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Flashing Signals

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Flashing Signals
Posted by Soo2610 on Tuesday, May 15, 2001 11:47 PM
There is a mainline signal on the WC just south of I-43 in Mukwonago, Wisc. I have seen this signal displaying solid green, yellow, red and on occasion flashing yellow or red. What exactly does the flashing signal indicate? Have also seen a flashing red on the entrance to the CP yard in Besenville. I Assume this is the same type of signal.
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Posted by Anonymous on Wednesday, May 16, 2001 2:03 AM
Not sure about WC but on the Santa Fe flashing yellow is Approach Medium not to exceed 40mph,.

solid yellow Approach, prepared to stop at next signal, trains exceeding 40 mph immediately reduce to that speed.

Flashing red or lunar (white) Restricting, proceed at restricted speed.

gwl
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Posted by wabash1 on Wednesday, May 16, 2001 8:51 AM
each railroad it seems has differant meanings for the same thing. a flahing yellow on the ns means approach resticted. proceed approaching next signal at restricted speed not exceeding 15 mph train or engine exceeding medium speed must at once reduce to that speed.( medium speed being 30 mph). the flashing red if not involed with a detector i dont know what it mean on main line movement.
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Posted by Soo2610 on Wednesday, May 16, 2001 9:02 PM
Thanks for the response guys. My guess was right on the flashing yellow. I have actually seen trains go thru the flashing red in the CP Besenville yard. Don't know about the WC main which I believe is under CTC control at that point. J, Do you ever sleep? AS an NS engineer I assume you are on call 24 hours and have seen your replies at all hours of the day.
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Posted by Anonymous on Wednesday, May 16, 2001 9:31 PM
Seems that no one has mentioned flashing green... I've seen that in northern VA on the CSX mainline, the former RF&P.
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Posted by wabash1 on Thursday, May 17, 2001 12:52 AM
well like now i just got in and im going to bed soon. just wanted to see what everyone was talking about. and yes its at all times of the day or night that i work my favorite time to get out on the road and run is 2am.
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Posted by Soo2610 on Thursday, May 17, 2001 11:44 PM
Man, I thought this was going to be a relatively simple and straightforward question. About the only thing that hasn't been thrown into the mix is a flashing white. I didn't think the flashing red would be such a stumper and I've seen it on more than one occasion and on different lines.
2AM is definitely NOT my favorite time to be up and about. This old gray stallion can not take those hours anymore. The house would have to be burning down or I would have to be leaving on a deer hunting trip and even then I wouldn't be very bright eyed and bushy tailed. Anyway, I don't think I have ever seen the flashing green that Tom mentions.
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Posted by Saxman on Saturday, May 19, 2001 1:06 PM
Flashing signals convey different indications depending on the signal system used by the individual railroad such as route signaling or speed signaling. Route signaling telling which route the train will take and speed signaling govering speed at a particular location such as turnouts.

On the former Grand Trunk Western, a red over flashing green over red on a high mast signal or a flashing green over red on a dwarf signal indicates "Limited Clear." Proceed not to exceed 45 MPH within interlocking limits or through turnouts. A flashing yellow in place of the flashing green would indicate "Limited Approach." Proceed not to exceed 45 MPH within interlocking limits or through turnouts; then proceed prepared to stop at next signal. The signal previous to either of these, would tell the engineer to approach the next signal at Limited Speed.

A flashing yellow either by itself on a high mast signal or with one or two red aspects below it it, indicates "Advance Approach." Proceed prepared to stop at second signal. If the flashing yellow is below one or two red aspects on a high mast signal, below a red aspect or by itself on a dwarf signal, the indication would be "Slow Approach." Proceed not to exceed 15 MPH within interlocking limits or through turnouts; then proceed prepared to stop at next signal.

On the former Grand Trunk Western, the flashing red is not used. It is used on the former IC. If the signal indication is Red over Flashing Red it would indicate "Restricting." Proceed at restricted speed.

As can be seen by the various reponses, there is no one answer to what a flashing green, yellow or red is indicating.



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Posted by Soo2610 on Saturday, May 19, 2001 6:31 PM
Terry, Thanks, I think. This is beginning to get complicated. The signals I saw were stand alone single signals not over or under another color and not by a siding. This is single track ctc mainline at this point. As near as I can tell there is no detect at this location.
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Posted by Saxman on Monday, May 21, 2001 4:44 PM
Len,

The flashing yellow signal on the Wisconsin Central is an Advance Approach. Proceed approaching next signal not to exceed 40 MPH. The flashing red signal is a Restricting. Proceed at Restricted Speed. According to signal charts I have for the Wisconson Central, both of these indications can be displayed as a single aspect high mast signal.

Hope this answers your question.

Terry
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Posted by Soo2610 on Monday, May 21, 2001 4:54 PM
THANKS!!
It does!
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Posted by Justicar on Saturday, May 26, 2001 5:36 PM
Len,

As a sidenote and to offer some historical perspective on flashing signals, they are lazy-man's signalling. I'm pretty progressive and advocate efficiency, etc, but with some things, and this is one of 'em, I defer to nostalgia.

Ya see, railroads get the indication, whatever it might be, from one flashing signal that once took two. Its cheaper and more streamlined, standardized, etc to eliminate all these block signals, these intermediate signals with two signal "heads" and replace them with a new, very reliable color light signal. Searchlight signals still hang on today but they're moving parts make them less attractive than colorlight signals.

Our cheap outfit creates an Approach Diverging by sticking an additional yellow light at the bottom of the head and illuminating both yellows simultaneously...problem is when viewed from more than about a mile away it looks like an Approach, but its actually a much more favorable signal. Starting from the top they have a red, yellow, green, lunar and then the second yellow...thus only two signals, or about 12 inches, maybe, seperate two light bulbs beaming at you in the middle of the night...is it one, or two?

The solution, and the way it used to be, is to put the lunar and the second yellow on a seperate signal head a good distance from the other....6 feet is quite normal...depends on the overall height of the mast. The difference between one foot and 6 is astounding...but, as has been said in other threads, the people that design, decide and buy these signals aren't the ones that have to view them at 2 am.

They've almost dispensed with all of the old signal designs. In the past evey signal had red on top, then yellow, then green...always.
This is where the term, "...the signal dropped on us..", progressed from the old semaphores which would default to a "dropped" position on fail safe mode...ie signal problems, relay/circuit failure, etc.

An important issue to remind everyone of is at one time EOT or Fred's at one point were flashing yellow on some roads...can't remember which ones. I don't think it made wide popularity but can you imagine the effect of unwittingly interchanging a a run-thru train from a railroad who used the flashing yellow FRED's to a road who used flashing yellow signals on their CTC/ABS? I think there were some incidents stemming from the conflict.

J.C. Rausch
Canadian Pacific Railway
Minneapolis, MN, USA, Earth

"all on a flanged wheel."
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Posted by Soo2610 on Saturday, May 26, 2001 7:11 PM
J.C.
Thanks for the sidenote. Sheds a little more light on matters(no pun intended). Also makes a lot of sense. Have never had the privilege of approaching one of these things at 2AM. Only from the interstate overpass.

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Posted by Justicar on Sunday, May 27, 2001 10:00 AM
Len,

No pun taken. :)

I'm curious, after lurking around this forum for several hours yesterday I'm left wondering where the railfan community went after Compuserve died. Certainly no offense to anyone here but I don't recognize any of the names that used to be regulars back on CIS years back. There used to be many, many articulate and knowlegeable posters who knew much more than I did and said it in half the words! lol The forum was also much, much busier than this one. I can't help but think that they're somewhere else. Know of any better forums than this one? My biggest gripe about this one is that its so slow, by design. You have to load a whole new page each time you want to read the next message...even if its only one word. If there are features for tag-lines and ways of looking up members emails I haven't found them yet. There certainly are much more powerful and efficient designs out there.

your mileage may vary...

jcr
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Posted by Soo2610 on Sunday, May 27, 2001 11:26 PM
J.C.
Sorry, but I am relatively new at this and have not done a lot of surfing due to time constraints and the inability to tie up the phone line for too long. My wife is on call 24 hours a day and they invariably try to call as soon as I go on line. Something about Murphy's Law.
I agree with you about this web site being terribly slow. My son is majoring in programming and graphic design in college. He took a look at the programming for this web site when I had problems getting the Rochelle web cam to come in and wasn't terribly complimentary about the programming.
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Posted by Anonymous on Sunday, May 27, 2001 11:56 PM
I agree with you on the inteligence level of some of the posters here. Try Altamont Press RR News at altamontpress.com.
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Posted by Justicar on Monday, May 28, 2001 11:54 AM
As far as finding many of the postings on this forum to be basic general interest stuff I can't say that I'm surprised.
I used to advance the idea back on Compuserve that Trains magazine has been continually dumbing down the information over the years, especially in how they articulate and present it. People were quick to remind me that many, many Trains readers were casual enthusiasts and lacked the background and base knowledge to understand and value a magazine aimed any higher...perhaps.

Should I expect any more from their website? If anything dovetailing the web community in has brought the level lower.
I know very little about airplanes, for example. I suppose if I had some burning question about planes or was writing some paper for a college class I might head over to plains.com and seek help.
That's fine, but I think those things should be left for those who like to handle them, as such there should be a section of the forum designated accordingly leaving the rest of us to talk about how triple valves work, etc.

I'll check out Altamont. Thanks!

73's

jc
CP
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Posted by Anonymous on Monday, May 28, 2001 1:03 PM
It seems that the majority of posters here don't have a real grasp of what railroading is about. I have had experience with many model railroaders that have no concept of what railroading really is. All they see is a train going down the track without rhyme or reason. No understanding of the logistics of moving freight from A to B. There are a few of us professional railroaders here that try to help give them a better understanding.
Altamont Press has a lot of good technical discussions and subjects as well as general railfan info. One other good one is at trainorders.com
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Posted by Justicar on Wednesday, May 30, 2001 2:32 AM
Roger that.

I bopped over to Altamont and ran across many very technical discussions...show's me how little that I know! lol

73's

jc
CP
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Posted by PaulWWoodring on Thursday, May 31, 2001 2:11 PM
Without getting specific about each signal aspect, under CSX and NORAC rules, a flashing light usually upgrades a signal one speed, like from medium to limited speed. This applies to both color position light (ex-B&O) and color light signals.
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Posted by Soo2610 on Thursday, May 31, 2001 11:39 PM
Paul,
Thanks for the reply. Sure never thought when I threw this question out that it would ellicit so many responses.
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Posted by Anonymous on Saturday, June 30, 2001 7:51 PM
The most important thing to remember is that the failure of a device, such as a burned out bulb or a flasher that fails to flash, CANNOT cause a less restrictive aspect to be displayed. For instance a yellow over green whan the yellow burns out would display a clear instead of an approach medium. A light out relay is installed (by law) to transfer the yellow aspect to the bottom unit to give a less restrictive approach aspect.
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Posted by Soo2610 on Saturday, June 30, 2001 10:19 PM
And I thought this was a simple question when I put it out on the forum! All these responses and the effects of a burned out bulb or flasher never came up. I don't think anyone even thought of it until now. I know I didn't.
Thanks, I think.

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