CP-SK Changes Its Spots

In 2020 I reported on some unsettling activity at CP-SK on the former Conrail Selkirk branch with new Darth Vader masts going up to replace the Conrail style target signals. CP-SK had been able to avoid the general Selkirk Branch and Chicago Line re-signaling efforts due to a very late 90's re-signaling and the ambient environment of both the former River Line and Boston Line territories holding onto Conrail type signal rules as opposed to Seaboard rules.  In fact the change point was just west of CP-SK at the western limits of the CSX era CP-12.

Well as I feared CP-SK was completely re-signaled and to make matters worse the previous western extent of Seaboard signaling has been moved east to the southern limits of CP-SK on the River Line and the Milepost 9 intermediate signal on the former Selkirk Branch, just east of the Alfred Smith Bridge.

 Although the Milepost 9 intermediate signal has been changed many years prior, it was "future proofed" through the use of Seaboard compatible Y/R/G Approach Slow instead of the NORAC exclusive Y/Y.

The old CP-12 was also made Seaboard ready through the use of R/Y/R Approach Medium (instead of R/*Y*) and extra lamp spaces in which to fit lunar lamps for Seaboard restricting.

In fact the northbound River Line mast at CP-12 seen here displaying a NORAC style R/R/Y Restricting, has that lamp color filter replaced by Lunar White (as visible in this article's first photo). An empty space on the signals lowest head indicates planning for use of Seaboard R/R/Y Slow Approach due to a short signal distance, but it looks like this upgrade was never carried out.

Likely as part of the same re-signaling project, the Conrail style small target searchlight intermediate on the Carman Branch was also undergoing replacement as of August 2022..

In related news CP-153 in Quincy, OH on the former Conrail Indianapolis Line has also seen new CSX signals go up.  The Indy Line has a crazy quilt of new and old signals so this is more of an FYI than a warning of a wide area replacement plan.

Beware the Three Headed Monster

 In North American railroad Signaling truly "universal" rules are pretty rare as in almost every situation one can usually find exceptions.  For having a high green reserved exclusively for Clear is pretty universal except the Bessemer and Lake Erie uses G/*Y* for Approach Limited and G/Y for Limited Clear.  Well another one of these rules is that intermediate signals either have one or two heads. By intermediate signals I am referring to signals with a number plate or signals with offset heads that cannot display an absolute Stop indication. Well there is one big exception to this and it is the Y/R/G Approach Slow indication used by a number of Conrail predecessors like the New York Central and Reading Systems and, more recently, CSX via the Seaboard System. 

 

This results in what I like to call a "three headed monster" in that you have an exceptionally tall intermediate signal that makes one question if they are at an interlocking or not.  Although potentially less of an issue due to PTC, salience is a huge human factors issue and when designing a signaling system from scratch like Caltrain did, making every absolute signal three heads, every automatic distant signals two heads and every basic block signal one head makes it harder for the engineer to become confused about what sort of signal is coming up. The Y/R/G three headed monster sort of blows this approach out of the water, but fortunately Approach Slow is one of the less commonly encountered indications. 

However if one is able to look past the signal policy issues and get into the fun world of rare signaling setups, CSX's three headed monster as a few additional tricks up its sleeve. If an interlocking has both slow and Medium/Limited Speed then you get a 7 lamp, 3 head intermediate signal (GYR-GR-GR) like the ones at Milepost 70 west of Point of Rocks.

 Alright, but I think we can do even better!  What if we had a situation with both Slow and Medium Speed routes AND short signal blocks between that next interlocking and one after.  Well, then we'd have an 8 lamp, 3 head intermediate signal (GYR-GYR-GR) and thanks to some recent capacity expansion and re-signaling work an example now exists in the Richmond area on the Belt Line just west of AY wye.

Don't forget, if CSX had simply adopted the NORAC style signal rules with Y/Y Approach Slow and *Y* Advance Approach they would have been able to do this with 6 lamps and 2 heads, but thanks to their Dixieland myopia we now have what is probably the ultimate intermediate signal. The fact that the masts are on both tracks is even better, 

 
Before I go I would like to mention that there is another three headed intermediate signal still in use and that would be Y/Y/G Approach Diverging on Kansas City Southern. Some newer materials are showing the use of Y/Y and with all the recent re-signaling I am unsure if any Y/Y/G still survives, but it technically could exist. Also, in case anyone was wondering if Canada and its crazy quilt of signal indications has a three headed intermediate, they do not as the indication chart would show it with offset heads and all offset head indications have at most two heads. 

Anyway, if I missed anything or you know other examples of an ultimate intermediate signal location please let me know in the comments.

CSX Talahassee Sub- A New Signaling Museum

CSX's habit of spinning off less profitable subdivisions to short line operators has created another signaling museum, this time in the state of Florida. Similar as to how the Lake State railroad has preserved about 130 miles of C&O era signaling and 1950's vintage code line CTC, the Florida Gulf & Atlantic Railroad has preserved about 250 miles of Seaboard signaling on the former CSX Tallahassee Sub between Baldwin, FL and Tallahassee, FL, where the line becomes DCS controlled. The lease took effect in 2019 and after three years of operation there is so far no indication that the new tenant has any plans to upgrade the signaling.  Not only would it not benefit them financially, but as a Class III operator they are exempt from the PTC requirement. 

The Tallahassee sub signaling museum is important because of CSX's effectiveness in eradicating the seaboard signaling on its S and A lines running between Richmond and Miami/Tampa as well as secondary routes such as the Abbeville Sub.  Despite using Seaboard Style (duh) Color Lights and in some cases 1980's vintage US&S elephant ear signals, CSX was relentless in its modernization efforts.  In the above street view at SE LIVE OAK we can see a US&S TR type target signal with a large type backing that was preferred by the seaboard.  The signal is in a poor man's siding exit bracket with a dwarf adjacent to the mast with a doll arm. All in all the subdivision hosts 29 controlled sidings with 32 interlockings and a large number of intermediate signals between them.  Definitely worth checking out if one happens to be on the I-10 corridor in northern Florida.

Full Up - Signals that Like to Show it All

Signal engineers and signal departments aren't stupid.  If a signal doesn't need to display certain signal aspects then typically those lamps are omitted from the signal.  With vital signaling hardware costing potentially thousands of dollars per lamp, all of that adds up and more often than not the casual viewer is presented with a watered down version of what they might see in the rulebook.  Well today we will find examples across a variety of railroads of signals that don't leave anything behind in the locker room and come equipped to...show it all.

2 x Clear at HOLMES

We'll kick off with an easy one in the form of a PRR/Amtrak position light.  With only two heads it doesn't look like it would be hard to fill up a PRR PL, but both Amtrak and the PRR do make use of an economical lower head that omits the \ position when possible.  Substituting Rule 290 Restricting for Rule 291 Stop and Proceed produces only a minimal decrease in efficiency so the \ is only included in situations where there are regular movements into unsignaled track leaving the SnP dot for movements into an occupied block.

CP-437 in South Bend, IN

NORAC color light signals are typically built around two head masts, but every so often the third head makes an appearance.  This is either when there are slow speed routes or back to back interlockings requiring R/Y/G Medium Approach Medium.

Medium Clear at CARROLL

Of course the more spectacular complete signal is the B&O CPL with a full central target and all six orbitals.  These were especially rare due to the need to have a back to back interlocking with slow speed signals at the next interlocking down to allow for both Approach Slow and Medium Approach Slow.  Due to a similar preference for Stop and Proceed over Restricting, one also tended to  need routes into un-signaled track.  As a result this signal went extinct in the wild twice.  The first being after LAUGHLIN JCT and CURTIS were downgraded and/or resignaled and then again when CARROLL interlocking was first upgraded in 2007, only to be resignaled in 2012.

ALDERSON crossovers.

Sticking with the Chessie system, the C&O's example of a full signal was quite a bit more common than the B&O's.  The use of R/Y/Y for Medium Approach made lower heads rather common.  Add in R/Y/G for Medium Approach Slow (or Medium) and you'll get a complete 3-3-2 configuration as seen above.

CSX SATERWHITE interlocking at the Point of Rocks wye complex.

The Seaboard system makes use of Lunar white for Restricting indications which results in the use of 4-lamp signal heads.  Add slow speed indications into the max and you have 3-4-3 or 3-3-4 lamps combinations on a single mast.

3 by 3 in Salisbury, NC.

 Moving into route signaled systems the Southern Railway most commonly saw 3 x 2 masts with no capacity for Restricting or 3-3-2 when their R/R/Y Restricting indication was required.  While technically speed signaled, every so often a second, possibly slower speed, route at an interlocking would demand use of a fully equipped third head as seen above displaying Diverging (slow) Clear.

The late great HULL interlocking.

The N&W PL system has it even easier than it's PRR cousin to force a full signal.  Without the central market option for a Stop and Proceed, any need to enter an occupied or unsignaled track triggers the need for a lower head \.  Standard use of Diverging Approach covers the / position as well.

Chicagoland commuter system METRA uses a "lunar only" restricting setup similar to CSX, but with route signaling full signals are very rare.  Here is an interesting example at KENSINGTON interlocking on the METRA ELECTRIC.

Southern Pacific's HOWARD Interlocking

 Western roads UP and BNSF both use similar systems that have long used *R* for Restricting allowing 3 by 3 lamp heads to display all necessary indications.  As usual the lowest head is most difficult to populate needing a lower speed route to trigger the R/R/G aspect that provides the only use for G on the lowest head.

However there is one signal that we've left out.  This is the Y/L "Approach Restricting" typically used to signal an upcoming route into a siding on a single track main line.  With no Y/*R* option, Approach Restricting requires a lunar lamp and combined with the need for a second slower speed route one would see a 3-4-3 or 3-3-4 signal, just like on METRA or CSX.  These however are incredibly rare.  So rare that I do not have a photo of one in my collection (although I am sure one exists somewhere).  As UP has a new policy of using Approach Restricting at places with common routes into unsignaled track, UP is the more likely road to have a full signal of this type.  The best I could find was this 9-lampbeast in a 3-4-2 configuration at SWANSTON interlocking near Roseville, CA.

If you have or know of a photo of a UP 10 lamper let me know and I'll update the page :-)

Better Know a Signaling System - Seaboard

Well last time around we explored the signaling system that ate the Northeast.  Now we can explore the signaling system that is eating the signaling system that ate the Northeast. The Seaboard Coast Line railroad, itself an intermodal amalgam of the Atlantic Coast Line and Seaboard Airline, is the 'S' in CSX and the Seaboard system of signals are those which CSX has chosen to standardize on, brushing away the B&O CPLs, C&O color lights and former Conrail NORAC signals.  The reasons is not really due to any inherent superiority, but has more to do with major flaws in both the C&O and B&O systems and the company headquarters being in Jacksonville, FL and NORAC signals were not invented there.  Note I am not going to call these CSX signals because there is still little that CSX has had to do with them, unlike NORAC, which may have borrowed most of the signal rules, but still put its own stamp on them.

Unlike the other dominant signaling system in the South used by the Southern Railway, Seaboard uses speed signals and today is one of the three major codes of speed signaling code along side NORAC and CROR (Canadian signals).  It shares a lot in common with those other codes including the three head (Normal, Medium, Slow) system and Y/G for Approach Medium.  However Seaboard is defined more by its differences than its similarities.

Seaboard's most defining characteristic is its use of Lunar White and only Lunar White for restricting.  There are a few smaller route signaling systems that have this feature, but ever since the availability of *R*, no other major railroad has relied on just Lunar White. 

Back when the Seaboard adopted Lunar for Restricting, Restricting was a seldom used indication, mostly seen where there were routed leading to unsignaled track like yards.  For normal interlockings the Seaboard did not provide any capability to display a "call-on" and therefore they made do with US&S N-3 and 3-color searchlight heads.  However in modern times it is CSX's policy to provide a restricting capability on all controlled signals.  This in turn leads to the frequent use of 4-lamp signal heads, which were nearly unheard of in the area of searchlights and pre-cast color light heads. 

The use of LW for Restricting of course frees up R/Y and R/R/Y for Medium Approach and Slow Approach respectively.  R/Y/R is also used for Medium Approach and is employed by CSX in areas where conversion from non-Seaboard signaling is under way (Conrail, RF&P, P&LE, Etc) or a third signal head is provided.  Lunar white is the first of many instances where CSX management has said "my way or the highway" when its comes to incorporating the signaling ideas of others.  CSX predecessors NORAC, P&LE, RF&P and the C&O all used lower yellow Restricting, which has the advantage of not needing 4-lamp heads, but I guess the south is always right.

 Now just because one had R/Y for Medium Approach doesn't mean that R/*Y* can go unused.  CSX has decided to fill this slot with Limited Approach, which appears to violate the principle of reducing trains to Medium Speed upon passing an Approach indication



Seaboard's other fateful decision was the continued use of Y/Y advance approach, even where the aforementioned alternate speed signal systems had switched over to Y/Y for Approach Slow.  The real kicker is that CSX does not currently use the *Y* aspect, even as an alternate Advance Approach for NORAC compatibility.  This requires that all "patch jobs" require an extra signal head instead of just a flasher relay.  Now if you look closely at the 1989 CSX signal rules I posted above *Y* is listed an a Y/Y alternative, but the original Seaboard set did not include this option and CSX itself later dropped it as well for reasons unknown.

Y/Y Advance Approach on the Abbeville Sub in Bogart, GA where a new interlocking created short blocks.

Without a two lamp Approach Slow indication like Y/Y, all situations involving Slow Speed must use "three headed monsters" to display the Y/R/G flavor.

Like several other pre-NORAC railroads (and the C&O) the Seaboard used R/Y/G for Medium Approach Slow for reasons involving one block sidings that I have already explained.  However CSX chose not to update R/Y/G to the now more common Medium Approach Medium when that indication was added in the 1990s, instead flashing the lower green up "upgrade" the older indication.  If you jump ahead to 6:17 in the following video you can see a CSX medium Approach Medium leading to a R/Y Medium Approach.



In the theoretically sound Caltrain speed signaling system R/Y/Y was chosen as Medium Approach Slow as it worked off the Y/Y/R approach slow and R/Y/G Medium Approach Medium.  Without Y/Y Approach Slow or R/Y/G Medium Approach Medium, Seaboard used R/Y/Y for Medium Advance Approach.  I suspect this might be the rarest signal indication of the Seaboard set as I have yet to positively identify a high signal location where it is employed.

Note: Do not mistake C&O Medium Approach for Seaboard Medium Advance Approach as both use R/Y/Y, but the former is much more common.  C&O signals will be covered later.

Dwarf signals are fairly typical of a speed signaling system with the major exception of Y being Slow Approach instead of Restricting.  The necessity of lunar has made the 4-light Safetrain Unilens dwarf units very popular with CSX.  Here is one displaying the Y/R variety of Slow Approach.

As one might expect R/Y and R/G are Medium Approach and Medium Clear respectively, the latter being perhaps the one case where Seaboard scores a point over NORAC.   One can tell  if a Seaboard dwarf stack protects a medium or slow speed turnout based on the position of the green lamp relative to the red. R/*Y* is provided for Limited Approach, however because of Y/R/G Approach Slow, there is no dwarf version of that indication available. 

 One might expect dwarf Y/Y to be used to the fairly common Advance Approach indication, but, bafflingly is used for Medium Advance Approach.  Unlike using Medium Approach as a Substitute for the missing dwarf Approach indication, a quirk Seaboard shares with NORAC, using Medium Advance Approach would require trains to slow to medium speed first leaving Approach Medium as the short block speed control alternative.

That's pretty much all there is to the Seaboard system of signaling.  It's a solid set of speed signal aspects, but unfortunately was never able to evolve past some of the depricated practices like Y/Y Advance Approach or R/Y/G Medium Approach Slow.  It's a real shame that CSX didn't use the Conrail merger to, at the very least, (re)adopt *Y* as an alternate Advance Approach.  

'C' is for Stop and Check

Some may make fun of the "diversity" of North American signal rules, but they do make for interesting explanations. Today's post brings us to the southern portion of the country for a signal rule unique to the former Seaboard Air Line territory of CSX. The rule in question is 293 which applies to any all red signal with a (C) plate attached to it.

 The rule itself reads.

Stop and check position of drawbridge, spring switch, derail, gates protecting railroad crossing, ensure the way is clear and drawbridge, spring switch, derails, or gates are in proper position and proceed at Restricted speed

The rule sounds simple enough, sort of splitting the difference between a Rule 292 Stop signal and a Rule 291 Stop and Proceed signal. However, to fully understand Stop and Check and the reasons for its use you have to place yourself in the context of the single line, train order based system of operation that predominated in much of North America up until the 1960's. Growing up in the Northeast with its heavily industrialized past it is easy to develop a rather bias view of what railroading should consist of. I.E. Main lines have 2 (or more) tracks, signaled with ABS and interlockings (manned or otherwise) are plentiful, especially at main line diamond crossings and movable bridges. Secondary tracks can be single and controlled by manual block or train orders, but its not such a big deal because those are the old agricultural lines that don't even exist any more. Maybe if a railroad was trying to pinch pennies that might employ something with Absolute Permissive Block with swing switched passing sidings and holdout signals, but that's more an interurban thing. This point of view would also apply in Europe.

Unfortunately this reality only existed where industrial and population conditions allowed for it as things like two track main lines and interlockings are big ticket items that railroads serving areas that consist mostly of empty land or farm fields simply could not afford. In these places the model was single track main lines with passing sidings and some bi-directional ABS if you were lucky. Interlockings were few and far between with diamond crossings and movable bridges getting no special pass on this. Oh, and trains dispatch themselves working with timetable and train order. For a system that did whatever it could to eliminate the need for full fledged interlockings, Rule 293 Stop and Check is to diamond crossings and movable bridges as spring switches and absolute automatic hold out signals are passing sidings.

Stop and Check plated signals are automatics in that there is no human that can push a button and set them to absolute Stop, yet they are attached to things that might often require an absolute stop like diamond crossings and movable bridges. However they can get away with this because what Stop and Check protects does not represent a decision point for the train. Instead of spending money to install an interlocking that must have routes set by a human and must require human intervention in case of a failure, Stop and Check allows train crews to inspect local conditions on their own and continue without external input.

Now the usefulness of Stop and Check is clear in the old Train Order days, but why would they appear on modern CTC lines? Well under early modern CTC schemes where Stop and Check is likely to appear there are several factors at play. First you'll still save money using Stop and Check than installing an interlocking. Second, the majority of railroads outside of the Northeast industrial belt did not adopt a Call-on aspect as standard in their CTC interlockings so if there was a problem affecting the ABS logic of an interlocking a signal could not be displayed even if the routing logic checked out. Passing such signals would require dispatcher intervention, which on a low density line isn't a huge problem, but the more absolute signals one installs, the greater the potential for disruption. Finally, simply fitting an old train order operation main line with CTC doesn't necessarily eliminate the old train order mentality. The line is still single track with short passing sidings. Fitting fully fledged interlockings in the space between these sidings only allows for dispatchers to screw up and create Mexican standoffs at the movable bridge or diamond crossing. Since routing decisions can only be made at passing sidings there is no reason to allow dispatchers to exercise control at intermediate points unless there is an explicit need for a holdout signal.

Alright then, I think this is a pretty good investigation of the context behind Stop and Check so let us look at a real life example located in Athens, Georgia where the CSX Abbeville (nee SAL) crosses the former Central Railroad of Georgia Athens branch crossed. Today the old CoG line is run by a shortline serving local industries north and south of the city. It sees nowhere near the level of traffic as the Abbeville Sub does and therefore there is no need for full time mediation of routes at the crossing. The crossing is also one block north of Fowler Junction passing siding and while a holdout would be appropriate here, it was not seen as necessary.

We begin looking north along the Abbeville Sub and one thing in our immediate favor is that for whatever reason these signals are not approach lit so unlike every other signal on this line we are treated to constant stream of block occupancy and direction of traffic information. Also in evidence is a solar powered rail greaser, and a call box that may or may not still be in operation. Keep in mind this is not an interlocking and as such has no station name associated with it. It's only reference in the employee timetable is on the diagram and there are no special instructions regarding a "railroad crossing at grade. So for train crews the only thing special about this location s that (C) plate.

Nothing too special about the signal except that it is a US&S model N-3 integrated color light with an "elephant ear" type backing. The signal was probably installed along with the CTC project in the 1980's and was at the tail end of the use of the classic N series signals before US&S switched to a new singleton modular unit in the 1990s. In another nod to cost savings the standard maintainer's ladder has been replaced by a set of pole affixed rungs.

The relay box is located by the southbound mast in the southwest quadrant of the crossing. It is of the design typical to ABS signals instead of the bungalow style used for interlockings such as at nearby NE FOWLER JCT. While note the cut telecom line heading into the case which was probably used to report block state back to the dispatcher via a pole line. A similar hook up was similarly cut on the MP 511 automatic. The lack of an ACTS antenna indicates that there is no dispatcher control over anything at this crossing, however the "double wide" relay box indicates that a bit more equipment is present than usually required for a simple ABS boundary.

Looking in the southbound direction we find a much shorter and freshly painted mast protecting the crossing. The northbound signal is much taller due to the presence of a hand operated connecting track to the CoG from the Abbeville Sub in the southwest quadrant ([url]http://acm.jhu.edu/~sthurmovik/Railpics/10-10-10_ATHENS_CROSSING/CSX_Abville-Sub-5055-CoG-connector-sw-gone.html]since removed[/url]) which combined with a curve in the main line could could obstruct the view of a shorter signal.

This mast was freshly painted and was also displaying Stop. Until recently CSX had adopted the common practice of painting the "business" end of its signal masts black and the pole end silver to increase visibility of the signals. With the advent of unpainted aluminum signal structures and Darth Vader hoods this practice only continues with the remaining Conrail territory in New Jersey and Michigan. The (C) plate is made from fiberglass and is similar to the (P) boards that the Seaboard System liked to use to mark its permissive signals with.