ALL:
My question is regarding the top photo on page 72 of a northbound stack train.
The two headed signal governs southbound movements. What do the two signals indicate? I can’t find their meaning in a UP signal sheet.
Thank you,
Ed Burns
ALL:
My question is regarding the top photo on page 72 of a northbound stack train.
The two headed signal governs southbound movements. What do the two signals indicate? I can’t find their meaning in a UP signal sheet.
Thank you,
Ed Burns
Most commonly signals indicate the occupancy situation behind those signals, and if they are authorized to proceed. While I have not seen the photo, your inquiry suggests there is something mysterious about the signals in question. If so, what is the mysterious you want to know about?
Also, your question in itself is mysterious. Do you want to know about one or two signals?
The signal indicates that the track the northbound train is on is occupied, and therefore is not immediately available for a southbound train.
Eddie, look on the assortment of signals displaying “stop”. The mast has no number plate, so it’s an absolute signal, meaning “stop and stay.”
Although this is the only track I see in the picture (and I’m not familiar with the location), this signal must be at the end of a controlled second track, as it would be incapable of displaying a clear or approach indication.
CShaveRR:
Thanks for the information. I am familiar with the BN-BNSF signal indications. As information, most of the BN signal indications were derived from the GN. I railfaned at Coon Creek, MN (Coon Rapids) growing up. The signals were GN semaphores as Coon Creek was a GN station. A note in the NP St. Paul Division Special Instructions told the crews that “the crossover is exclusive Great Northern track and cannot be used except with permission of the Chief Dispatcher or in an emergency”. I heard that the NP had to pay the GN $25.00 for each crossover move. That is why NP trains used the slow speed crossover in Anoka (next town west of Coon Creek).
Ed Burns
Happily retired NP-BN-BNSF from Minneapolis.
If you look close, there is a second track there to the right. All proceed indications this signal can give (except for a Restricting, if capable) will be of a Diverging nature. That is, red over green, red over flashing yellow, red over yellow. The top single head will always stay red.
Jeff
The location of the photo appears to be here: N 35 17’ 28" W 118 37’ 32".
Note, too, that the signals are of the “Darth Vader” variety. The top signal, having only one lense, will show only a single aspect - red - which follows Jeff’s explanation.
Looking at the satellite view, there is another signal mast which would be out of sight on the right side of the photo.
Southbounds aren’t actually “diverging” there, but adding a second head provides speed control.
Red over green calls for passing through the switch at the prescribed speed (diverging clear).
Red over flashing yellow calls for being able to pass the next signal at not more than 35 MPH (diverging approach medium).
Red over yellow calls for being prepared to stop at the next signal, and at any rate, reducing sp
In SP days (and probably in UP days, until recently) a train leaving Caliente siding would get just-plain-green-- no need for a second head on the signal. How long has this signal been there? UP hasn’t changed Tehachapi to speed signalling, has it?
On the UP it’s called “Diverging Advance Approach” and the associated speed is 40mph.
Signals like that have been replacing old single head signals in similar situations.
Jeff
UP has been replacing signals (actually, I think they’re pretty much done by now) on the line from Mojave to Bakersfield and north on the line paralleling highway 99. The photo shows a northbound train entering the siding at Caliente, so I would expect any southbound signal to be showing red at that CP.
I suspect that, based on what I was seeing in the pass in spring of 2015, that train density late in the afternoon would have been pretty high, as there was a lot of MOW activity in the area with a number of daylight windows closing at about an hour before sunset, followed by a steady parade of trains until about one in the morning.
Just a guess, but I would opine that this train was going to hold in the siding to let a southbound continue uphill.
Coming up from the valley late in the day on a Tuesday in May, 2015, it seemed that every siding was holding a northbound train while a number of southbound trains made their way to Tehachapi. Judging by the number of UP trucks in the motel parking lot that night and the number of MOW folks getting a morning safety and job briefing the next morning, I’m pretty sure that traffic was not moving in the morning and early afternoon.
I pulled those off GCOR, but it just goes to show that even with a common rulebook, things can vary.
That’s why they have Special Instructions in the employee timetable. All sorts of variations from the signals shown in the rulebook will show up there.
The rule book (GCOR) doesn’t show signals in it, even though the various signals have GCOR rule numbers. You have to have the Special Instructions to see the signals.
The first (and maybe the second) edition of GCOR had the signals listed in the book, but later editions left it up to the individual railroads to list the signals in their own special instructions. The first GCOR was the only edition to have rules for movement by train orders.
Jeff
My bad, in a way. Trusted a search for “GCOR signals…”