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Union Pacific Signals...Flashing Yellow

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Posted by Deggesty on Saturday, December 13, 2014 2:53 PM

Actually, there is only one aspect that is not restricting--high green. When I began learning about railroading, I knew only three aspects--green (Proceed), yellow (Approach), and red (Stop). Over the years, I have come to see that there are many different restricting aspects, such as  that for Advance Approach and the difference between a stop signal at an interlocking or a control point (no number plate) and a lineside signal at stop (number plate on the mast or support).

Ordinarily, a flashing light is less restricting than a steady light--but the UP  uses, in interlockings, a red over flashing green, possibly with another red under the flashing green, to indicate diverging clear limited--whereas red over a steady green is diverging clear--if the turnout is good for faster than 40 mph, you may run faster than 40 mph.

Some of the above information comes from an Altamont Press regional TT, which shows the various aspects, their indications, and which road-UP, BNSF, or Amtrak uses a particular aspect. It shows 18 different indications, some of which may have more than one aspect.

With the abolition of position lights, what aspect does Amtrak use to tell an engineer to lower his pantograph?

 

Back when we had dome cars on trains, I always enjoyed sitting in the dome and watching the signals ahead, especially when we were entering an interlocking plant with the many possible different aspects. (Now I have to be content with hearing the wheels going over the switch frogs; it is possible sometimes to stand at the rear when backing into a station.)

Johnny

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Posted by blue streak 1 on Saturday, December 13, 2014 12:12 PM

jeffhergert

 
Jeff>  That is really a comprehensive list of signals that explains most signals.  The only  problem we posters might have are the different aspects under GCOR.
With the problems that have occurred mis understanding on a road not your own maybe these should be USA wide?
The only signal have ever seen different than the above was on CSX that gave a red over yellow over flashing green.  This was into a 7000 foot siding. Did not observe other end of siding.
 
Find it interesting how many displays are restricting. That may be one of the most important displays? 
 
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Posted by K. P. Harrier on Saturday, December 13, 2014 11:59 AM

skippygp123 (12-13):

From your description, the line was found on aerials, and it appears the line, while perhaps using CTC is a low volume line, and the signals do not have a “direction” set by the dispatcher, thus intermediate signals DO NOT have one direction set to red.  Based on your description, the ‘always flashing yellow' signal is the SECOND signal from an interlocking ahead (to the east), which interlocking aerials show is where the line in question crosses another line, at a diamond of some sorts.  Thus, that signal will generally show flashing yellow, UNTIL an eastbound train passes it, the interlocking plant ahead is lined (thus allowing it to be green), a train is occupying the second block ahead (thus the signal in question will display yellow, or a train is approaching in the other direction, in which case the signal will progressively display increasingly more restrictive aspects.  As you said, if you can spend a number of hours by the flashing yellow signal, I think you will eventually see something other than flashing yellow.

Signals look magical, but aren’t,

K.P.

----------------------------------------------------------------------------------------------------------------------------------- K.P.’s absolute “theorem” from early, early childhood that he has seen over and over and over again: Those that CAUSE a problem in the first place will act the most violently if questioned or exposed.

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Posted by skippygp123 on Saturday, December 13, 2014 10:19 AM

Thank you to everyone who replied to my question.  I'm not familiar with railroad vocabulary so I'll do my best to describe the signals in layman's terms.

All of the signals that have been installed are the same.  They have 3 lenses, vertically, and have a black area around a hood which surrounds the lenses.  I am assuming that both (the hood & black material) make it easier to concentrate the light and make the signals easier to see.  Am I correct?

There are signals facing in both directions, each on its own "tower" with a ladder, and are in separate locations, but both are near one another. 

The track in Humbird is a single track, but there is a short siding, just east of the flashing yellow signal and train cars are occasionally left there. 

About 1 1/2 miles east of the flashing signal is a sand plant.  There are several sidings there and cars are picked up and dropped off regularly.  At the sand plant, there are 2 tracks...the one that comes to Humbird and continues west and one that trains occasionally wait on.

Would the "traffic" at the sand plant be the reason that the signal remains in the flashing yellow mode for the trains that are heading in that direction?

There is another signal, facing the east bound trains, that is usually yellow (not flashing) when I head that way.  It is about 3/4 of a mile from the signals in Humbird, but closer to the sand plant.  

There are other signals to the west of Humbird that I've seen either red or green. 

One day, I'm just going to have to sit by the tracks and watch to see what happens. 

This is most interesting!

I do not suffer from insanity...I enjoy every minute of it!!!      Over 60 and still playing with toys!

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Posted by Soo 6604 on Saturday, December 13, 2014 10:09 AM

The Adams line is block controlled. Not CTC (yet). The flashing yellow (flashing yellow/Black) most likely the 2nd signal from a control point (ex: Adams yard, control point: Necedah). The next signal down would be a solid yellow and then the next would be a solid red.

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Posted by BaltACD on Saturday, December 13, 2014 9:15 AM

Paul_D_North_Jr
 
jeffhergert
  
BaltACD

http://signals.jovet.net/rules/UPRR%20Signal%20Rules.pdf

Jeff

 

Mischief Exam on all this Monday morning !

 

- Paul North. 

 

Model board indicates the signal is lined - it is up to personnel in the field to comply with indication that the signal actually displays.  Dispatchers have no knowledge of what indication the signal is actually displaying when the model board indicates it is lined.

Never too old to have a happy childhood!

              

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Posted by Paul_D_North_Jr on Saturday, December 13, 2014 9:05 AM

jeffhergert
  
BaltACD

http://signals.jovet.net/rules/UPRR%20Signal%20Rules.pdf

Jeff

Mischief Exam on all this Monday morning !

- Paul North. 

"This Fascinating Railroad Business" (title of 1943 book by Robert Selph Henry of the AAR)
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Posted by CShaveRR on Friday, December 12, 2014 7:45 PM

I haven't seen any CPLs on the old Alton route for several years.  Not to say that there aren't any left.  

So, Lord Baltimore, your assumption is likely correct.

Jeff, that was supposed to be a secret.  We were supposed to let him think that CSX was changing out those signals!

Carl

Railroader Emeritus (practiced railroading for 46 years--and in 2010 I finally got it right!)

CAACSCOCOM--I don't want to behave improperly, so I just won't behave at all. (SM)

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Posted by BaltACD on Friday, December 12, 2014 5:37 PM

jeffhergert
 
BaltACD 
jeffhergert 
BaltACD
www.railroadsignals.us/rulebooks/up88/UP88aspects.pdf

  

Out of date. This one is more up to date, although I haven't checked to see if everything is still current.

http://signals.jovet.net/rules/UPRR%20Signal%20Rules.pdf

Jeff

 

Interesting that I see B&O signal displays in this.  I suspect that covers the segments of the former Alton that UP is operating????

  

 

Didn't you get the memo on the UP-CSX merger?

Jeff

CSX is taking the former B&O CPL's down as they get ready for PTC.

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Posted by jeffhergert on Friday, December 12, 2014 5:26 PM

BaltACD
 
jeffhergert
 
BaltACD

www.railroadsignals.us/rulebooks/up88/UP88aspects.pdf

 

 

 
 
 

 

 

Out of date. This one is more up to date, although I haven't checked to see if everything is still current.

http://signals.jovet.net/rules/UPRR%20Signal%20Rules.pdf

Jeff

 

 

 

Interesting that I see B&O signal displays in this.  I suspect that covers the segments of the former Alton that UP is operating????

 

Didn't you get the memo on the UP-CSX merger?

Jeff

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Posted by BaltACD on Friday, December 12, 2014 4:59 PM

jeffhergert
 
BaltACD

www.railroadsignals.us/rulebooks/up88/UP88aspects.pdf

 

 

 
 
 

 

 

Out of date. This one is more up to date, although I haven't checked to see if everything is still current.

http://signals.jovet.net/rules/UPRR%20Signal%20Rules.pdf

Jeff

 

Interesting that I see B&O signal displays in this.  I suspect that covers the segments of the former Alton that UP is operating????

Never too old to have a happy childhood!

              

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Posted by jeffhergert on Friday, December 12, 2014 4:52 PM

BaltACD

www.railroadsignals.us/rulebooks/up88/UP88aspects.pdf

 

 

 
 
 

Out of date. This one is more up to date, although I haven't checked to see if everything is still current.

http://signals.jovet.net/rules/UPRR%20Signal%20Rules.pdf

Jeff

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Posted by BaltACD on Friday, December 12, 2014 4:43 PM

Never too old to have a happy childhood!

              

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Posted by K. P. Harrier on Friday, December 12, 2014 4:30 PM

skippygp123 (12-12):

Hi, skippygp123!

When you say the signal in question flashes yellow 24/7, I take it that it does NOT have a red, yellow, or green aspect.  Am I correct?

Is it an intermediate (number plated) or an absolute (un-plated).  Does the mast signal have a counterpart facing the other direction on the same mast, or does it involve a control point (CP, with signals at each end of the CP)?

On the UP Sunset Route here in Southern California, the new two-track intermediate signals are direction orientated, i.e., green (or less) one way and red the other way.  There is a maverick situation on that line in the Thousand Palms area (not to far from the well-known Palm Springs), where from time to time both masts display flashing yellow for both directions, the midpoint between CP’s.

Just above, while to photo shows yellow, both signals are flashing yellow in both directions.  In the distance of that photo, the next mast signals west are seen, but they usually are at least red in one direcrion, and approach lit.

Take care,

K.P.

----------------------------------------------------------------------------------------------------------------------------------- K.P.’s absolute “theorem” from early, early childhood that he has seen over and over and over again: Those that CAUSE a problem in the first place will act the most violently if questioned or exposed.

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Posted by Deggesty on Friday, December 12, 2014 3:16 PM

Flashing yellow is usually telling the engineer to be prepared to stop at the second signal (advance approach).  Is there a crossing with another track down the line? If so, the engineer is being advised that the other track may be in use. If it is not in use, as he approaches it he will be given a less restricting signal, perhaps even a high green, which will give him permission to proceed across the other track at the fastest speed allowed.

A solid yellow tells the engineer to be ready to stop at the next signal (approach), and to reduce his speed so that he will be able to stop at the signal.

Johnny

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Union Pacific Signals...Flashing Yellow
Posted by skippygp123 on Friday, December 12, 2014 1:40 PM

Union Pacific recently installed all new signal "towers" along the line here in Wisconsin.  One east bound signal flashes yellow 24/7.  Other signals change from green to red or vice versa.  Why would this one signal always be a flashing yellow?  What does it mean?

I do not suffer from insanity...I enjoy every minute of it!!!      Over 60 and still playing with toys!

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