereas we know that human-operated equipment will always be prone to error and accident? Shouldn't we be studying what's done right elsewhere rather than just giving up and accepting the inherent human accident rate?


This is easy to answer.
1: Most fully automated systems elsewhere in the world today use technologies and hardware that are generations newer and are mostly technologically different then WMATA.
2: WMATA uses 40 year old hardware that is based on technology that was developed more then 80 years ago. The 40 year old hardware, has worked pretty damm good over the years. It has been proven to be robust and reliable. The issue that needs to be addressed is proper maintenance of said hardware, not studying how to reinvent the wheel.

It is important to note that youngest parts of the railroad use hardware that are generations newer then the oldest hardware found on the older parts of the railroad. The newer hardware uses digital technology to emulate some of the functions of the older analogue technology.
  by arrow
 
krtaylor wrote:Why, then, are systems elsewhere in the world able to run perfectly safely with automatic systems, whereas we know that human-operated equipment will always be prone to error and accident? Shouldn't we be studying what's done right elsewhere rather than just giving up and accepting the inherent human accident rate?
I completely agree with you. I also disagree with justalurker66. Operators are not necessary for the safe operation of the system. Obviously we saw that the operator couldn't stop the crash anyway.
  by Head-end View
 
Arrow I disagree. the reason the human operator was not able to stop the train in time was because the curve prevented her from seeing the other train until it was too close to stop. Had the incident occurred on a straight stretch, she would have seen it sooner, and might have been able to stop in time. We still need a human operator on a train to take over in an emergency.
  by Sand Box John
 
"Head-end View"
Arrow I disagree. the reason the human operator was not able to stop the train in time was because the curve prevented her from seeing the other train until it was too close to stop. Had the incident occurred on a straight stretch, she would have seen it sooner, and might have been able to stop in time. We still need a human operator on a train to take over in an emergency.


You are contradicting youself. First you say she saw the stopped train to late to stop, then you say we need a human operator to take over in an emergency.

The only way your schema can work is to restrict speeds to allow the stopping of train based on sight distances.

Not a very efficient use of the infrastructure, considering that some of the sight distances in the underground sections are as little as 300'.