dehusmanHere's a thought, rather than rely on sketchy memories of things you probably didn't understand 40 years ago, why don't you produce some EVIDENCE that supports your opinion and establishes that you are correct. So far every single person that actually deals with ATC on a daily basis has told you you are mistaken.
Here's another thought: do a little research. According to Amtrak (in 2008) "ATC" was the term for "CSS + SCS" (the latter, explicitly 'speed control system', being implemented after 1952, nominally as one of the responses to the Spirit of St. Louis wreck in 1950.
Meanwhile, LIRR had a separate speed-control system, with its own distinct speed display (at least some implementation after its own high-profile wrecks in the early Fifties, specifically Kew Gardens). This was ASC, Rule 409, I think.
Bennett Levin and Hart of the NTSB both clearly indicate that a speed limiting function was implemented on CSS using a 'phantom device' that injects one of the restricting indications -- separated IIRC via the cab-signal/lsl 'drops' Zug referred to -- into a section of a formal CSS block. This is what would have been in use for the curve at Shore.
There is a useful primer on position-light CSS and some of its improvements here.
dehusmanThe train crews sees the restricting signal, but because they always get a restricting signal and they "know" the restricting signal is for the curve and they "know" they get a clear signal when they get out of the curve, they treat the restricting signal like just a speed restriction instead of a restricting signal. The go around the curve and run into the rear end of the train ahead.
That wouldn't be the fault of the signal system. That's the fault of the crew that is not following the signals and the rules.
Assuming gets your killed out here.
It's been fun. But it isn't much fun anymore. Signing off for now.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any
daveklepperIf someone can produce EVIDENCE, not opinion, that I am wrong in this memory, I will be glad to be corrected.
Here's a thought, rather than rely on sketchy memories of things you probably didn't understand 40 years ago, why don't you produce some EVIDENCE that supports your opinion and establishes that you are correct.
So far every single person that actually deals with ATC on a daily basis has told you you are mistaken. Since you are the one contradicting the professionals, YOU need to provide EVIDENCE that your recollection is correct. We have no responsibility to provide evidence of ghosts.
Dave H. Painted side goes up. My website : wnbranch.com
zugmannNo one is denying that. But for tight curves, (speeds below 50) it probably would be better than nothing (my opinion). Now with ACESES or PTC, it's a moot point.
In many ways using a signal intended for a specific purpose to have some other unrelated meaning can be more dangerous.
Here would be a "worst case" example. There is a 20 mph curve. The railroad sets up a permanent restricting signal approaching the curve. Every train going through the gets a restricting signal and all the crews know the restricting signal at that location is for the curve. When the rear of the train clears the curve the cab signals always pick up to a clear signal. Sounds good?
A train passes through the curve and goes in emergency just past the curve. A following train approaches the curve and gets a restricting signal because the block ahead is occupied. The train crews sees the restricting signal, but because they always get a restricting signal and they "know" the restricting signal is for the curve and they "know" they get a clear signal when they get out of the curve, they treat the restricting signal like just a speed restriction instead of a restricting signal. The go around the curve and run into the rear end of the train ahead.
Corrupting the signal indications is generally not a good plan.
Foxreader, were you ever in a PRR locomotive cab or front platform of an MU in regular service? My fuzzy memory has clarified, and I can state definitely that the PRR ATC system WOULD have prevented the derailment. If anybody remembers the block signal the controlled the entrance to that curve, or has photo, you will see that the clear block indication was not just a vertical line of lights, bur a vertical line of lights with a horizontal bar of lights immediately below. This was the lineside indication for a speed restriction. The cab signals had five or sometimes four lenses, For five, which was usual, top to bottom, vercial, vertical with horizontal bar, slanted, slanted with horizontal bar, and plane horizontal bar. I do not remember the exact configuration of four, but I think the slant with horizontal bar was replaced by ligjting the bottom two lenses.
This was true of lines from Pittsburgh east. I am not sure about wes of Pittsbugh or Norfolk and Western practice. These may have been different, at least as far as line-sides, and possibly different uses of the displays.` On the lineside, often when taking a divergent rout, the signal would display horizontal over vertical with horizontal bar, telling the engineer both that the diverging route woiuld be taken and 30 mph would be the maximum speed. But the cab signals gave speed indications only, no route indications.
If someone can produce EVIDENCE, not opinion, that I am wrong in this memory, I will be glad to be corrected.
So yes, PRR ATC would have prevented the accident if it had not been removed.
dehusmanI can't see why the PRR or AMTK would want to use the cab signals to ienforce speed restrictions on curves, its kind of a blunt force, crude way to do it.
No one is denying that. But for tight curves, (speeds below 50) it probably would be better than nothing (my opinion). Now with ACESES or PTC, it's a moot point.
I can't see why the PRR or AMTK would want to use the cab signals to ienforce speed restrictions on curves, its kind of a blunt force, crude way to do it. The cab signals only have the 4 speeds mentioned above. On a high speed route that would quickly bring and end to the "high speed" part. If the top speed on the route was 120 and you had a 90 mph curve, using the cab signals would force a 45 mph restriction. If you had a 75 mph the fastest you could go would be 45, even on the curve the 188 derailed on, a 50 mph curve you would still be forced to go slower than the safe speed. I don't see where any railroad would be happy with that solution.
Its certainly possible to do, I guess, but doing it would be horrible from a train operation perspective and I rode the PRR/CR/SEPTA for years commuting daily to college and I don't remember operation anything like that.
I have worked with territories that have ATC on them and none of them had that type of restriction and they were only 70 mph max freight lines.
The PRR cab signal system provided signal indication and speed enforcement for exceeding signaled speed. A CLEAR signal which is what #188 would have had would not have any speed limitation. The sytem had four states, Clear which which encoded the 100 Hz track current at 180 pulses/min, and left it to the engineer to operate the train at a safe speed; Medium Clear, which which encoded the 100 Hz current at 120 pulses/min, and would enfore a 45 mph speed; Approach which which encoded the 100 Hz current at 75 pulses/min and would enfoce a 30 mph speed; and Restricting which was the absence of either the 100 Hz current or any encoding, which would enforce a 20 mph speed.
PTC can enforce a much greater range of speeds than the older ATC. As can the Amtrak ACSE that is now in service.
I remember riding in the cab into Dayton OH from Indianapolis on a foggy night and all one could see was the fog bouncing the headlight back into our faces, but we knew there was no train ahead of us but if there had been an auto or pedestrian or cow on the track, we had NO clue. but we were On time and doing 90 mph and the engineer looked confident and he's telling me the worst thing he knew about was a buddy who hit a molasses truck. He also seemed to know when to whistle so I presumed he knew where he was. The obsevation of the crossing red lights in the fog as he ended his last long blast proved that he did.
The curve in question may or may not have had such a restriction enforced by ATC, but it is possible that it did.
You may be right about the PRR system. I may be remembering the premanent speed restrictions, such as the approach to Penn Sta., that had permanent yellows, yellow and red the only available signals (the position light equivalent,,obviously, including the cab signals.
One place I believe there was a speed restriction enforced by the ATC was both approaches to the drawbridge near the Portal. I do not know whether the signal was involveld there.
dehusmanExactly what I said, right from the horse's mouth (the PRR). The system is based on signal indication and applies a penalty application if the engineer does not comply with the signal indication. It has nothing to do with permanent speed restrictions.
Unless you add in a cut section that drops the cab signals.
From what I've heard - haven't had the chance to experieince it - where Amtrak has cut in their ACSES system, frieght trains with regular (PRR style) cabs/lsls get cab signal drops before every curve with a speed restriction. So even if the curve is good for 40, the cabs will drop to approach medium, and the LSL will enforce a 30mph speed.
zugmannPRR had speed control systems as well (skip ahead to 4:00 if in a hurry). Tied in with the cab signals,
Exactly what I said, right from the horse's mouth (the PRR). The system is based on signal indication and applies a penalty application if the engineer does not comply with the signal indication. It has nothing to do with permanent speed restrictions.
PRR had speed control systems as well (skip ahead to 4:00 if in a hurry). Tied in with the cab signals, so if you're running on clears they won't help for speed restrictions (that's what the ACESS and PTC stuff is taking care of now) - but even with the older cab signals -there' places where cab signals can be set to drop for speed restrictions/curves/etc. Just a matter of the magic and voodoo the C&S folks can do.
Frieght trains that operate on the NEC have to have LSL (locmotive speed limiters). They enforce speed restrictions in accordance to cab signals.
dehusman daveklepper My experience from ridinig MP54 front platforms is that that system did enforce at least important speed restrictions. ATC alerts on track occupancy/signal indication. It does not alert on either permanent or temporary speed restrictions. It would not have made any difference the 188 derailments since all reports I have seen indicate the train was operating on clear signals.
daveklepper My experience from ridinig MP54 front platforms is that that system did enforce at least important speed restrictions.
ATC alerts on track occupancy/signal indication. It does not alert on either permanent or temporary speed restrictions. It would not have made any difference the 188 derailments since all reports I have seen indicate the train was operating on clear signals.
It's not clear if the old PRR had such a system, The CNW did on some lines.[from Wiki] ATC systems in the United States are almost always integrated with existing continuous cab signalling systems. The ATC comes from electronics in the locomotive that implement some form of speed control based on the inputs of the cab signalling system. If the train speed exceeds the maximum speed allowed for that portion of track, an overspeed alarm sounds in the cab. If the engineer fails to reduce speed and/or make a brake application to reduce speed a penalty brake application is made automatically. Due to the more sensitive handling and control issues with North American freight trains, ATC is almost exclusively applied to passenger locomotives in both inter-city and commuter service with freight trains making use of cab signals without speed control.
C&NW, CA&E, MILW, CGW and IC fan
My impression, and of course a memory of front-platform rides of some 60-70 years ago can easily be in error, is that ATC on the PRR and LIRR was a bit more advanced than straight ATC and was used to enforce specific speed limits. It worked with the cab-signal system, of course, and the speed limits were reflected in the four or five displays cab-signal system, four displays plus possibly one available for blinking. If I am wrong, I will be happy to learn the corrections, and I am sure a reader here does have access to the hard data.
BigJim I peeked in to see how the "Amtrak Wreck in Philadelphia" was coming along and I find that you maroons have turned it into THIS! Where are the Moderators when you really need them??? "Oh, the shame of it all"
I peeked in to see how the "Amtrak Wreck in Philadelphia" was coming along and I find that you maroons have turned it into THIS!
Where are the Moderators when you really need them???
"Oh, the shame of it all"
Wave the flag for old ChicagoMaroon her color grandEver shall our team be victorsKnown throughout the land zumm rah rahWith the Grand Old Man to Lead usWithout a peer we'll stand.So Wave again that dear old bannerFor they're heroes, every man!
daveklepperMy experience from ridinig MP54 front platforms is that that system did enforce at least important speed restrictions.
daveklepperIn fact, it is my understanding that the PRR ATC system that had been removed in anticipation of the PTC installation would also have prevented the accident if it had not been removed!
Thereupon hangs a tale -- the rationale was that ATC to enforce speed limits was not in use at that point, in that direction, because speed limits on the immediately preceding section of track were low enough to preclude tipover derailment danger. I do not remember when that decision was taken, or indeed if PRR (or PC) had actually been using ATC for speed-enforcement penalty braking in that particular stretch of track (as opposed to block enforcement) and I'd like to know both.
I'm tempted to add that a satisfactorily prominent set of speed-limit signs might likely have prevented this particular accident at much lower cost, and with much more positive likelihood of safe resolution, than either a PTC or ATC penalty overspeed action. There's little as good as a big black 50 on a yellow background to snap you out of mistaken attention to radio traffic, or to remind you where you are in the dark...
Cheap and easy to implement, too, as Amtrak subsequently demonstrated.
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Back to Narig, I aggree PTC would have prevented the derialment. In fact, it is my understanding that the PRR ATC system that had been removed in anticipation of the PTC installation would also have prevented the accident if it had not been removed! My experience from ridinig MP54 front platforms is that that system did enforce at least important speed restrictions. The horn would blow and an immediate brake application would be expected or full service would be applied.
Obviously you just don't get it. Loretta Lynch told us today that the way to fight terrorism is with compassion, unity, and love. I guess if you don't agree you are a racist. It is easy to see why Dave is skeptical,or do you think we just need a little compassion, unity, and love for the kind of scum that commits these attacks?
It should not be a surprise, what with excrement rolling down hill, that people have lost confidence in the FBI and the NTSB. Our government has been so politicized that every agency is open to question.
Come on, you don't let somebody like that just skate away. Never in a million years.
Oh, the sky is falling, the sky is falling. Perhaps she is going to shoot the Donald.
The press is stirring the pot again.
How in the world would they not have the Orlando shooter's wife in custody while they investigated her complicity in the crime?
http://pamelageller.com/2016/06/mateen-wife-missing-loretta-lynch-admits-that-federal-authorities-have-lost-the-orlando-shooters-wife.html/
I have to stand by the comments I have made already. The ruling out of terrorism was done before the windshield was inspected for chemikcal tracds of a weapon projectile. I am not sayhing that there was a terrorist attack, but I am saying that to me the political climate has distorted the investigation. And the po sted comment from my friend comes from a person who lives in the Boston area, is of a different faith than mine, and not subject to the influences that Schlimm feels distorts my own perspective. Did not the political climate distort the Administration's announcements conlcerning the Bengazi event?
But I appreciate your noting the way Hamas and Hezbola, and in fact the PLO vote in Israeli elections. And this administrative detension etc. has not been applied exclusively to Arabs. It hasf also been applied in the extremely rare cases of Jewish violence against Arabs. And on occasion our courts have found ways to block the destruction of the homes of families of terrorists.
In defense of Israel I would point out that Israel is functioning democracy. It is at times messy. In addition Israel has many Arab members, both Moslem and Christian.
The worst problem I see with the Israeli democracy is the way Hezbollah and Hamas cast their votes in Israeli elections, either with rockets on settlements or suicide attacks. That scares people into agreeing with things a western democracy would wince at. Arrest without charge, indefinite detention, the army patrolling streets with shoot to kill orders, demolition of houses of families of dead suicide bombers, collective punishment of neighborhoods after attacks.
If you jump to conclusions you greatly increase the ability to just get it wrong. After something terrible you really need to take the time to study how to keep it from happening again.
You also need to be able to trust in the ability of those who study a problem to be able to judge the problem. All too frequently people accuse those who have done the work to understand what happens of "having an agenda" because one does not like the message. We, the United States taxpayers, pay the people in agencies and boards like the National Transportation Safety Board, and the Federal Bureau of Investigation to be experts on investigating issues. Just because you do not like what they tell you what the investigators found does not make the investigation invalid.
In this case NTSB has been stating that the best way to prevent future accidents like this wreck is PTC and equivalents(ACES). And NTSB has been persistent in this for a number of years. Thru operating crews missing signals and then wrecking equipment. Fatigue is another.
Not sure what else to say.
Questioning one's loyalty or one group's loyalty is not the same as genocide. Time is not always factual in either reporting on Israeli events or in quoting the entire statements of its politicians. Indeed, its review of the 6-Day War was deeply flawed with several statements contrary to fact. Lieberman did not recommend or suggest genocide as a solution to his putitive Arab disloyalty charge. Death penalty for TERRORISTS is not death penalty for a population. And any such legislation would be overruled by our courts, where justice IS THESAME FOR ALL ETHNIC GROUPS, and Lieberman cannot change that. But he did not even recommend population expulsion. Got it? Lots of people questioned Obama's loyalty to the USA and its Consitution in the Iran deal. And there are people who question my loyalty to the USA just because I chose to relocate to Jerusalem. None of this is genocide.
It is true the Bernie Sanders acused Netantyahu of genocide in the 2nd Gaze war. He later found out that he had been given an extremely inflated number for the Gaza casualties, and he then retracted his charge.
Lieberman was responding to one Israeli Arab Knesset member's statements in the Knesseet that Arab terror attacks had justification. That member's sympathies are clearly with the Palesitinian leadership; but, nevertheless, he retains his Knesset seat.
Schlimm, again as an eight-year old, I was almost killed by two anti-Semites banging my head against the concrete sidewalk at 88th Street and Central Park West, October or November 1940, but two much older boys from my school arrived in time to save my life. Anti-Semitism is still very rampant in this world, is espoused by numerous Arab countries plus Iran, and I ask you to stop identifying with those attackers, which to me you are doing. Martin Luther King said that an anti-Zionist is an anti-Semite. And do you know about the persecution of Christians and other minorities in the Muslim countries?
Before you post anything else on this particular side-topic, may I ask that you view and listen to Rabbi Hirsch's sermon on Orlando? Again, www.swfs.org. He really has the answers to the questions you pose for me, and possibly others as well.
zugmann If someone is that afraid, they better hide in their bubble at home. Excpet many accidents happen in the home - so they are boned either way. *shrugs*.
If someone is that afraid, they better hide in their bubble at home. Excpet many accidents happen in the home - so they are boned either way. *shrugs*.
Thanks to Chris / CopCarSS for my avatar.
You obfuscated, called me names, etc. but never dealt with the facts which I referenced about your Minister of Justice. And now the former foreign minister, the ultra-right Lieberman, is the new defense minister.
"Lieberman has continued to question the loyalty of Palestinian citizens of Israel, who make up 20% of the population, and has campaigned to make them sign a loyalty pledge or have their citizenship revoked. He is currently advocating for the death penalty for terrorists – although only for Palestinians who kill Israelis, not Israelis who kill Palestinians. " [Time, May 25]
Former Prime Minister Ehud Barak warns of "the seeds of fascism". Moshe Arens, who served as defense minister three times, sees it as a turning point in Israeli politics and expects it to cause a "political earthquake". [Reuters, May 23]
So perhaps they should be sued for slander too? I will not say any more on this [off, off-topic] but I do think most Americans have no idea of how extreme Israel has become. It's no longer the nation of Yitzhak Rabin, who was the cousin of my mentor.
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