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Sunday, December 14, 2025

Caught on Camera - NORAC's Missing Signal Aspect

If you are looking at older versions of the NORAC signal aspect chart you might notice something a bit odd. Most of the common signals indication have a dwarf option for situations with restricted clearance like tunnels or terminal areas. Because of the understandable choice to limit dwarf signals to 1 or 2 elements, some uncommon aspects like R/Y/G Medium Approach Medium are omitted, however until 2018 NORAC also omitted a far more popular signal, Rule 285 "Approach". For those of you who have been living in a cave, Approach, also known as "Caution" in the UK, is "the yellow light" in railroad signaling. A signal so basic that it appears in elementary school books on how trains work. How Rule 285 was neglected in dwarf form is an interesting story of path dependence. 

The story begins with the lamp color yellow performing double duty as for the Restricting indication. When shown alone on a dwarf signal, yellow Restricting, not Approach, so Approach has to be something else. Well, we have two lamps so why not make Approach Y/R? Well dwarf signals are most often used in terminals, terminals are slow so dwarfs really need a Slow Approach indication.  Single lamp *Y* flashing yellow exists and is the preferred option, but back in the day flashing relays were expensive and unreliable so we should probably have a fixed version of Slow Approach. This is where the fateful choice was made. R/Y Slow Approach could have worked. If the Red lamps burns out the signal becomes a Restricting, but the rules boffins likely didn't want R/Y Restricting on a high signal to be confused with R/Y Slow Approach on a dwarf signal because that mistake would likely result in an accident. Therefore dwarf R/Y was given to Restricting, Y/R was given to Slow Approach and Rule 285 Approach was out of luck.

Slow Approach on Track 1 east at CP-97 instead of Approach.

For the sake of correctness NORAC did offer Rule 285 Approach in the form of a PRR pedestal or a B&O dwarf CPL, but these were never options in color light territory or after position light signals began to be phased out. So what was a railroad to do when it needed Rule 285 in a restricted clearance situation? First option was to use Slow Approach, one loses 15mph within interlocking limits, but outside of interlocking limits the rule becomes "regular" approach with a Medium speed limit. The second option was to use Y/*R* Medium Approach, this bumps the speed passing the signal up from Slow to Medium, but ultimately suffers from the same drawback as Slow Approach in that trains can't come at either of these substitutes on a Clear, trains have to hit an Approach Medium or an Approach Slow first. From my field observations Medium Approach was the preferred alternative and could be displayed on either a 2 or 3 lamp modular stack by lighting the yellow lamp and flashing the red below it.



To be fair, the Seaboard system used by CSX also exhibits this problem despite using only using lunar for Restricting with dwarf Y/R for Slow Approach and R/Y for Medium Approach. By forgoing a flashing medium approach CSX lost its latitude for an "easy" dwarf approach aspect. However it was ultimately NORAC that cracked first and in 2018 they adopted *Y*/R as the dwarf option for "straight" Rule 285 Approach. While this now leaves Rule 282a Advance Approach out in the cold, Approach Medium is pretty much a lossless substitute. Of course these sorts of changes can take some time to filter down and it was only recently where I managed to catch one in the wild at SEPTA's WAYNE JCT where a dwarf has replaced a high signal at the end of a platform.



With this change the ball lands back in CSX's court. Will they make some basic changes to its system like adopting *Y* Advance Approach in addition to *Y*/R dwarf Approach?  Or will they keep looking for more "Canadian Combinations".



Sunday, December 7, 2025

Signs! Signs! Everywhere a Sign! - East-West Terminal Railroads

In my previous articles about railroad station signs, I covered passenger and freight railroads in the "east" and "west", but this approach had one small oversight in the form terminal railroads that straddle the east-west divide. These include the Elgin, Joliet and Eastern, Indiana Harbour Belt, , Terminal Railroad Association of St. Louis and Kansas City Terminal. The Minnesota Commercial Railway does not appear to operate any interlockings while the New Orleans Public Belt will see an honorable mention for its now closed interlocking towers. 

Starting off with the IHB, this was a Conrail subsidiary that was later split between NS and CSX. It continues to white on blue Conrail style station signs although in a different font and often mounted on signal gantries or cantilever masts. In a more recent development the interlockings bracketing Gibson Yard, CP-COLUMBIA and CP-GIBSON, have used a Penn Central font with eastbound CP-COLUMBIA in Conrail blue and CP-GIBSON and westbound CP-COLUMBIA in PC black. 


 

 

The EJE, since merged into CN, likely had the most distinctive terminal railroad station signs with green on orange lettering that would typically include the railroad's "The J" logo.  

The BRC, owned jointly by all 6 US Class 1 railways, makes do with a small stencil on the hut or nothing at all. This strategy is shared by the TRRA in St. Louis, although historically a TRRA logo sis appear on some towers.  

The KCT has generally aligned with its local Class 1 KCS using large black lettering on a white background. Historically the wide tower signs had "KC" on either side of the station name. 



This is similar to the New Orleans Public Belt which had similar white on black signs on the two interlocking towers it controlled, EAST BRIDGE JCT and WEST BRIDGE JCT, at either end of the Huey P Long Bridge. 

 


As far as I am aware that's the current state of station signs for the mid-continental terminal railroads as of 2025.

Monday, December 1, 2025

CSX Signal Rules Go Canadian

In September of 2024 CSX added two new signal rules to its rulebooks, Limited Approach Limited and Limited Approach Medium, and examples of both are just starting to appear in the field. In fact I believe this is the first use of a non-cab signal related multiple lamp flashing signal in the United States. If these rules and multi-flash aspects sound both strange and familiar at the same time its because these sort of "combination" signal rules are a standard thing north of the border in Canada


Since the steam era our friends up north have taken the concept of speed signaling to a bit of an extreme with every possible combination of one speed going to another speed given an explicit signal rule. You want to go Slow Speed to Limited and Limited to Slow, Canada has you covered. 


Everywhere else in North America has realized that this extreme amount of signal rules is dumb and will lead to confusion and higher training costs. While some combination indications like Medium Approach Medium or Medium Approach Slow occur frequently enough to be worth including, the remainder are unlikely to see much use and are better off being substituted for (for example downgrading Limited speed combinations to Medium) or covered by special rulebook instructions like NORAC famously allowing trains to diverge over an Approach X type signal indication if the previous signal was not Clear. Anyway it looks like CSX has thrown its lot in with the Canadians and started to care that trains keep that extra bit of Limited Speed when diverging back to back. 


Limited Approach Medium was spotted at on A-Line at SOUTH MICRO where southbound Amtrak Carolinian Train 79 will make an early divergence to its eventual turn off at SELMA with the NORTH SELMA crossovers in between. While the NORTH SELMA crossovers are Medium Speed, T79 would be taking a straight route there so many they just wanted to get it slowed down early for the tight turn onto the H-Line an additional mile beyond. Youtuber Danny Harmon managed to catch a Limited Approach Limited at 10TH ST interlocking on the Vitis Sub. He was also puzzled as to the purpose as the next two signals in the northbound direction were intermediates at standard 2 mile intervals. 


Anyway if you would like my opinion of these new signal rules, necessity aside CSX did a good job picking from those signal aspects that were available to them. Despite CSX's major screw up picking R/Y/G as Medium Approach Slow, which forced Medium Approach Medium to use R/Y/*G*, that mainly presents a problem for a potential Medium Approach Limited. Using R/*Y* for these Limited Approach X signals jives with CSX choice of R/*Y* for Limited Approach. Thus we have Rule 1281-D R/*Y* Limited Approach, 1281-E(?) R/*Y*/G Limited Approach Medium and Rule 1281-F(?) R/*Y*/*G* Limited Approach Limited. (Note I could not determine the actual CSX signal rule numbers at this time so those are my best guesses).

Sunday, November 30, 2025

The Other Rule G

The evolution from "Stop and Proceed" to "Restricted Proceed" in North America is long and something I hope to tackle at a later date. A holdover from the timetable and train order era where waiting for a train running ahead increase its lead made some sense to reduce collisions, the fuel and time savings of allowing following movements to keep moving is hard to deny.  However even where Stop and Proceed are the norm, exceptions are necessary where something like a stiff grade might make restarting a heavy freight train difficult. To implement these exceptions, the (G) or Grade marker was used on automatic signals to relieve some or all trains of the need to stop when paired with a Stop and Proceed indication.


Stop and Proceed was especially popular in the Northeast United States, but after Conrail was picked apart by NS and CSX, most of the major northeastern freight territory fell under the spell of Restricted Proceed.  At this point the G marker appeared to be on its way out as the remaining NORAC roads were either passenger focused or too small to have signals or heavy freight trains. However, as the limited speed triangle, Amtrak's Harrisburg line turned into an unwitting refuge. The PRR's Main Line between Philadelphia and Harrisburg was surprisingly hilly and saw more than its fair share of automatic signals with (G) markers applied.

One might assume that the spread of Rule 562 cab signals without intermediate wayside signals and complete lack of through freight would put the Main Line's (G) markers into a terminal decline, however at the Milepost 21 intermediate signal, a minor capacity project may have what could be the last new main line (G) marker to be installed in the United States. 

When Amtrak wanted to upgrade the single direction tracks tracks between the SEPTA Yard at Frazer and the start of 4-track operation at Paoli, they modified Milepost 21 intermediate signal location for bi-directional operation on both tracks with new Safetran colorized position lights and (G) markers in the eastbound direction.  Moreover, the (G) even uses the same old school blocky font as opposed to the smoother letter used on things like (D)istant and (A)pproach markers.

It's anyone's guess how much longer these (G) markers will be around for as the track segment they govern will soon be subjected to the Rule 562 treatment. Another part of Amtrak territory south of Wilmington also features both long freight trains and (G) markers, but it too going the 562 route so its a good chance that these will be the last new (G)'s installed in the United States. 




Sunday, November 23, 2025

Small Changes at Western Ave

While out visiting METRA TOWER A-2 at Chicago's Western Ave for the first time in many years, I noticed that the US&S H-2 dwarf searchlight signals at the adjacent TOWER A-3 interlocking had been replaced by L&W LED searchlights with a small backing target. It is unclear if this took place in conjunction with the 2019 removal of legacy PRR position lights at TOWER A-2. TOWER A-3 is remote from a panel inside the staffed TOWER A-2 and the interlocking's other distinctive features including gantry mounted main line searchlights and A-5 pneumatic point machines had been left untouched. You can see the difference between the old H-2 searchlights and newer LED dwarfs below.

  


An interesting feature is that the 6L dwarf appears to illuminate only with a route is lines (or I assume upon the occupation of adjacent track circuits). This signal is placed after a train exits the main line, but before it is routed to a yard track. I managed to catch the 6L LED dwarf displaying a flashing red "Restricted Proceed" indication for a yard move, in conjunction with a lunar white Restricting aspect on the 10L gantry signal. (Note the 10L signal displays "3rd head Restricting" with a phantom center head.)



I assume that the H-2 yard dwarfs always displayed R stop or L Restricting and the LED units changed this to *R* Restricted Proceed as is the style today. I guess its cheaper to have an LED unit with just a single color of LED's, but I will point out that Union Pacific did choose to use lunar LED searchlights at the nearby KEDZIE interlocking.


Saturday, November 15, 2025

Tight Jeans: Position Lights As The PRR Intended

We all know the PRR Position Light signal looks like this with the round upper head and the (usually) squared off lower head. Both backing targets are technically interchangeable with each other (Although I have never seen a lower head type target used on an upper head.). 

However what would you think if I told you that this concept of the PRR PL did not reflect the original vision of the author. A while ago I wrote up a post discussing the compact position light and how the lamp arms of a US&S pattern position light can support a PL lamp module at any point along their length.  At the time I thought that there were two standard PL setups, full size and compact. Well it turns out there is a third method of lamp arrangement which was actually the standard setup used by the PRR in its final few decades. 

While the PRR was an industrial behemoth that didn't hesitate to spend on quality, there were a few areas where its famed standardization turned more towards penny pinching. One of these was the configuration for the lower heads of its position light signals. To make the signals stand out in bright sun, a dark backing target would be necessary. However there would be little need for this contrast if an approaching train was moving at slow speed below 30mph. Therefore the PRR only applied a backing to the lower | position as the lower / and \ positions would be approached at something more like 15mph. 

If you look closely at one of these original pattern lower heads you'll also see that the modules for the / and \ positions are not positioned at the ends of the mounting arms. Instead they are scrunched in couple inches. Although not to the level seen in compact PL arrangements, this scrunch may have been to provide some contrast without the "expense" of a backing plate. 

See the difference between the placement of the lamps on the | vs the \ position.

I am sure the rivet counting modelers are yelling at their screens right now about my obliviousness, but somehow I had never noticed this before. I guess this is partly because unmodified PRR position lights have become so uncommon, but also because later lower backing plate thoroughly set the expectation that the spacing would be the same on both heads. Anyway now I know and now you know as well.




Friday, November 7, 2025

Hoboken Terminal's Suspended Signals

Stations with large terminal fans often exhibit a problem at one or both of edge tracks. Because rail vehicles can't generally make hard right turns, one needs a longer series of switches to reach the highest and/or lowest track. Unfortunately terminals often abut a fixed location like a river or street or public square and to avoid having those extreme tracks things can get a little squished. In the early 1980s, New Jersey Transit engaged in a near total reconstruction of the former Delaware, Lackawanna and Western electrified suburban network. Not only was the 3kv DC traction power system under powered and on its last legs, but the signaling system was firmly rooted in the 1920's. In the re-signaling project that followed, NJT built the last great North American interlocking tower, TERMINAL TOWER and replaced most vestiges of the former DL&W plant.

New (frame left) and old HOBOKEN TERMINAL TOWERs shortly before cutover.

In the late DL&W era Hoboken Terminal signals consisted largely of two head, small target searchlight signals displaying the DL&W's unique mix of color light signal indications. Long platforms in the center of the terminal had these mounted on signal gantries in the normal way, while tracks towards the edge of the low 1908 train shed saw signals mounted below the gantries under the shed itself. Moreover, while center tracks could get a "straight" clear out of town, tracks towards the edges had to make do with a Restricting indication as the DL&W lacked Slow Clear and Slow Approach options, even on dwarfs. 

When NJT rebuilt the signaling there appears to be a time when the new signals were wired into the old HOBOKEN TERMINAL tower's old US&S 1908 Electro-Pneumatic interlocking machine. To make the cutover process easier, signal locations were largely kept the same, but NJT had no desire to keep the old handicap of trains of edge tracks departing under a Restricting signal indication. This meant that the replacement "high" signals had to display R/R/G Slow Clear as opposed to the G and G/G on a dwarf. In most locations this wasn't a big deal as the signal gantries could easily support three tri-light heads, however on tracks 2, 3, 12 and 13, the need to suspend signals under the trainshed due to the closeness of the first switches presented a bit of a problem.

TERMINAL TOWER 36W2 and 36W1 suspended signals governing tracks 3 and 2 respectively.

TERMINAL TOWER 88W and 92W suspended signals governing tracks 13 and 12 respectively.

The solution was somewhat akin to a Penn Station signal, just with three "heads" instead of two. To display R/R/G, R/R/*Y* and R/R/Y, two fixed Safetran modular dwarf cubes were mounted close above an additional three-unit cluster of modular dwarf cubes. These were then mounted close under the roof at the westernmost end of the trainshed.

36W2 signal governing track #3.

 

Although a bit inelegant compared to a dwarf or today's compact LED searchlights, they are a unique solution in today's largely homogeneous signaling environment and are likely to persist for many years to come.